阅读说明：本技术 一种测量船用燃油舱内液面位置的传感器及其工作方法 (Sensor for measuring liquid level position in marine fuel tank and working method thereof ) 是由 唐猛 姜南 于 2021-08-20 设计创作，主要内容包括：本发明涉及舰船燃油舱监控技术领域,公开了一种测量船用燃油舱内液面位置的传感器及其工作方法,即所述传感器包括有安装机构、保护筒、长方形隔板、第一电容测量探针、第二电容测量探针和处理模块,所述第二电容测量探针被绝缘层包裹且使所述第二电容测量探针的底端位置低于所述第一电容测量探针的底端位置,从而可以在传感器安装后基于常规的电容检测和液位高度测量原理,根据标定数据的拟合函数和通过长短不一的两电容测量探针所采集获取的两电容测量值,确定与所述两电容测量值对应的燃油液面位置和油水界面位置,实现对舱底浸水监测并同时测量燃油液位的目的,进而可提高船舶运行的安全性和抗损管能力,特别适用于应用在无人船领域中。(The invention relates to the technical field of ship fuel tank monitoring, and discloses a sensor for measuring the liquid level position in a ship fuel tank and a working method thereof, namely the sensor comprises an installation mechanism, a protection barrel, a rectangular partition plate, a first capacitance measuring probe, a second capacitance measuring probe and a processing module, wherein the second capacitance measuring probe is wrapped by an insulating layer, and the bottom end position of the second capacitance measuring probe is lower than that of the first capacitance measuring probe, so that the fuel liquid level position and the oil-water interface position corresponding to two capacitance measuring values are determined according to a fitting function of calibration data and the two capacitance measuring values acquired by the two capacitance measuring probes with different lengths after the sensor is installed based on the conventional capacitance detection and liquid level height measuring principle, and the purposes of monitoring the immersion water at the bottom of the tank and simultaneously measuring the fuel liquid level are realized, and further, the safety and the anti-damage pipe capacity of the ship operation can be improved, and the ship is particularly suitable for being applied to the field of unmanned ships.)

1. The sensor for measuring the liquid level position in the marine fuel tank is characterized by comprising an installation mechanism (1), a protection cylinder (2), a rectangular partition plate (3), a first capacitance measuring probe (41), a second capacitance measuring probe (42) and a signal acquisition and calculation processing module (5), wherein the installation mechanism (1) is used for installing the whole sensor on the top of the tank body or the side wall of the tank body of the marine fuel tank (100);

the top end of the protection cylinder (2) is fixedly connected with the mounting mechanism (1), and the protection cylinder (2) is positioned in the space in the marine fuel tank (100) after the sensor is mounted;

the rectangular partition plate (3) is positioned in the protection barrel (2) and is parallel to the center line of the barrel body of the protection barrel (2), the width of the rectangular partition plate (3) is consistent with the inner diameter of the protection barrel (2), and the length of the rectangular partition plate (3) is consistent with the length of the protection barrel (2), so that the internal space of the protection barrel (2) is divided into a first measurement space (21) and a second measurement space (22);

the first capacitance measuring probe (41) is positioned in the first measuring space (21) and is parallel to the rectangular partition plate (3) at intervals, the top end of the first capacitance measuring probe (41) is fixedly connected with the mounting mechanism (1), and the first capacitance measuring probe (41) and the cylinder wall of the protection cylinder (2) are arranged at intervals;

the second capacitance measuring probe (42) is positioned in the second measuring space (22) and is parallel to the rectangular partition plate (3) at intervals, the top end of the second capacitance measuring probe (42) is fixedly connected with the mounting mechanism (1), the second capacitance measuring probe (42) is wrapped by an insulating layer and is arranged at intervals with the cylinder wall of the protection cylinder (2), and the bottom end position of the second capacitance measuring probe (42) is lower than that of the first capacitance measuring probe (41);

the signal acquisition and calculation processing module (5) is fixed on the mounting mechanism (1) and two input ends of the signal acquisition and calculation processing module are respectively and electrically connected with the output end of the first capacitance measuring probe and the output end of the second capacitance measuring probe (42).

2. A sensor according to claim 1, wherein said rectangular partition (3) and said first capacitance measuring probe (41) are made of metal respectively, and the bottom end position of said first capacitance measuring probe (41) is slightly lower than or level with the fuel outlet position after the sensor is mounted.

3. The sensor according to claim 1, wherein the mounting mechanism (1) comprises an insertion cylinder (11), a flange (12), a cylindrical boss and a probe fixing ring, wherein the insertion cylinder (11) is used for being inserted into a mounting through hole on the top of the cabin body or the side wall of the cabin body during mounting, the flange (12) is coaxially connected with the outboard end part of the insertion cylinder (11) and is used for being butted and fixed with the outboard flange of the mounting through hole during mounting, and the cylindrical boss is coaxially arranged on the inboard end surface of the insertion cylinder (11);

the diameter of the cylindrical boss is matched with the inner diameter of the protection cylinder (2), and the top end of the protection cylinder (2) is in inserted fit with the cylindrical boss to realize fixed connection with the mounting mechanism (1);

the cylindrical boss is provided with a step hole, the probe fixing ring is fixedly installed in the step hole, the top end of the first capacitance measuring probe (41) and the top end of the second capacitance measuring probe (42) are fixed in the probe fixing ring through fixing joints respectively, and the fixing connection with the installation mechanism (1) is realized.

4. The sensor according to claim 1, characterized in that the bottom of the protective cylinder (2) is fitted with a fixed ring (23), inside which ring of the fixed ring (23) an insulating spacer is radially fitted, wherein the insulating spacer is used to position the bottom of the oblong diaphragm (3) and the bottom of the second capacitance measuring probe (42).

5. The sensor according to claim 1, characterized in that the bottom end position of the protective cylinder (2) is lower than the fuel outlet position of the marine fuel tank (100) after the sensor is installed, and the elevation difference between the bottom end position of the protective cylinder (2) and/or the bottom end position of the second capacitance measuring probe (42) and the lowest position in the marine fuel tank (100) after the sensor is installed is between 5mm and 15 mm.

6. The sensor according to claim 1, characterized in that the cylinder walls of the first measuring space (21) and the second measuring space (22) are provided with a plurality of liquid through holes (24) which are sequentially arranged at intervals from top to bottom.

7. The sensor according to claim 1, wherein a plurality of insulating support frames (25) are respectively arranged on two side plate surfaces of the rectangular partition plate (3) at intervals from top to bottom, wherein the insulating support frames (25) are used for fixing and supporting the first capacitance measuring probe (41) or the second capacitance measuring probe (42) on the corresponding side.

8. The sensor according to claim 1, wherein the signal acquisition and computation processing module (5) comprises a signal acquisition circuit board (51), a computation processing circuit board, and a display (53) and a data transmission connector (54) which are located outside the cabin after the sensor is installed, wherein two input ends of the signal acquisition circuit board (51) are respectively and electrically connected with an output end of the first capacitance measurement probe and an output end of the second capacitance measurement probe (42), an output end of the signal acquisition circuit board (51) is in communication connection with an input end of the computation processing circuit board, and two output ends of the computation processing circuit board are respectively and communicatively connected with the display (53) and the data transmission connector (54).

9. A working method of the sensor according to any one of claims 1 to 8, characterized in that the sensor is installed and then executed by a signal acquisition and calculation processing module (5), and the working method comprises a data calibration stage and a liquid level measurement stage;

the data calibration stage comprises the following steps:

when pure oil is contained in the cabin space of the marine fuel oil cabin (100), aiming at each cabin calibration liquid level in a plurality of cabin calibration liquid levels, acquiring a corresponding first capacitance calibration value through a first capacitance measurement probe (41), and acquiring a corresponding second capacitance calibration value through a second capacitance measurement probe (42);

according to the one-to-one correspondence relationship between the plurality of cabin interior calibration liquid levels and the plurality of first capacitor calibration values, fitting to obtain a first fitting function, and according to the one-to-one correspondence relationship between the plurality of cabin interior calibration liquid levels and the plurality of second capacitor calibration values, fitting to obtain a second fitting function;

saving the first fitting function and the second fitting function;

the liquid level measuring stage comprises:

acquiring a first capacitance measurement value through a first capacitance measurement probe (41), and acquiring a second capacitance measurement value through a second capacitance measurement probe (42);

determining a first intra-tank measurement liquid level corresponding to the first capacitance measurement value according to the first fitting function, and determining a second intra-tank measurement liquid level corresponding to the second capacitance measurement value according to the second fitting function;

judging whether the absolute value of the liquid level difference between the measured liquid level in the first cabin and the measured liquid level in the second cabin is smaller than a preset threshold value or not;

if the average value of the measured liquid level in the first cabin and the measured liquid level in the second cabin is smaller than the average value of the measured liquid level in the first cabin and the measured liquid level in the second cabin, the position of an oil-water interface is determined to be below the bottom end position of the second capacitance measuring probe (42), otherwise, the measured liquid level in the first cabin is determined to be the position of the fuel level, and the position of the oil-water interface is determined to be between the bottom end position of the first capacitance measuring probe (41) and the bottom end position of the second capacitance measuring probe (42).

10. The operating method according to claim 9, wherein when the rectangular partition (3) and the first capacitance measuring probe (41) are made of metal respectively, and the bottom end position of the first capacitance measuring probe (41) is slightly lower than or kept at the fuel outlet position after the sensor is installed, the operating method further comprises:

in the liquid level measuring stage, after a first capacitance measuring value is acquired through a first capacitance measuring probe (41), if the first capacitance measuring value is judged to exceed a capacitance calibration value range, the oil-water interface position is judged to be the bottom end position of the first capacitance measuring probe (41), and an alarm signal is sent out, wherein the capacitance calibration value range is determined by the maximum value and the minimum value of a plurality of first capacitance calibration values.

Technical Field

The invention belongs to the technical field of monitoring of fuel tanks of ships, relates to application, measurement and safety guarantee of fuel oil of ships and innovative products integrating the application, measurement and safety guarantee of the fuel oil of ships, and particularly relates to a sensor for measuring the liquid level position in a fuel tank of a ship and a working method of the sensor.

Background

At present, the measurement of fuel in a fuel tank of a ship is mainly focused on the measurement of the liquid level position of the fuel, and the remaining amount of the fuel can be calculated through the measured liquid level height data and a tank capacity table of the tank, which is the main mode and purpose (the measurement purpose is to determine the amount of the remaining fuel) of the fuel tank applied to the domestic ship for monitoring and measuring. However, in the practical application process, monitoring of the fuel tank is performed, and besides monitoring of the fuel liquid level, monitoring of other applications also exists, such as monitoring of accumulated water at the bottom of the fuel tank. At present, in the application process of a plurality of ships, the monitoring of the accumulated water at the bottom is manually carried out, namely, the oil-water interface position at the bottom of the cabin is manually observed (an observation window needs to be arranged at the bottom of the cabin), or the monitoring is realized by a manual identification method such as discharging the liquid at the bottom of the cabin at regular intervals. At present, no effective and feasible technical scheme for achieving the aim based on an automatic sensing monitoring means exists.

In general ship application, due to a certain water content in fuel oil, water in a cabin is gradually condensed for a long time. Because the condensation takes a certain time, and the total amount is not large, the harm of the water to the fuel application can be eliminated through regular manual detection or observation. However, when the cabin enters the fuel tank for other reasons (such as damage in wartime, damage in collision, damage in pipelines of other devices or artificial error operation, etc.), because the seawater is heavier than the fuel, the seawater is gathered at the bottom of the cabin, and the fuel oil in the fuel oil cabin provides energy for the whole power system, the oil outlet position of the power plant is close to the bilge position (generally, the oil outlet position is slightly higher than the lowest position of the bilge, the purpose of the operation is to prevent water, impurities and the like at the bilge from being input into the power plant together, but generally, the height is not too high from the bilge position, otherwise, a plurality of fuel oil can not be used), or the sea water may enter the fuel delivery pipe due to the shaking of the ship, thereby bringing about great safety risk and hidden trouble. Particularly, in the unmanned ship market, along with the gradual development, growth and maturity of unmanned technologies and industries, the unmanned ship has the characteristics of long outgoing time, unattended operation, difficulty in complete control of a running track, relatively small volume and the like, so that the unmanned ship cannot be found and solved in time by people when problems occur, the monitoring of the unmanned ship related to the safety process becomes more and more important, a fuel oil system is an important link and is a key point of monitoring, and once the fuel oil is soaked (or soaked and accumulated to a certain degree), the whole fuel oil engine is fatal to the whole fuel oil engine.

In view of the more and more urgent marine ocean navigation requirements and the rapid development of the unmanned ship industry, the fuel oil use and condition monitoring of ships become more and more important, and therefore, a novel sensor is needed to achieve the purpose of monitoring bilge immersion and simultaneously measuring the fuel oil level so as to improve the safety and the anti-damage capability of the ship operation.

Disclosure of Invention

The invention aims to solve the problem that the existing ship fuel tank monitoring technology cannot automatically monitor bilge immersion and simultaneously measure the fuel liquid level, and provides a novel sensor for measuring the liquid level position in a ship fuel tank and a working method thereof, which can realize the purposes of monitoring bilge immersion and simultaneously measuring the fuel liquid level, further improve the safety and damage-resistant management capability of ship operation and are particularly suitable for being applied to the field of unmanned ships.

In a first aspect, the technical scheme adopted by the invention is as follows:

a sensor for measuring the liquid level position in a marine fuel tank comprises an installation mechanism, a protection barrel, a rectangular partition plate, a first capacitance measuring probe, a second capacitance measuring probe and a signal acquisition and calculation processing module, wherein the installation mechanism is used for installing the whole sensor on the top of a tank body or the side wall of the tank body of the marine fuel tank;

the top end of the protection cylinder is fixedly connected with the mounting mechanism, and the protection cylinder is positioned in the cabin space of the marine fuel cabin after the sensor is mounted;

the rectangular partition plate is positioned in the protection cylinder and is parallel to the center line of the cylinder body of the protection cylinder, the width of the rectangular partition plate is consistent with the inner diameter of the protection cylinder, and the length of the rectangular partition plate is consistent with that of the protection cylinder, so that the internal space of the protection cylinder is divided into a first measurement space and a second measurement space;

the first capacitance measuring probe is positioned in the first measuring space and is parallel to the rectangular partition plate at intervals, the top end of the first capacitance measuring probe is fixedly connected with the mounting mechanism, and the first capacitance measuring probe and the cylinder wall of the protection cylinder are arranged at intervals;

the second capacitance measuring probe is positioned in the second measuring space and is parallel to the rectangular partition plate at intervals, the top end of the second capacitance measuring probe is fixedly connected with the mounting mechanism, the second capacitance measuring probe is wrapped by the insulating layer and is arranged at intervals with the cylinder wall of the protection cylinder, and the bottom end position of the second capacitance measuring probe is lower than that of the first capacitance measuring probe;

the signal acquisition and calculation processing module is fixed on the mounting mechanism, and two input ends of the signal acquisition and calculation processing module are respectively and electrically connected with the output end of the first capacitance measuring probe and the output end of the second capacitance measuring probe.

Based on the content of the invention, the invention provides a novel sensor for measuring the liquid level position in a fuel tank for a ship, which comprises an installation mechanism, a protection cylinder, a rectangular partition plate, a first capacitance measuring probe, a second capacitance measuring probe and a signal acquisition and calculation processing module, wherein the second capacitance measuring probe is wrapped by an insulating layer, and the bottom end position of the second capacitance measuring probe is lower than that of the first capacitance measuring probe, so that the fuel liquid level position and the oil-water interface position corresponding to the two capacitance measuring values can be determined according to a fitting function of calibration data and the two capacitance measuring values acquired by the two capacitance measuring probes with different lengths after the sensor is installed based on the conventional capacitance detection and liquid level height measuring principle, the purposes of monitoring immersion water at the bottom of the tank and simultaneously measuring the fuel liquid level are realized, and the safety and the pipe damage resistance of the ship in operation can be further improved, is particularly suitable for being applied to the field of unmanned ships.

Preferably, the rectangular partition plate and the first capacitance measuring probe are respectively made of metal materials, and the bottom end position of the first capacitance measuring probe is slightly lower than or level with the fuel outlet position after the sensor is installed.

Preferably, the mounting mechanism comprises an inserting cylinder, a flange, a cylindrical boss and a probe fixing ring, wherein the inserting cylinder is used for being inserted into a mounting through hole on the top of the cabin body or the side wall of the cabin body during mounting, the flange is coaxially connected with the outboard end part of the inserting cylinder and is used for being butted and fixed with the outboard flange of the mounting through hole during mounting, and the cylindrical boss is coaxially arranged on the inboard end face of the inserting cylinder;

the diameter of the cylindrical boss is matched with the inner diameter of the protection cylinder, and the top end of the protection cylinder is in inserted fit with the cylindrical boss to realize fixed connection with the mounting mechanism;

the cylindrical boss is provided with a step hole, the probe fixing ring is fixedly installed in the step hole, the top end of the first capacitance measuring probe and the top end of the second capacitance measuring probe are fixed in the probe fixing ring through fixing connectors respectively, and the fixing connection with the installation mechanism is achieved.

Optimized, solid fixed ring is installed to the bottom of a protection section of thick bamboo gu fixed ring's intra-annular is radially installed insulating locating rack, wherein, insulating locating rack is used for the location the bottom of rectangle baffle with the bottom of second capacitance measurement probe.

Preferably, the bottom end position of the protection cylinder is lower than the fuel oil outlet position of the marine fuel oil cabin after the sensor is installed, and the elevation difference between the bottom end position of the protection cylinder and/or the bottom end position of the second capacitance measurement probe and the lowest position in the marine fuel oil cabin after the sensor is installed is between 5 and 15 mm.

Preferably, a plurality of liquid through holes are formed in the cylinder walls of the first measuring space and the second measuring space, and the liquid through holes are sequentially arranged from top to bottom at intervals.

Optimized, be provided with a plurality of from last to the insulating support frame of interval arrangement in proper order down on the both sides face of rectangle baffle respectively, wherein, insulating support frame is used for fixed and support corresponding side first capacitance measurement probe or second capacitance measurement probe.

Preferably, the signal acquisition and computation processing module comprises a signal acquisition circuit board, a computation processing circuit board, and a display and a data transmission connector which are located outside the cabin after the sensor is installed, wherein two input ends of the signal acquisition circuit board are respectively and electrically connected with an output end of the first capacitance measurement probe and an output end of the second capacitance measurement probe, an output end of the signal acquisition circuit board is in communication connection with an input end of the computation processing circuit board, and two output ends of the computation processing circuit board are respectively and communicatively connected with the display and the data transmission connector.

In a second aspect, the invention adopts the technical scheme that:

a working method of the sensor according to the first aspect is executed by a signal acquisition and calculation processing module after the sensor is installed, and comprises a data calibration stage and a liquid level measurement stage;

the data calibration stage comprises the following steps:

when pure oil is contained in the cabin space of the marine fuel oil cabin, aiming at each cabin calibration liquid level in the multiple cabin calibration liquid levels, acquiring a corresponding first capacitance calibration value through a first capacitance measurement probe, and acquiring a corresponding second capacitance calibration value through a second capacitance measurement probe;

according to the one-to-one correspondence relationship between the plurality of cabin interior calibration liquid levels and the plurality of first capacitor calibration values, fitting to obtain a first fitting function, and according to the one-to-one correspondence relationship between the plurality of cabin interior calibration liquid levels and the plurality of second capacitor calibration values, fitting to obtain a second fitting function;

saving the first fitting function and the second fitting function;

the liquid level measuring stage comprises:

acquiring a first capacitance measurement value through a first capacitance measurement probe, and acquiring a second capacitance measurement value through a second capacitance measurement probe;

determining a first intra-tank measurement liquid level corresponding to the first capacitance measurement value according to the first fitting function, and determining a second intra-tank measurement liquid level corresponding to the second capacitance measurement value according to the second fitting function;

judging whether the absolute value of the liquid level difference between the measured liquid level in the first cabin and the measured liquid level in the second cabin is smaller than a preset threshold value or not;

and if the average value of the measured liquid level in the first cabin and the measured liquid level in the second cabin is smaller than the average value of the measured liquid level in the first cabin and the measured liquid level in the second cabin, the oil-water interface position is determined to be below the bottom end position of the second capacitance measuring probe, otherwise, the measured liquid level in the first cabin is determined to be the fuel liquid level position, and the oil-water interface position is determined to be between the bottom end position of the first capacitance measuring probe and the bottom end position of the second capacitance measuring probe.

Preferably, when the rectangular partition plate and the first capacitance measuring probe are made of metal materials respectively, and the bottom end position of the first capacitance measuring probe is slightly lower than the fuel outlet position or is kept level with the fuel outlet position after the sensor is installed, the working method further comprises the following steps:

in the liquid level measuring stage, after a first capacitance measuring value is acquired through a first capacitance measuring probe, if the first capacitance measuring value is judged to exceed a capacitance calibration value range, the oil-water interface position is judged to be the bottom end position of the first capacitance measuring probe, and an alarm signal is sent out, wherein the capacitance calibration value range is determined by the maximum value and the minimum value of a plurality of first capacitance calibration values.

The invention has the beneficial effects that:

(1) the invention provides a novel sensor for measuring the liquid level position in a fuel tank for a ship, which comprises an installation mechanism, a protection cylinder, a rectangular partition plate, a first capacitance measuring probe, a second capacitance measuring probe and a signal acquisition and calculation processing module, wherein the second capacitance measuring probe is wrapped by an insulating layer, and the bottom end position of the second capacitance measuring probe is lower than that of the first capacitance measuring probe, so that the fuel liquid level position and the oil-water interface position corresponding to the two capacitance measuring values can be determined according to a fitting function of calibration data and the two capacitance measuring values acquired by the two capacitance measuring probes with different lengths after the sensor is installed on the basis of the conventional capacitance detection and liquid level height measuring principle, the purposes of monitoring the immersion water at the tank bottom and simultaneously measuring the fuel liquid level are realized, and the safety and the anti-damage pipe capability of the ship in operation can be further improved, is particularly suitable for being applied to the field of unmanned ships;

(2) the fuel oil liquid level position and the oil-water interface position can be accurately positioned through a special algorithm, so that the residual oil quantity and the bilge immersion condition can be accurately monitored, and the safety and the damage-resistant pipe capability of ship operation are further improved;

(3) through the material design of the partition plate and the short probe and the design of the mounting position of the bottom end of the short probe, whether the oil-water interface is close to or rises to the fuel outlet position can be automatically recognized, so that an alarm can be timely triggered to remind of closing the fuel outlet, automatically closing the fuel outlet or starting a water body discharge task, and finally the operation safety of a ship power system is guaranteed;

(4) the sensor also has the advantages of high installation stability, reliable measuring result, capability of splicing and prolonging the measuring range, simple structure and the like, and is convenient for practical application and popularization.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a main body of a sensor provided by the present invention.

Fig. 2 is a schematic circuit diagram of the sensor according to the present invention.

Fig. 3 is an exemplary illustration of a mounting mechanism for mounting a sensor on a fuel tank of a ship provided by the present invention.

FIG. 4 is an exemplary graph of a plurality of intra-tank calibration levels versus a plurality of first capacitance calibration values as provided by the present invention.

FIG. 5 is an exemplary graph of a plurality of intra-tank calibration levels and a plurality of second capacitance calibration values fitted to the curves provided by the present invention.

FIG. 6 is an exemplary plot of a plurality of calibrated levels of the tank versus a plurality of third calibrated values of the capacitor between two bottom positions of the probe according to the present invention.

In the above drawings: 1-an installation mechanism; 11-penetrating the column; 12-a flange plate; 2-a protective cylinder; 21-a first measurement volume; 22-a second measurement volume; 23-a fixed ring; 24-liquid through hole; 25-an insulating support frame; 3-a rectangular partition board; 41-a first capacitance measurement probe; 42-a second capacitance measurement probe; 5-a signal acquisition and calculation processing module; 50-header; 51-a signal acquisition circuit board; 53-display; 54-data transmission joint; 100-fuel oil tank for ship; 101-fuel level; 102-oil-water interface; 103-lowest position in the cabin; 200-fuel outlet.

Detailed Description

The invention is further described with reference to the following figures and specific embodiments. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. Specific structural and functional details disclosed herein are merely representative of exemplary embodiments of the invention. This invention may, however, be embodied in many alternate forms and should not be construed as limited to the embodiments set forth herein.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of exemplary embodiments of the present invention.

It should be understood that, for the term "and/or" as may appear herein, it is merely an associative relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, B exists alone, and A and B exist at the same time; for the term "/and" as may appear herein, which describes another associative object relationship, it means that two relationships may exist, e.g., a/and B, may mean: a exists independently, and A and B exist independently; in addition, for the character "/" that may appear herein, it generally means that the former and latter associated objects are in an "or" relationship.

Example one

As shown in fig. 1 to 3, the sensor for measuring the liquid level position in the marine fuel tank provided in this embodiment includes an installation mechanism 1, a protective cylinder 2, a rectangular partition plate 3, a first capacitance measurement probe 41, a second capacitance measurement probe 42, and a signal acquisition and calculation processing module 5, where the installation mechanism 1 is used to install the entire sensor on the top of the marine fuel tank 100 or on the sidewall of the marine fuel tank; the top end of the protection cylinder 2 is fixedly connected with the mounting mechanism 1, and the protection cylinder 2 is positioned in the cabin space of the marine fuel oil cabin 100 after the sensor is mounted; the rectangular partition plate 3 is positioned inside the protection cylinder 2 and is parallel to the center line of the cylinder body of the protection cylinder 2, the width of the rectangular partition plate 3 is consistent with the inner diameter of the protection cylinder 2, and the length of the rectangular partition plate 3 is consistent with the length of the protection cylinder 2, so that the internal space of the protection cylinder 2 is divided into a first measurement space 21 and a second measurement space 22; the first capacitance measuring probe 41 is positioned in the first measuring space 21 and is parallel to the rectangular partition plate 3 at intervals, the top end of the first capacitance measuring probe 41 is fixedly connected with the mounting mechanism 1, and the first capacitance measuring probe 41 and the cylinder wall of the protection cylinder 2 are arranged at intervals; the second capacitance measuring probe 42 is positioned in the second measuring space 22 and is parallel to the rectangular partition plate 3 at an interval, the top end of the second capacitance measuring probe 42 is fixedly connected with the mounting mechanism 1, the second capacitance measuring probe 42 is wrapped by an insulating layer and is arranged at an interval with the cylinder wall of the protection cylinder 2, and the bottom end position of the second capacitance measuring probe 42 is lower than the bottom end position of the first capacitance measuring probe 41; the signal acquisition and calculation processing module 5 is fixed on the mounting mechanism 1, and two input ends of the signal acquisition and calculation processing module are respectively and electrically connected with the output end of the first capacitance measuring probe and the output end of the second capacitance measuring probe 42.

As shown in fig. 1 and 3, in the specific structure of the sensor, the specific structure of the mounting mechanism 1 can be selectively determined according to the mounting space provided by the marine fuel tank 100, if the top of the cabin body of the marine fuel tank 100 has the mounting space, the mounting mechanism 1 can structurally adopt a top-mounted flange mounting mechanism matched with the mounting space so as to insert the whole sensor from a cabin top mounting through hole and realize the fixed mounting of the sensor through flange butting, otherwise, the mounting mechanism 1 can structurally adopt a side-mounted flange mounting mechanism so as to insert the whole sensor from a side wall mounting through hole and realize the fixed mounting of the sensor through flange butting. Of course, the mounting mechanism 1 can also be embodied in other specific structures, such as a suction cup fixing structure. In addition, if the sensor is long (i.e. the protective barrel 2 is long), a fixed support frame (not shown in the drawing) can be further installed at a position, close to the bottom of the sensor, of the inner side wall of the cabin (i.e. the bottom of the protective barrel 2), so as to provide a restraining effect for the bottom of the sensor after installation and prevent the bottom of the sensor from shaking all around.

The protective cylinder 2 is used for protecting the two probes inside and is used as a ground wire reference for capacitance measurement; the posture of the protection cylinder 2 after installation is preferably in a vertical state, so that the one-to-one correspondence relationship between the calibrated liquid level in the cabin and the calibrated value of the capacitor can be accurately obtained, and the determination precision of the final liquid level position is ensured. The rectangular partition plate 3 is used for dividing the space in the protection cylinder 2 into two independent vertical measurement spaces: the first measurement space 21 and the second measurement space 22, so as to house corresponding capacitance measurement probes, respectively; the first measuring space 21 and the second measuring space 22 are preferably semi-cylindrical spaces divided in half. In addition, the bottom port of the protective cylinder 2 is an open port, so that the liquid level inside and outside the cylinder (including the fuel level and the oil-water interface) is always kept consistent, and the determination precision of the final liquid level position is ensured.

The first capacitance measurement probe 41 and the second capacitance measurement probe 42 are respectively used for acquiring and acquiring capacitance measurement signals corresponding to the liquid level in the tank based on the existing capacitance measurement principle, so that the signal acquisition and calculation processing module 5 converts the capacitance measurement signals into capacitance measurement values after inputting the capacitance measurement signals. The first capacitance measuring probe 41 is mainly used for collecting capacitance measuring signals when the surroundings are in a pure oil state, and the first capacitance measuring probe 41 can be exposed without an insulating layer because fuel oil has good insulating property. The second capacitance measurement probe 42 is mainly used for acquiring capacitance measurement signals when the periphery is in a pure oil state or when an oil-water interface position is between bottom end positions of the two probes, and the second capacitance measurement probe 42 needs to be wrapped by an insulating layer due to conductivity of water, wherein the insulating layer is preferably a sealed tetrafluoride tube which can be sleeved outside the second capacitance measurement probe 42 so as to insulate the second capacitance measurement probe 42. When the top end position of the first capacitance measuring probe 41 is kept level with the top end position of the protection cylinder 2, the length of the first capacitance measuring probe 41 needs to be shorter than the length of the protection cylinder 2; when the position of the top end of the first capacitance measuring probe 41 is kept level with the position of the top end of the second capacitance measuring probe 42, the length of the second capacitance measuring probe 42 needs to be longer than the length of the first capacitance measuring probe 41; meanwhile, when the tip position of the protection cylinder 2 is kept flat with the tip position of the second capacitance measuring probe 42, the length of the second capacitance measuring probe 42 may be slightly longer (for example, 5mm long) or slightly shorter (for example, 5mm short) than the length of the protection cylinder 2. In addition, the first capacitance measuring probe 41 and the second capacitance measuring probe 42 are preferably unipolar probes.

The signal acquisition and calculation processing module 5 is used as a signal processing core of the whole sensor, and is used for realizing the following working principle based on the conventional capacitance detection and liquid level height measurement principle: after the sensor is installed, firstly, calibration data including a plurality of voltage calibration values corresponding to a plurality of cabin calibration liquid levels (including fuel liquid level positions, pure water liquid level positions and/or oil-water interface positions and the like) in a one-to-one manner are acquired through the first capacitance measurement probe 41 and the second capacitance measurement probe 42, a fitting function is determined based on the one-to-one correspondence relationship between the plurality of cabin calibration liquid levels and the plurality of voltage calibration values in the calibration data, then two capacitance measurement values are acquired through the first capacitance measurement probe 41 and the second capacitance measurement probe 42 during liquid level measurement, and finally the fuel liquid level positions and the oil-water interface positions of the marine fuel tank 100 corresponding to the two capacitance measurement values are determined through the fitting function, so that the purposes of monitoring the immersion of the tank bottom and simultaneously measuring the fuel liquid level are achieved. The signal acquisition and computation processing module 5 can be implemented by, but not limited to, a microprocessor chip of the model STM32F103 series and its peripheral circuits.

Therefore, through the detailed description of the structure and the working principle of the sensor, the novel sensor for measuring the liquid level position in the fuel tank for the ship is provided, namely the novel sensor comprises an installation mechanism, a protection barrel, a rectangular partition plate, a first capacitance measuring probe, a second capacitance measuring probe and a signal acquisition and calculation processing module, wherein the second capacitance measuring probe is wrapped by an insulating layer, and the bottom end position of the second capacitance measuring probe is lower than that of the first capacitance measuring probe, so that the fuel liquid level position and the oil-water interface position corresponding to the two capacitance measuring values are determined according to a fitting function of calibration data and the two capacitance measuring values acquired by the two capacitance measuring probes with different lengths based on the conventional capacitance detection and liquid level height measuring principle after the sensor is installed, and the purposes of monitoring immersion water at the bottom of the tank and simultaneously measuring the fuel liquid level are realized, and further, the safety and the anti-damage pipe capacity of the ship operation can be improved, and the ship is particularly suitable for being applied to the field of unmanned ships.

Optimally, in order to realize accurate positioning of the fuel liquid level position and the oil-water interface position, the working method of the sensor is executed by the signal acquisition and calculation processing module 5 after the sensor is installed, and the working method comprises but is not limited to a data calibration stage and a liquid level measurement stage.

The data calibration phase includes, but is not limited to, the following steps: when the cabin space of the marine fuel oil cabin 100 contains pure oil (referring to anhydrous fuel oil), aiming at each cabin calibration liquid level in a plurality of cabin calibration liquid levels, acquiring a corresponding first capacitance calibration value through a first capacitance measurement probe 41, and acquiring a corresponding second capacitance calibration value through a second capacitance measurement probe 42; according to the one-to-one correspondence relationship between the plurality of cabin interior calibration liquid levels and the plurality of first capacitor calibration values, fitting to obtain a first fitting function, and according to the one-to-one correspondence relationship between the plurality of cabin interior calibration liquid levels and the plurality of second capacitor calibration values, fitting to obtain a second fitting function; saving the first fitting function and the second fitting function. The calibrated liquid levels in the plurality of chambers can be liquid level range scales above the fuel outlet 200, for example, scales every 50mm on the range of 0-1400 mm; the acquisition process and the fitting process of the capacitance calibration value can be realized based on the prior art, and the obtained fitting curve graphs of the first fitting function and the second fitting function are respectively shown in fig. 4 and 5 and are in approximate linear relation.

The liquid level measuring stage includes, but is not limited to, the following steps: acquiring a first capacitance measurement value through a first capacitance measurement probe 41, and acquiring a second capacitance measurement value through a second capacitance measurement probe 42; determining a first intra-tank measurement liquid level corresponding to the first capacitance measurement value according to the first fitting function, and determining a second intra-tank measurement liquid level corresponding to the second capacitance measurement value according to the second fitting function; judging whether the absolute value of the liquid level difference between the measured liquid level in the first cabin and the measured liquid level in the second cabin is smaller than a preset threshold value or not; if the average value of the measured liquid level in the first cabin and the measured liquid level in the second cabin is smaller than the average value of the measured liquid level in the first cabin and the measured liquid level in the second cabin, the average value of the measured liquid level in the first cabin and the measured liquid level in the second cabin is used as the fuel liquid level position of the marine fuel tank 100, and the oil-water interface position is judged to be located below the bottom end position of the second capacitance measuring probe 42, otherwise, the measured liquid level in the first cabin is used as the fuel liquid level position, and the oil-water interface position is judged to be located between the bottom end position of the first capacitance measuring probe 41 and the bottom end position of the second capacitance measuring probe 42.

Because the capacitance measurement value is closely related to the relative dielectric constant of the medium between the probe and the cylinder wall, and the relative dielectric constant of water is far greater than that of fuel oil, when the oil-water interface position is between the bottom end position of the first capacitance measurement probe 41 and the bottom end position of the second capacitance measurement probe 42, the difference between the second measured liquid level in the second cabin determined according to the second fitting function and corresponding to the second capacitance measurement value and the first measured liquid level in the first cabin determined according to the first fitting function and corresponding to the first capacitance measurement value is extremely large, as long as the absolute value of the liquid level difference exceeds the preset threshold value, the bottom end position of the second capacitance measurement probe 42 can be judged to have been immersed in water, and the liquid level position of the fuel oil can be accurately determined.

Further optimized, the oil-water interface position can be accurately positioned according to the following working method:

the data calibration phase further includes, but is not limited to, the following steps: when pure water (referring to a water body without fuel) is contained in the cabin space of the marine fuel oil cabin 100, aiming at each of a plurality of cabin calibration liquid levels between the bottom ends of the two probes, a corresponding third capacitance calibration value is acquired through the acquisition of the second capacitance measurement probe 42; fitting to obtain a third fitting function according to the one-to-one correspondence relationship between the plurality of calibration liquid levels in the cabin between the bottom end positions of the two probes and the plurality of third capacitance calibration values; saving the third fitting function;

the liquid level measuring stage further includes, but is not limited to, the following steps: when it is determined that the oil-water interface position is located between the bottom end position of the first capacitance measurement probe 41 and the bottom end position of the second capacitance measurement probe 42, the oil-water interface position H is derived as follows_WO：

H_1,O＝f_1,O(C₁)＝f′_1,O(C₁)·C₁

f_2,W(C₂)＝f′_2,W(C₂)·C₂

In the formula, C₁Representing said first capacitance measurement, f_1,O(C₁) The representative variable is the first fitted function, f 'of the first capacitance measurement'_1,O(C₁) Representing the derivative of said first fitted function, C₂Representing said second capacitance measurement, f_2,O(C₂) Said second fitted function, f ', representative variable being said second capacitance measurement'_2,O(C₂) Representing the derivative of said second fitted function, f_2,W(C₂) Said third fitted function, f ', representative variable being said second capacitance measurement'_2,W(C₂) Representing the derivative of said third fitted function, H_1,ORepresenting the measured level of liquid in said first chamber.

The fitting curve of the third fitting function can be exemplified as shown in fig. 6, and also has an approximately linear relationship. Meanwhile, because the bottom end of the second capacitance measuring probe 42 is immersed in water, the measured second capacitance value is affected by the water under the oil-water interface and the fuel oil on the oil-water interface, which can be regarded as the parallel effect of the first equivalent capacitance corresponding to the water under the oil-water interface and the second equivalent capacitance corresponding to the fuel oil on the oil-water interface, and therefore, the formula is providedFurther, the oil-water interface position H can be derived_WOThe precise calculation formula of (2).

Preferably, the rectangular partition plate 3 and the first capacitance measuring probe 41 are made of metal materials, and the bottom end position of the first capacitance measuring probe 41 is slightly lower (for example, lower than 5mm) than or even with the fuel outlet position after the sensor is installed. Therefore, when the oil-water interface 102 rises to the bottom end position of the first capacitance measuring probe 41, the first capacitance measuring probe 41 is in short circuit with the rectangular partition plate 3 due to the electric conduction of the water body, and at the moment, the capacitance measured value acquired by the first capacitance measuring probe 41 jumps particularly, so that the signal acquisition and calculation processing module 5 identifies that the oil-water interface is close to or rises to the fuel outlet position according to the jump, and then sends out an alarm to remind of closing the fuel outlet, automatically closing the fuel outlet or starting a water body discharge task, and finally the operation safety of the ship power system is ensured. That is, further optimized, the working method further includes but is not limited to the following: in the liquid level measurement stage, after a first capacitance measurement value is acquired through a first capacitance measurement probe 41, if the first capacitance measurement value is judged to exceed a capacitance calibration value range, the oil-water interface position is judged to be the bottom end position of the first capacitance measurement probe 41, and an alarm signal is sent out, wherein the capacitance calibration value range is determined by the maximum value and the minimum value of a plurality of first capacitance calibration values. Further, the first capacitance measuring probe 41 may be made of, but is not limited to, material 316L.

Preferably, the mounting mechanism 1 includes a penetrating cylinder 11, a flange 12, a cylindrical boss and a probe fixing ring, wherein the penetrating cylinder 11 is used for being inserted into a mounting through hole located at the top of the cabin body or on the side wall of the cabin body during mounting, the flange 12 is coaxially connected to the outboard end of the penetrating cylinder 11 and is used for being butted and fixed with the outboard flange of the mounting through hole during mounting, and the cylindrical boss is coaxially arranged on the inboard end face of the penetrating cylinder 11; the diameter of the cylindrical boss is matched with the inner diameter of the protection cylinder 2, and the top end of the protection cylinder 2 is in inserted fit with the cylindrical boss to realize fixed connection with the mounting mechanism 1; the cylindrical boss is provided with a step hole, the probe fixing ring is fixedly installed in the step hole, the top end of the first capacitance measuring probe 41 and the top end of the second capacitance measuring probe 42 are fixed in the probe fixing ring through fixing joints respectively, and the fixing connection with the installation mechanism 1 is realized. As shown in fig. 1 and 3, by the specific design of the installation mechanism 1, the purpose of installing the whole sensor on the top or the side wall of the fuel tank 100 for a ship can be achieved, and the installation stability of the protection cylinder 2 and the two capacitance measurement probes can be ensured. Further optimally, in order to ensure the stability of the inserting fit, after the top end of the protection barrel 2 is inserted and matched with the cylindrical boss, the protection barrel 2 and the cylindrical boss are fixed through a welding structure or a lateral bolt structure (namely, corresponding threaded holes are formed in the side wall of the protection barrel 2 and the side surface of the cylindrical boss, and screws are screwed into the threaded holes to achieve the purpose of bolt fixing). And in order to facilitate the installation of the entire sensor from outside the cabin, the outer diameter of the protective cylinder 2 is smaller than the diameter of the penetrating cylinder 11. In addition, when the mounting mechanism 1 adopts a side-mounted flange mounting mechanism, the penetrating column 11 needs to be bent by 90 degrees so as to ensure that the posture of the protection cylinder 2 is still vertical after mounting.

Optimally, the bottom of the protection cylinder 2 is provided with a fixing ring 23, and an insulating positioning frame is radially arranged in the ring of the fixing ring 23, wherein the insulating positioning frame is used for positioning the bottom of the rectangular partition plate 3 and the bottom of the second capacitance measuring probe 42. Through the design of the fixing ring 23 and the insulating positioning frame, the bottom of the rectangular partition plate 3 and the bottom of the second capacitance measuring probe 42 can be positioned and stabilized, and the reliability of the acquisition of capacitance measured values is ensured. In addition, the insulating positioning frame can be made of, but is not limited to, polytetrafluoroethylene.

Preferably, the bottom end position of the protection cylinder 2 is lower than the fuel outlet position of the marine fuel tank 100 after the sensor is installed, and the elevation difference between the bottom end position of the protection cylinder 2 and/or the bottom end position of the second capacitance measuring probe 42 and the lowest position in the marine fuel tank 100 after the sensor is installed is between 5 and 15 mm. By the installation design described above, it is ensured that the range of the sensor can be extended as far as possible to the bottom of the fuel tank 100 for a ship, as shown in fig. 3, with an elevation difference of 10mm for example. In addition, although the length of the protection cylinder 2 can be designed according to the measurement range requirement, in general, for transportation and ship cabin installation requirements, the longest length of the protection cylinder 2 is limited within 2 meters, and if the measurement range is larger than the protection cylinder length, the measurement range can be expanded by splicing in a mode that a plurality of groups of sensors are installed from top to bottom in sequence.

Preferably, a plurality of liquid through holes 24 are formed in the cylinder walls of the first measuring space 21 and the second measuring space 22, and the liquid through holes are sequentially arranged from top to bottom at intervals. As shown in fig. 1 and 3, the liquid fluidity inside and outside the cylinder can be improved by the vertical design of the liquid through hole 24, so that the liquid level inside and outside the cylinder (including the fuel level and the oil-water interface) is kept consistent all the time, and the determination precision of the final liquid level position is ensured. Further, as shown in fig. 1 and 3, the liquid passage hole 24 may be a long hole, for example.

Optimized, be provided with a plurality of from last to the insulating support frame 25 of interval arrangement in proper order down on the both sides face of rectangle baffle 3 respectively, wherein, insulating support frame 25 is used for fixing and supports corresponding side first capacitance measurement probe 41 or second capacitance measurement probe 42. As shown in fig. 1, since the capacitance measuring probe needs to measure the whole measuring range length, and if the capacitance measuring probe is too long, the capacitance measuring probe will bend and deform, so that the insulating support frame 25 can ensure the capacitance measuring probe to be fastened and not to deform, and ensure the electrical conduction between the probe and the partition plate to be not conducted and not to contact the cylinder wall. In addition, the insulating support 25 may be made of, but not limited to, teflon.

Preferably, the signal collecting and calculating module 5 includes a signal collecting circuit board 51, a calculating circuit board, and a display 53 and a data transmission connector 54 which are located outside the cabin after the sensor is installed, wherein two input ends of the signal collecting circuit board 51 are respectively and electrically connected to an output end of the first capacitance measuring probe and an output end of the second capacitance measuring probe 42, an output end of the signal collecting circuit board 51 is in communication connection with an input end of the calculating circuit board, and two output ends of the calculating circuit board are respectively and communicatively connected to the display 53 and the data transmission connector 54. As shown in fig. 1 and 2, the signal acquisition circuit board 51 is disposed in the mounting mechanism 1, and the computation processing circuit board, the display 53 and the data transmission connector 54 can be disposed on a header 50 (which is necessarily located outside the cabin) fixedly connected to the flange 12, wherein the signal acquisition circuit board 51 is configured to acquire capacitance measurement signals by cooperating with two capacitance measurement probes based on a capacitance measurement principle, and send the capacitance measurement signals to the computation processing circuit board, which can be implemented by using an existing signal acquisition circuit; the calculation processing circuit board is used for realizing the following working principle based on the liquid level height measurement principle: after the sensor is installed, firstly, a fitting function is determined based on the one-to-one correspondence relationship between a plurality of intra-cabin calibration liquid levels and a plurality of voltage calibration values in calibration data, then, when the liquid level is measured, the fuel liquid level position and the oil-water interface position of the marine fuel oil cabin 100, which correspond to two capacitance measurement values, are determined through the fitting function, so that the purposes of monitoring the immersion of the cabin bottom and measuring the fuel liquid level are realized, and the method can be realized by adopting a microprocessor chip of an STM32F103 series and a peripheral circuit thereof; the display 53 is used for displaying measurement data or working state, and may be but not limited to a liquid crystal display screen; the data transmission connector 54 is used for outputting measurement data or an alarm signal, and may adopt, but is not limited to, an RS485 bus interface so as to output the measurement data or the alarm signal to an upper computer based on a Modbus protocol.

In summary, the sensor for measuring the liquid level position in the marine fuel tank and the working method thereof provided by the embodiment have the following technical effects:

(1) the embodiment provides a novel sensor for measuring the liquid level position in a marine fuel tank, which comprises an installation mechanism, a protection barrel, a rectangular partition plate, a first capacitance measuring probe, a second capacitance measuring probe and a signal acquisition and calculation processing module, wherein the second capacitance measuring probe is wrapped by an insulating layer, and the bottom end position of the second capacitance measuring probe is lower than that of the first capacitance measuring probe, so that the fuel liquid level position and the oil-water interface position corresponding to two capacitance measuring values can be determined according to a fitting function of calibration data and the two capacitance measuring values acquired by the two capacitance measuring probes with different lengths based on the conventional capacitance detection and liquid level height measuring principle after the sensor is installed, the purposes of monitoring the immersion water at the tank bottom and simultaneously measuring the fuel liquid level are realized, and the safety and the anti-damage pipe capability of the ship operation can be improved, is particularly suitable for being applied to the field of unmanned ships;

(2) the fuel oil liquid level position and the oil-water interface position can be accurately positioned through a special algorithm, so that the residual oil quantity and the bilge immersion condition can be accurately monitored, and the safety and the damage-resistant pipe capability of ship operation are further improved;

(3) through the material design of the partition plate and the short probe and the design of the mounting position of the bottom end of the short probe, whether the oil-water interface is close to or rises to the fuel outlet position can be automatically recognized, so that an alarm can be timely triggered to remind of closing the fuel outlet, automatically closing the fuel outlet or starting a water body discharge task, and finally the operation safety of a ship power system is guaranteed;

(4) the sensor also has the advantages of high installation stability, reliable measuring result, capability of splicing and prolonging the measuring range, simple structure and the like, and is convenient for practical application and popularization.

Finally, it should be noted that the present invention is not limited to the above alternative embodiments, and that various other forms of products can be obtained by anyone in light of the present invention. The above detailed description should not be taken as limiting the scope of the invention, which is defined in the claims, and which the description is intended to be interpreted accordingly.