Function testing device and calibration method for exhaust gas recirculation system of internal combustion engine

文档序号：1902019 发布日期：2021-11-30 浏览：20次中文

阅读说明：本技术 一种内燃机废气再循环系统功能测试装置及标定方法 (Function testing device and calibration method for exhaust gas recirculation system of internal combustion engine ) 是由赵从龙徐俊艾志辉于 2021-07-27 设计创作，主要内容包括：本发明涉及内燃气测试技术领域,具体涉及一种内燃机废气再循环系统功能测试装置及标定方法。包括废气模拟装置、进气脉冲阀、转换接头、测示单元、空气流量计、第一压力/温度传感器和EGR阀开度控制器,所述测试单元包括依次连接的EGR阀、EGR冷却器、EGR管路和压差底座,所述废气模拟装置依次通过进气脉冲阀和转换接头连接至EGR阀,所述第一压力/温度传感器设置于进气脉冲阀与转换接头之间,空气流量计设置于转换接头与EGR阀之间,第一压力/温度传感器的信号输出端与废气模拟装置的反馈信号输入端电性连接,所述EGR阀开度控制器的控制信号输出端与EGR阀的控制信号输入端电性连接。本装置能在没有发动机和发动机台架的情况下实现EGR阀功能测试。(The invention relates to the technical field of internal combustion gas testing, in particular to a function testing device and a calibration method for an internal combustion engine exhaust gas recirculation system. Including exhaust gas simulation device, the pulse valve that admits air, crossover sub, survey and show unit, air flow meter, first pressure temperature sensor and EGR valve opening controller, the test unit is including EGR valve, EGR cooler, EGR pipeline and the pressure differential base that connects gradually, exhaust gas simulation device loops through the pulse valve that admits air and crossover sub and is connected to the EGR valve, first pressure temperature sensor sets up between pulse valve and crossover sub, and air flow meter sets up between crossover sub and EGR valve, and first pressure temperature sensor's signal output part and exhaust gas simulation device's feedback signal input electric connection, EGR valve opening controller's control signal output part and EGR valve control signal input electric connection. The device can realize the function test of the EGR valve under the condition without an engine and an engine pedestal.)

1. A functional test device for an exhaust gas recirculation system of an internal combustion engine is characterized in that: including exhaust gas simulation device, air intake pulse valve, crossover sub, survey and show unit, air flow meter, first pressure temperature sensor and EGR valve opening controller, the test unit is including EGR valve, EGR cooler, EGR pipeline and the pressure differential base that connects gradually, exhaust gas simulation device loops through air intake pulse valve and crossover sub and is connected to the EGR valve, first pressure temperature sensor sets up between air intake pulse valve and crossover sub, air flow meter sets up between crossover sub and EGR valve, first pressure temperature sensor's signal output part and exhaust gas simulation device's feedback signal input electric connection, EGR valve opening controller's control signal output part and EGR valve control signal input electric connection.

2. The functional test device of an exhaust gas recirculation system of an internal combustion engine according to claim 1, characterized in that: the waste gas simulation device comprises a pressure control cabinet and a temperature control cabinet, wherein the pressure control cabinet is used for controlling the waste gas pressure before the air inlet pulse valve, and the temperature control cabinet is used for controlling the waste gas temperature before the air inlet pulse valve.

3. The functional test device of an exhaust gas recirculation system of an internal combustion engine according to claim 1, characterized in that: the EGR valve further comprises a second pressure/temperature sensor and a third pressure/temperature sensor, wherein the second pressure/temperature sensor and the third pressure/temperature sensor are respectively arranged at the air inlet end and the air outlet end of the EGR valve.

4. The functional test device of an exhaust gas recirculation system of an internal combustion engine according to claim 1, characterized in that: the EGR cooler is characterized by further comprising a temperature sensor and a differential pressure sensor, wherein the temperature sensor is arranged on an EGR pipeline behind the EGR cooler, a first interface of the differential pressure sensor is connected with an air inlet end of the differential pressure base, and a second interface of the differential pressure sensor is connected with an air outlet end of the differential pressure base.

5. The functional test device of an exhaust gas recirculation system of an internal combustion engine according to claim 1, characterized in that: the testing device is characterized by further comprising a fresh air simulation device, a mixer and a pressure control cabinet, wherein the air outlet end of the fresh air simulation device and the air outlet end of the testing unit are both connected to the air inlet end of the mixer, the air outlet end of the mixer is connected with the air inlet end of the pressure control cabinet, and the air outlet end of the pressure control cabinet is communicated with the atmosphere.

6. The functional test device of an exhaust gas recirculation system of an internal combustion engine according to claim 1, characterized in that: the air inlet pulse valve adopts a butterfly valve structure and is used for outputting airflow in a pulse mode.

7. The functional test device of an exhaust gas recirculation system of an internal combustion engine according to claim 1, characterized in that: and the air outlet end of the adapter is connected with an air inlet pipeline of the EGR valve through a V-shaped hoop.

8. A method of calibrating an apparatus as recited in claim 1, wherein said method of calibrating is an EGR flow correction factor calibration method, said method comprising:

the EGR valve opening controller controls the EGR valve to open to a specified opening;

acquiring air flow meter data, differential pressure sensor data, engine intake pressure data and EGR cooled exhaust gas temperature data under the current opening degree;

calculating EGR flow data by utilizing an EGR flow calculation formula based on the acquired differential pressure sensor data, the engine intake pressure data, the EGR cooled exhaust gas temperature data, the differential pressure base inlet area data and the differential pressure base outlet area data;

and calibrating an EGR flow correction coefficient under the current opening degree by taking the EGR flow data equal to the air flow meter data under the current opening degree as a target.

9. The calibration method according to claim 8, further comprising:

the EGR valve opening controller controls the EGR valve to be opened to different opening positions between 0 and 100 in sequence;

acquiring EGR flow correction coefficients of the EGR valve under different opening degrees;

and obtaining an EGR flow correction coefficient calibration table based on EGR flow correction coefficients of different opening degrees of the EGR valve.

Technical Field

The invention relates to the technical field of internal combustion gas testing, in particular to a function testing device and a calibration method for an internal combustion engine exhaust gas recirculation system.

Background

The exhaust gas recirculation system generally includes an EGR valve, an EGR cooler, an EGR differential pressure signal assembly, and an EGR gas connection line. At present, model selection, calibration and problem search of the exhaust gas recirculation system are based on an engine bench test, bench resources and engine complete machine resources need to be prepared in advance, and the model selection and calibration work of the exhaust gas recirculation system can be carried out only after the engine complete machine is built, so that a large amount of time is wasted.

Therefore, there is a great need for a device that performs a functional test of the EGR valve without the engine and engine mount.

Disclosure of Invention

The invention aims to provide a function testing device and a calibration method of a gas turbine exhaust gas recirculation system, aiming at the defects of the prior art, and not only can the flow capacity test of an EGR valve, the temperature and pressure drop test of the EGR valve and the calibration of an EGR flow correction coefficient be realized without building an engine bench, but also a great deal of time is saved for project development.

The invention provides a function testing device of an exhaust gas recirculation system of an internal combustion engine, which comprises an exhaust gas simulation device, an air inlet pulse valve, a conversion joint, a measuring and displaying unit, an air flow meter, a first pressure/temperature sensor and an EGR valve opening controller, the test unit comprises an EGR valve, an EGR cooler, an EGR pipeline and a differential pressure base which are connected in sequence, the exhaust gas simulator is connected to the EGR valve through an intake pulse valve and a crossover joint in sequence, the first pressure/temperature sensor is arranged between the intake pulse valve and the crossover joint, the air flow meter is arranged between the conversion joint and the EGR valve, the signal output end of the first pressure/temperature sensor is electrically connected with the feedback signal input end of the exhaust gas simulation device, and the control signal output end of the EGR valve opening controller is electrically connected with the control signal input end of the EGR valve.

Preferably, the exhaust gas simulation device comprises a pressure control cabinet and a temperature control cabinet, wherein the pressure control cabinet is used for controlling the exhaust gas pressure before the air inlet pulse valve, and the temperature control cabinet is used for controlling the exhaust gas temperature before the air inlet pulse valve.

Preferably, the system further comprises a second pressure/temperature sensor and a third pressure/temperature sensor, wherein the second pressure/temperature sensor and the third pressure/temperature sensor are respectively arranged at the air inlet end and the air outlet end of the EGR valve.

Preferably, the EGR cooler further comprises a temperature sensor and a differential pressure sensor, wherein the temperature sensor is arranged on an EGR pipeline behind the EGR cooler, a first interface of the differential pressure sensor is connected with an air inlet end of the differential pressure base, and a second interface of the differential pressure sensor is connected with an air outlet end of the differential pressure base.

Preferably, the test device further comprises a fresh air simulation device, a mixer and a pressure control cabinet, the air outlet end of the fresh air simulation device and the air outlet end of the test unit are both connected to the air inlet end of the mixer, the air outlet end of the mixer is connected with the air inlet end of the pressure control cabinet, and the air outlet end of the pressure control cabinet is communicated with the atmosphere.

Preferably, the air inlet pulse valve adopts a butterfly valve structure and is used for outputting airflow in a pulse mode.

Preferably, the air outlet end of the adapter is connected with an air inlet pipeline of the EGR valve through a V-shaped clamp.

The invention also provides a calibration method, which is an EGR flow correction coefficient calibration method and comprises the following steps:

the EGR valve opening controller controls the EGR valve to open to a specified opening;

acquiring air flow meter data, differential pressure sensor data, engine intake pressure data and EGR cooled exhaust gas temperature data under the current opening degree;

and calibrating an EGR flow correction coefficient under the current opening degree by taking the EGR flow data equal to the air flow meter data under the current opening degree as a target.

Preferably, the method further comprises the following steps:

the EGR valve opening controller controls the EGR valve to be opened to different opening positions between 0 and 100 in sequence;

acquiring EGR flow correction coefficients of the EGR valve under different opening degrees;

and obtaining an EGR flow correction coefficient calibration table based on EGR flow correction coefficients of different opening degrees of the EGR valve.

The invention has the beneficial effects that: the device does not need to build an engine bench, can realize EGR valve flow capacity test, EGR valve temperature and pressure drop test and EGR flow correction coefficient calibration, and saves a large amount of time for project development.

1. The exhaust gas simulation device enters the measuring and displaying unit through the air inlet pulse valve and the adapter, the EGR valve is controlled to be in different opening degrees through the EGR valve opening degree controller, flow values of the EGR valve in different opening degrees are tested through the air flow meter, and the EGR valve flow capacity test of the exhaust gas recirculation system of the internal combustion engine is achieved.

2. The pressure and temperature drop test of the EGR valve can be realized through the second pressure/temperature sensor and the third pressure/temperature sensor which are arranged at the air inlet end and the air outlet end of the EGR valve.

3. The EGR flow correction coefficient calibration under different opening degrees can be realized by controlling the EGR valve to be in different opening degrees based on the EGR valve opening degree controller through the temperature sensor arranged behind the EGR cooler and the differential pressure sensor arranged in front of and behind the differential pressure base.

Drawings

FIG. 1 is a schematic connection diagram of a functional testing device of an exhaust gas recirculation system of a combustion engine according to the present invention;

FIG. 2 is a schematic diagram of the pressure and temperature feedback control of the present invention;

FIG. 3 is a schematic diagram showing the comparison between the pulse signal of the testing table and the actually measured pulse signal of the engine according to the present invention;

FIG. 4 is a schematic view of a V-clamp connection of the present invention;

FIG. 5 is a schematic diagram of an EGR valve flow capacity test;

FIG. 6 is a schematic comparing engine calibration and test bench calibration of EGR flow correction factor.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, refer to an orientation or positional relationship illustrated in the drawings for convenience in describing the present application and to simplify description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Fig. 1 shows a schematic structural diagram of a device for testing the function of an exhaust gas recirculation system of an internal combustion engine provided in a preferred embodiment of the present application (fig. 1 shows a first embodiment of the present application), and for convenience of description, only the parts related to the present embodiment are shown, and the details are as follows:

the device comprises an exhaust gas simulation device 1, an intake pulse valve 3, a crossover joint 4, a measuring and displaying unit 5, an air flow meter 8, a first pressure/temperature sensor 6 and an EGR valve opening controller. The test unit 5 comprises an EGR valve 10, an EGR cooler 11, an EGR line 12 and a differential pressure mount 13 connected in sequence. The exhaust gas simulation device 1 is connected to the EGR valve 10 through an intake pulse valve 3 and a crossover joint 4 in this order. The first pressure/temperature sensor 6 is provided between the intake pulse valve 3 and the crossover joint 4, and the air flow meter 8 is provided between the crossover joint 4 and the EGR valve 10.

As shown in fig. 2, the signal output terminal of the first pressure/temperature sensor 6 is electrically connected to the feedback signal input terminal of the exhaust gas simulation apparatus 1, and the control signal output terminal of the EGR valve opening controller is electrically connected to the control signal input terminal of the EGR valve 10.

The first pressure/temperature sensor 6 measures the temperature and pressure entering the test unit, feeds the temperature and pressure values back to the pressure control cabinet 101 and the temperature control cabinet 102, compares the temperature and pressure values with set values, and automatically adjusts the pressure and pressure values through an internal program of the control cabinet after deviation occurs. The pressure control cabinet 101 can pressurize the gas to 400Kpa at most, and the temperature control cabinet 102 adopts a Regenerative Thermal Oxidizer (RT 0 for short) to heat the gas to 700 ℃ at most and stabilize continuously.

Preferably, the exhaust gas simulation device 1 comprises a pressure control cabinet 101 and a temperature control cabinet 102, wherein the pressure control cabinet 101 is used for controlling the exhaust gas pressure before the air inlet pulse valve 3, and the temperature control cabinet 102 is used for controlling the exhaust gas temperature before the air inlet pulse valve 3.

Preferably, the system further comprises a second pressure/temperature sensor 7 and a third pressure/temperature sensor 9, wherein the second pressure/temperature sensor 7 and the third pressure/temperature sensor 9 are respectively arranged at the air inlet end and the air outlet end of the EGR valve.

Preferably, the EGR cooler further comprises a temperature sensor 14 and a differential pressure sensor 15, wherein the temperature sensor 14 is arranged on the EGR pipeline 12 behind the EGR cooler 11, a first interface of the differential pressure sensor 15 is connected with an air inlet end of the differential pressure base 13, and a second interface of the differential pressure sensor 15 is connected with an air outlet end of the differential pressure base 13.

Preferably, the device also comprises a fresh air simulator 2, an air flow meter 16, a mixer 17 and a pressure control cabinet 18. The air outlet end of the fresh air simulation device 2 and the air outlet end of the test unit 5 are both connected to the air inlet end of a mixer 17, the air outlet end of the mixer 17 is connected with the air inlet end of a pressure control cabinet 18, and the air outlet end of the pressure control cabinet 18 is communicated with the atmosphere. The fresh air simulation apparatus 2 includes a pressure control cabinet 201 and a temperature control cabinet 202.

The fresh air simulator 2 presses fresh air into the mixer to be mixed with the tested gas, and the tested gas is subjected to pressure reduction treatment and then is exhausted into the atmosphere through the pressure control cabinet 18.

The pressure/temperature sensor in this embodiment refers to a pressure sensor that can test the pressure of gas by the pressure sensor and a temperature sensor that can test the temperature of gas by the temperature sensor.

The air flow meter in the embodiment adopts ultrasonic air flow, and the measuring range is 0-600 kg/h.

As shown in fig. 3, the intake pulse valve 3 is of a butterfly valve structure and is used for outputting airflow in a pulse form. The inlet pulse valve 3 heats and pressurizes the fresh air, and the heated and pressurized air is adjusted by the inlet pulse valve to form a pulse signal similar to that of the engine.

As shown in fig. 4, the outlet end of the adapter is connected to the inlet line of the EGR valve by a V-shaped clamp. The exhaust gas recirculation structure can adapt to different types of exhaust gas recirculation structures of different platforms, and different pipeline diameters can be matched according to the recirculation structures of different types.