阅读说明：本技术 基于激光的高温高湿高粉尘高腐蚀环境下的湿度检测方法 (Laser-based humidity detection method under high-temperature, high-humidity, high-dust and high-corrosion environment ) 是由 廖海祁 陈军 蓝权明 刘嘉俊 庄灿宇 张力 于 2019-09-10 设计创作，主要内容包括：本发明公开了一种基于激光的高温高湿高粉尘高腐蚀环境下的湿度检测方法,用于在高温高湿环境下进行湿度检测,方法包括如下步骤：(1)提供一激光光源及一可产生镜面反射的凝露板；(2)通过所述激光光源照射到所述凝露板上产生全反射光,对所述全反射光进行光电转换而产生第一电信号；(3)让所述凝露板在高温高湿环境下产生凝露,并通过所述激光光源照射于所述凝露板上并产生凝露反射光,对所述凝露反射光进行光电转换而产生第二电信号；(4)检测所述凝露板凝露和露散时的温度,确定露点温度；(5)多次重复上述步骤(2)～(4),以得出露点湿度的平均值。本发明是一种能够在高温高湿环境下检测湿度的方法及装置。(The invention discloses a laser-based humidity detection method under a high-temperature, high-humidity, high-dust and high-corrosion environment, which is used for detecting humidity under the high-temperature, high-humidity environment and comprises the following steps: (1) providing a laser light source and a condensation plate capable of generating mirror reflection; (2) irradiating the condensation plate by the laser light source to generate total reflection light, and performing photoelectric conversion on the total reflection light to generate a first electric signal; (3) allowing the condensation plate to generate condensation under a high-temperature and high-humidity environment, irradiating the condensation plate with the laser light source to generate condensation reflected light, and performing photoelectric conversion on the condensation reflected light to generate a second electric signal; (4) detecting the temperatures of the condensation plate during condensation and dispersion and determining the dew point temperature; (5) repeating the steps (2) to (4) for a plurality of times to obtain the average value of the dew point humidity. The invention relates to a method and a device capable of detecting humidity in a high-temperature and high-humidity environment.)

1. A humidity detection method based on laser under high-temperature, high-humidity, high-dust and high-corrosion environment is used for humidity detection under the high-temperature, high-humidity environment, and is characterized by comprising the following steps:

(1) providing a laser light source and a condensation plate capable of generating mirror reflection;

(2) irradiating the condensation plate by the laser light source to generate total reflection light, and performing photoelectric conversion on the total reflection light to generate a first electric signal;

(3) allowing the condensation plate to generate condensation under a high-temperature and high-humidity environment, irradiating the condensation plate with the laser light source to generate condensation reflected light, and performing photoelectric conversion on the condensation reflected light to generate a second electric signal;

(4) detecting the temperatures of the condensation plate during condensation and dispersion by taking the time when the first electric signal and the second electric signal are received as time points, and determining the dew point temperature;

(5) calculating the humidity of the detected environment according to the dew point temperature and the temperature of the detected environment measured in the step (4);

(6) repeating the steps (2) to (5) for multiple times to obtain the average value of the measured ambient humidity.

2. The method for detecting humidity in laser-based environment with high temperature, high humidity, high dust and high corrosion according to claim 1, wherein in step (2), a photoelectric receiver is provided, and the totally reflected light or the condensed reflected light is received by the photoelectric receiver and converted into the first electrical signal or the second electrical signal.

3. The utility model provides a humidity detection device under high wet high dust high corrosion environment of high temperature based on laser which characterized in that includes:

the device comprises a laser light source, a condensation plate capable of generating mirror reflection and a photoelectric receiver, wherein a mirror surface temperature sensor is arranged on one surface of the condensation plate capable of generating mirror reflection;

when the condensation plate is in a dry state, the laser light source irradiates the condensation plate and generates total reflection light on the condensation plate, and the total reflection light passes through the photoelectric receiver and is converted into a first electric signal;

allowing the condensation plate to generate condensation under a high-temperature and high-humidity environment, irradiating the condensation plate by the laser light source to generate condensation reflected light, and converting the condensation reflected light into a second electric signal through the photoelectric receiver;

and detecting the temperatures of the condensation plate during condensation and dispersion by taking the time when the first electric signal and the second electric signal are received as time points, determining the dew point temperature, and calculating the humidity of the detected environment according to the detected dew point temperature and the temperature of the detected environment.

4. The laser-based humidity detection device in the environment with high temperature, high humidity, high dust and high corrosion according to claim 3, further comprising a tubular housing, wherein the incident light guide pipe and the reflected light guide pipe are both disposed inside the tubular housing, and the condensation plate is disposed at a position facing the front side of the tubular housing.

5. The humidity detecting device under the environment of high temperature, high humidity, high dust and high corrosion based on laser as claimed in claim 4, wherein the condensation plate is covered with a gas permeable filtering protective cover for filtering dust.

6. The laser-based humidity detection device in high-temperature, high-humidity, high-dust and high-corrosion environment according to claim 4, wherein the surface of the condensation plate capable of generating specular reflection is a mirror surface, a mirror surface temperature sensor is arranged on the mirror surface, and a smoke temperature sensor is arranged on the back side of the mirror surface.

7. The laser-based humidity detection device in the environment with high temperature, high humidity, high dust content and high corrosion according to claim 3, further comprising an air blowing cooling pipe driven by an air pump, wherein the air blowing cooling pipe can blow air to the mirror surface to adjust the temperature of the mirror surface so that the temperature of the mirror surface is lower than the condensation temperature of smoke.

Technical Field

The invention relates to the technical field of humidity detection, in particular to a method and a device for detecting humidity in a high-temperature, high-humidity, high-dust and high-corrosion environment based on laser.

Background

The smoke and dust flue gas that fixed pollution sources such as chimney discharged has the characteristics of high temperature, high humidity and high dust, and at present, when the humidity of the smoke and dust flue gas that fixed pollution sources such as chimney discharged, when detecting its humidity, almost adopt the resistance-capacitance method, and when the resistance-capacitance method was tested humidity, receive the temperature condition restriction, for example when the ambient temperature of test was higher than a temperature (at present most resistance-capacitance methods were tested humidity, the test temperature that equipment was located can not exceed 200 ℃, the data of the humidity that the resistance-capacitance method tested, and the actual humidity of the environment that is tested had great difference.

When the existing resistance-capacitance method is used for detecting the humidity of fixed pollution sources such as a chimney, a humidity probe is easily polluted by dust in a high-temperature, high-humidity, high-dust and high-corrosion environment, and unnecessary troubles are brought to detection to a certain extent.

In addition, when a resistance-capacitance method is used for humidity testing of fixed pollution sources such as chimneys and the like, humidity testing probes cannot be produced in China at present, the humidity testing probes need to be imported, the price is very high, more than 3000 RMB are arranged on one probe, and the temperature born by the humidity testing probes commonly used at present is within 200 ℃, so that the probes cannot be repaired and damaged easily due to the fact that the temperature is higher than the temperature, and the production cost and the use cost of the whole equipment are greatly increased by a small humidity probe.

Therefore, there is a need for a humidity detection method and apparatus capable of rapidly and accurately detecting humidity without temperature limitation.

Disclosure of Invention

The invention aims to provide a humidity detection method and a humidity detection device which are not limited by temperature and can quickly and accurately detect humidity.

In order to achieve the purpose, the technical scheme provided by the invention is as follows: the method for detecting the humidity under the high-temperature, high-humidity, high-dust and high-corrosion environment based on the laser is used for detecting the humidity under the high-temperature, high-humidity environment and comprises the following steps:

(1) providing a laser light source and a condensation plate capable of generating mirror reflection;

(2) irradiating the condensation plate by the laser light source to generate total reflection light, and performing photoelectric conversion on the total reflection light to generate a first electric signal;

(3) allowing the condensation plate to generate condensation under a high-temperature and high-humidity environment, irradiating the condensation plate with the laser light source to generate condensation reflected light, and performing photoelectric conversion on the condensation reflected light to generate a second electric signal;

(4) detecting the temperatures of the condensation plate during condensation and dispersion by taking the time when the first electric signal and the second electric signal are received as time points, and determining the dew point temperature;

(5) calculating the humidity of the detected environment according to the dew point temperature and the temperature of the detected environment measured in the step (4);

(6) repeating the steps (2) to (5) for multiple times to obtain the average value of the measured ambient humidity.

In the step (2), a photoelectric receiver is provided, and the total reflection light or the condensation reflection light is received by the photoelectric receiver and converted into the first electric signal or the second electric signal.

In order to achieve the second object, the invention provides the following technical scheme: the utility model provides a humidity detection device under high dust high corrosion environment of high temperature and high humidity based on laser includes:

the device comprises a laser light source, a condensation plate capable of generating mirror reflection and a photoelectric receiver, wherein a mirror surface temperature sensor is arranged on one surface of the condensation plate capable of generating mirror reflection;

when the condensation plate is in a dry state, the laser light source irradiates the condensation plate and generates total reflection light on the condensation plate, and the total reflection light passes through the photoelectric receiver and is converted into a first electric signal;

allowing the condensation plate to generate condensation under a high-temperature and high-humidity environment, irradiating the condensation plate by the laser light source to generate condensation reflected light, and converting the condensation reflected light into a second electric signal through the photoelectric receiver;

and detecting the temperatures of the condensation plate during condensation and dispersion by taking the time when the first electric signal and the second electric signal are received as time points, determining the dew point temperature, and calculating the humidity of the detected environment according to the detected dew point temperature and the temperature of the detected environment.

The condensation device is characterized by further comprising a tubular shell, wherein the incident light guide pipe and the reflected light guide pipe are arranged inside the tubular shell, and the condensation plate is arranged right opposite to the front side of the tubular shell.

The outside cladding of condensation board has a ventilative filtration safety cover that is used for filtering the dust.

The condensation plate is characterized in that one surface capable of generating mirror reflection is a mirror surface, a mirror surface temperature sensor is arranged on the mirror surface, and a smoke temperature sensor is arranged on the back side of the mirror surface.

The air blowing cooling pipe can blow air to the mirror surface to adjust the temperature of the mirror surface, so that the temperature of the mirror surface is lower than the condensation temperature of smoke.

Compared with the prior art, in the humidity detection method based on laser under the high-temperature, high-humidity, high-dust and high-corrosion environment, the condensation plate is irradiated by the laser light source to generate total reflection light, and the total reflection light is subjected to photoelectric conversion to generate a first electric signal; allowing the condensation plate to generate condensation under a high-temperature and high-humidity environment, irradiating the condensation plate with the laser light source to generate condensation reflected light, and performing photoelectric conversion on the condensation reflected light to generate a second electric signal; the humidity of the condensation point is calculated through the first electric signal and the second electric signal, so that the detection process is not influenced by the temperature of the test environment, and the detection result can be accurately and quickly output.

The invention will become more apparent from the following description when taken in conjunction with the accompanying drawings, which illustrate embodiments of the invention.

Drawings

FIG. 1 is a block diagram showing the flow of the humidity detection method based on laser in the environment of high temperature, high humidity, high dust and high corrosion.

Fig. 2 is a schematic diagram of an embodiment of a humidity detection device in a high-temperature, high-humidity, high-dust and high-corrosion environment based on laser according to the invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.

The invention discloses a humidity detection method and a humidity detection device under a high-temperature, high-humidity, high-dust and high-corrosion environment. All embodiments of the invention are explained on the premise of detecting the humidity of the smoke dust and smoke gas of the chimney, and certainly, the technical scheme provided by the invention is not limited to detecting the humidity of the smoke dust and smoke gas discharged by the chimney, and can also detect the humidity of other fixed pollution sources, and the conventional technical means, namely a resistance-capacitance method, can not realize a high-temperature high-humidity high-dust high-corrosion environment for detecting the humidity, and can be perfectly realized.

Referring to fig. 1 and 2, a method for detecting humidity in a high-temperature, high-humidity, high-dust and high-corrosion environment based on laser provided by an embodiment of the present invention is used for detecting humidity in a high-temperature, high-humidity environment, and includes the following steps:

s001, providing a laser light source and a condensation plate capable of generating mirror reflection; with reference to fig. 2, the laser light source 1 and the condensation plate 10, the laser light source 1 has the following features: the divergence of the beam is extremely small, on the order of only 0.001 radians, very nearly parallel, whereas the side of the condensation panel 10 that produces specular reflection is specular.

S002, irradiating the condensation plate through the laser light source to generate total reflection light, and performing photoelectric conversion on the total reflection light to generate a first electric signal; referring to fig. 2, a total reflection light guide column 2 may be disposed between the laser light source 1 and the condensation plate 10, the laser light source 1 enters from a rear surface of the total reflection light guide column 2 after passing through an incident light guide tube 3, and then generates a first total reflection through one side of the total reflection light guide column 2, and then exits from a front surface of the total reflection light guide column 2 to irradiate one side of the condensation plate 10, which generates a mirror reflection, the side of the condensation plate 10, which generates the mirror reflection, is a mirror surface, and generates a second total reflection on the mirror surface, at which time the laser light enters from the front surface of the total reflection light guide column 2, and then generates a third total reflection through the other side of the total reflection light guide column 2, and finally exits from the rear surface of the total reflection light guide column 2, so as to better receive the laser light reflected for the second time to perform photoelectric conversion to generate the first electric signal, so that the laser light totally reflected for the third time enters the predetermined reflected light guide 4. And a photoelectric receiver 5 is arranged at the tail end of the reflected light guide pipe 4, and the total reflected light is received by the photoelectric receiver 5 and converted into the first electric signal. It should be noted that the laser light subjected to the third total reflection completes photoelectric conversion in the reflected photoelectric receiver 5 to obtain the first electric signal, and the voltage of the first electric signal is Vf.

S003, enabling the condensation plate to generate condensation under a high-temperature and high-humidity environment, irradiating the condensation plate through the laser light source to generate condensation reflected light, and performing photoelectric conversion on the condensation reflected light to generate a second electric signal;

it should be noted that, because the laser is used as the light source in the present invention, and the laser is used as the light source, the energy of the laser light source is very high, and the light beam is very small, for example, the diameter of the laser spot may be only 1-2 mm, or even smaller, and when the light source is a common light source (after the light is guided through an optical lens to form parallel light, the diameter of the light plate of the parallel light formed by the common light source is about 1 cm), even if the condensation is generated on the condensation plate 10, the condensation reflection is still generated on the laser beam.

In this embodiment, need carry out humidity detection to the smoke and dust flue gas in the chimney, need will combine the condensation board 10 that fig. 2 shows to stretch into and carry out humidity detection in the chimney, when condensation board 10 got into the chimney, the environment in the chimney was high temperature, high wet and the high corrosive environment of high dust, at first need the periphery of condensation board 10 sets up a ventilative filtration safety cover 11 to filter high dust, it is right to avoid high dust condition condensation board 10 produces the interference at the condensation in-process, so set up and can avoid the influence of high dust to humidity detection.

Referring to fig. 2, in this step, once the condensation plate 10 enters the chimney, condensation will be generated on the mirror surface, and total reflection will not be generated, and this is a condensation point, the surface of the condensation point is irregular, so that a part of the laser light source 1 is refracted and then scattered, while the other part still generates reflection after refraction, which is called condensation reflection, and considering the characteristics of the laser light source 1, unlike the characteristics of photodiodes and other light sources, and also in connection with the fact that the thickness of the condensation point is very small in the normal state (if the thickness of the condensation point is accidentally greater, according to the current test standards, this data should be deleted and retested once again to improve the accuracy of the test), the laser beam reflected by the condensation will occupy most of the energy of the laser source 1. Therefore, since the incident point is the condensation point at this time, condensation reflection occurs at the condensation point of the laser light source 1, and condensation reflection light is generated.

With reference to fig. 2, the laser light source 1 generates the first total reflection and the condensation reflection, where the first total reflection may refer to step S002: a total reflection light guide column 2 is arranged between the laser light source 1 and the condensation plate 10, the laser light source 1 enters from the rear surface of the total reflection light guide column 2 after passing through an incident light guide pipe 3, and then generates a first total reflection through one side of the total reflection light guide column 2; condensation reflection: from the front surface of the total reflection light guide column 2, scattered light and condensation reflected light are respectively generated on the mirror surface, and the condensation reflected light can be regarded as the second total reflection generated on the mirror surface; at this time, the laser beam enters from the front surface of the total reflection light guide column 2, then the third total reflection is generated through the other side of the total reflection light guide column 2, and finally the laser beam exits from the rear surface of the total reflection light guide column 2, according to the characteristic that the directivity of the laser beam is very good, through a plurality of experiments, the deviation between the path of the condensed reflected light and the path of the laser beam which is subjected to the third total reflection in the step S002 is small, and the condensed reflected light can be completely received by the same photoelectric receiver 5, so that only one photoelectric receiver 5 needs to be arranged, and therefore the condensed reflected light enters the preset reflected light guide tube 4 through the third total reflection generated through the other side of the total reflection light guide. And reaches the photoelectric receiver 5 arranged at the tail end of the reflected light guide pipe 4, and the condensed reflected light is received by the photoelectric receiver 5 and converted into the second electric signal. Note that, the condensed reflected light is subjected to photoelectric conversion in the photoelectric receiver 5 to obtain the second electrical signal, and the voltage of the second electrical signal is Vz.

In step S002 and step S003, the laser light emitted from the laser light source 1 is reflected three times, and the three times of reflection are total reflection in step S002; in the three reflections of step S003, the first and third reflections are total reflection, and the second reflection is condensation reflection.

S004, detecting the temperatures of the condensation plate during condensation and condensation by taking the time when the first electric signal and the second electric signal are received as time points, and determining the dew point temperature; the temperature of the condensation plate during condensation and the temperature of the condensation plate during condensation are detected through a mirror surface temperature sensor 16 arranged on the mirror surface, the light intensity reflected by the mirror surface is sharply reduced when condensation just occurs, and the temperature of the instantaneous condensation surface is measured, namely the dew point temperature. That is, when the voltage Vf of the first electric signal is sharply decreased and the voltage Vz of the second electric signal is sharply increased, the temperature of the mirror surface is the dew point temperature. If the temperature of the mirror surface is higher than the dew point temperature, the mirror surface is not condensed, the light reflection performance of the mirror surface is good, and scattering is not generated; if the temperature of the mirror surface is lower than the dew point temperature, the mirror surface begins to be condensed, and the mirror surface generates scattering.

S005, calculating the humidity of the detected environment according to the dew point temperature and the temperature of the detected environment measured in the step S004;

s006, repeat above-mentioned step S002-S005 many times to obtain the average value of the ambient humidity of being surveyed, can improve the degree of accuracy that tests greatly.

It should be noted that, referring to fig. 2, a mirror surface temperature sensor 16 is provided on the mirror surface, and a smoke temperature sensor 12 is provided on the back side of the mirror surface. The condensation plate 10 is provided with a smoke temperature sensor 12 and an air blowing cooling pipe 13 for blowing air to the condensation plate 10, the smoke temperature sensor 12 can quickly detect smoke temperature, and the air blowing cooling pipe 13 blows air to the mirror surface to cool the mirror surface. When the temperature data detected by the mirror surface temperature sensor 16 is compared with the temperature data of the smoke temperature detected by the smoke temperature sensor 12, and the temperature difference between the two is smaller than the condition of generating condensation, the air blowing cooling pipe 13 blows air to the mirror surface to cool the mirror surface.

It should be noted that the provision of the blow cooling pipe 13 is also based on the premise that: once the condensation plate 10 enters the chimney, the smoke and dust flue gas with high temperature, high humidity, high dust and high corrosion in the chimney generates condensation on the mirror surface, the voltage for obtaining the second electric signal is Vz at the moment, the condensation on the mirror surface is generated, or the condensation generated at the beginning is volatilized because the temperature of the condensation plate is slowly close to the smoke temperature because the condensation plate 10 enters the chimney for too long time, so the blowing cooling pipe 13 can be arranged, the blowing cooling pipe 13 is used for blowing and cooling the mirror surface, the time point of condensation generated on the mirror surface for many times can be adjusted, and dust adhered on the mirror surface can be blown and cleaned.

It should be noted that the power source of the cooling air needed by the gas blowing cooling pipes 13 is provided by the air pump 1 and the air pump 2 as shown in fig. 2, and the air pump 1 and the air pump 2 can provide a cooling air source for at least two of the gas blowing cooling pipes 13.

It is necessary to provide the heat insulating case 14 on the outside of the condensation plate 10, and the heat insulating case 14 has a very good heat insulating effect against the temperature of the smoke. During detection, the temperature of the mirror surface is adjusted to be lower than the smoke temperature so as to reach the smoke condensation temperature Ta.

It should be noted that the basic principle of measuring relative humidity by the dew point method is as follows: the dew point temperature Ta is measured and then the saturated partial water vapor pressure Pl corresponding to the dew point temperature Ta is determined. As is apparent, Pl is the water vapor pressure of the air to be measured. Therefore, the relative humidity E of the air can be found by the following equation:

and E ═ Pl/Pb 100% Pb is the saturated steam pressure, and Pl is obtained by a table look-up method.

It should be noted that the table lookup to obtain Pl can be implemented by referring to technical literature, and is not described herein again.

Referring to fig. 2, in order to achieve another object, the present invention provides a technical solution: the utility model provides a humidity detection device under high dust high corrosion environment of high temperature and high humidity based on laser includes:

the device comprises a laser light source 1, an incident light guide pipe 3, a reflected light guide pipe 4, a condensation plate 10 capable of generating mirror reflection, and a photoelectric receiver 5.

When the condensation plate 10 is in a dry state, the light source 1 guides light through the incident light guide pipe 3 and irradiates the condensation plate 10, and generates total reflection light on the condensation plate 10, and the total reflection light is transmitted to the photoelectric receiver 5 through the reflection light guide pipe 4 and converted into a first electric signal;

with reference to fig. 2, the laser light source 1 and the condensation plate 10, the laser light source 1 has the following features: the divergence of the light beam is extremely small, about only 0.001 radian, and very close to parallel; and the side of the condensation plate 10 that can produce specular reflection is specular.

Referring to fig. 2, a total reflection light guide column 2 may be disposed between the laser light source 1 and the condensation plate 10, the laser light source 1 enters from a rear surface of the total reflection light guide column 2 after passing through an incident light guide tube 3, and then generates a first total reflection through one side of the total reflection light guide column 2, and then exits from a front surface of the total reflection light guide column 2 to irradiate one side of the condensation plate 10, which generates a mirror reflection, the side of the condensation plate 10, which generates the mirror reflection, is a mirror surface, and generates a second total reflection on the mirror surface, at which time the laser light enters from the front surface of the total reflection light guide column 2, and then generates a third total reflection through the other side of the total reflection light guide column 2, and finally exits from the rear surface of the total reflection light guide column 2, so as to better receive the laser light reflected for the second time to perform photoelectric conversion to generate the first electric signal, so that the laser light totally reflected for the third time enters the predetermined reflected light guide 4. And a photoelectric receiver 5 is arranged at the tail end of the reflected light guide pipe 4, and the total reflected light is received by the photoelectric receiver 5 and converted into the first electric signal. It should be noted that the laser light subjected to the third total reflection completes photoelectric conversion in the reflected photoelectric receiver 5 to obtain the first electric signal, and the voltage of the first electric signal is Vf.

Allowing the condensation plate 10 to generate condensation under a high-temperature and high-humidity environment, wherein the laser light source 1 irradiates a condensation point of the condensation plate 10 through the incident light guide pipe 3 and generates condensation reflected light, and the condensation reflected light passes through the photoelectric receiver 5 and is converted into a second electric signal;

it should be noted that, because the laser is used as the light source in the present invention, and the laser is used as the light source, the energy of the laser light source is very high, and the light beam is very small, for example, the diameter of the laser spot may be only 1-2 mm, or even smaller, and when the light source is a common light source (after the light is guided through an optical lens to form parallel light, the diameter of the light plate of the parallel light formed by the common light source is about 1 cm), even if the condensation is generated on the condensation plate 10, the condensation reflection is still generated on the laser beam.

In this embodiment, need carry out humidity detection to the smoke and dust flue gas in the chimney, need will combine the condensation board 10 that fig. 2 shows to stretch into and carry out humidity detection in the chimney, when condensation board 10 got into the chimney, the environment in the chimney was high temperature, high wet and the high corrosive environment of high dust, at first need the periphery of condensation board 10 sets up a ventilative filtration safety cover 11 to filter high dust, it is right to avoid high dust condition condensation board 10 produces the interference at the condensation in-process, so set up and can avoid the influence of high dust to humidity detection.

Referring to fig. 2, once the condensation plate 10 enters the chimney, condensation occurs on the mirror surface, total reflection does not occur, and at this time, the condensation point is a condensation point, and the surface of the condensation point is an irregular shape, so that a part of the laser light source 1 is refracted and then scattered, and another part of the laser light source 1 is refracted and then still reflected, which is called condensation reflection, and considering the characteristics of the laser light source 1, the characteristics are different from those of a photodiode and other light sources, and the normal thickness of the condensation point is very small (if the thickness of the condensation point is occasionally larger, according to the current test standard, the data should be deleted and retested once again to improve the test accuracy), so that the laser beam generating condensation reflection occupies most of the energy of the laser light source 1. Therefore, since the incident point is the condensation point at this time, condensation reflection occurs at the condensation point of the laser light source 1, and condensation reflection light is generated.

With reference to fig. 2, the laser light source 1 generates the first total reflection and the condensation reflection, wherein the first total reflection can refer to when the condensation plate is in a dry state (i.e. not entering into the chimney): a total reflection light guide column 2 is arranged between the laser light source 1 and the condensation plate 10, the laser light source 1 enters from the rear surface of the total reflection light guide column 2 after passing through an incident light guide pipe 3, and then generates a first total reflection through one side of the total reflection light guide column 2; condensation reflection: from the front surface of the total reflection light guide column 2, scattered light and condensation reflected light are respectively generated on the mirror surface, and the condensation reflected light can be regarded as the second total reflection generated on the mirror surface; at this time, the laser beam enters from the front surface of the total reflection light guide column 2, then the third total reflection is generated through the other side of the total reflection light guide column 2, and finally the laser beam comes out from the rear surface of the total reflection light guide column 2, according to the characteristic that the directivity of the laser is very good, through a plurality of experiments, the deviation between the path of the condensation reflected light and the path of the laser beam of the third total reflection generated by the mirror surface when the condensation plate is dried is small, and the laser beam can be completely received by the same photoelectric receiver 5, so only one photoelectric receiver 5 needs to be arranged, and therefore the condensation reflected light enters the preset reflected light guide tube 4 through the third total reflection generated by the other side of the total reflection light guide column 2. And reaches the photoelectric receiver 5 arranged at the tail end of the reflected light guide pipe 4, and the condensed reflected light is received by the photoelectric receiver 5 and converted into the second electric signal. Note that, the condensed reflected light is subjected to photoelectric conversion in the photoelectric receiver 5 to obtain the second electrical signal, and the voltage of the second electrical signal is Vz.

When the condensation plate 10 is in a dry state or condensation reflection occurs, the laser light emitted by the laser light source 1 passes through three reflections, and the three reflections are total reflections; when the condensation plate 10 generates condensation, the first reflection and the third reflection are total reflection, and the second reflection is condensation reflection.

And detecting the temperatures of the condensation plate during condensation and condensation by taking the moments of receiving the first electric signal and the second electric signal as time points, determining the dew point temperature, detecting the temperatures of the condensation plate during condensation and condensation by a mirror surface temperature sensor 16 arranged on the mirror surface, rapidly reducing the light intensity reflected by the mirror surface when condensation just occurs, and measuring the temperature of the instantaneous condensation surface, namely the dew point temperature. That is, when the voltage Vf of the first electric signal is sharply decreased and the voltage Vz of the second electric signal is sharply increased, the temperature of the mirror surface is the dew point temperature. If the temperature of the mirror surface is higher than the dew point temperature, the mirror surface is not condensed, the light reflection performance of the mirror surface is good, and scattering is not generated; if the temperature of the mirror surface is lower than the dew point temperature, the mirror surface begins to condense, and the mirror surface generates scattering;

calculating the humidity of the detected environment according to the measured dew point temperature and the temperature of the detected environment; the test is repeated to obtain the average value of the humidity of the tested environment, so that the test accuracy can be greatly improved.

It should be noted that, referring to fig. 2, a mirror surface temperature sensor 16 is provided on the mirror surface, and a smoke temperature sensor 12 is provided on the back side of the mirror surface. The condensation plate 10 is provided with a smoke temperature sensor 12 and an air blowing cooling pipe 13 for blowing air to the condensation plate 10, the smoke temperature sensor 12 can quickly detect smoke temperature, and the air blowing cooling pipe 13 blows air to the mirror surface to cool the mirror surface. When the temperature data detected by the mirror surface temperature sensor 16 is compared with the temperature data of the smoke temperature detected by the smoke temperature sensor 12, and the temperature difference between the two is smaller than the condition of generating condensation, the air blowing cooling pipe 13 blows air to the mirror surface to cool the mirror surface.

It should be noted that the provision of the blow cooling pipe 13 is also based on the premise that: once the condensation plate 10 enters the chimney, the smoke and dust flue gas with high temperature, high humidity, high dust and high corrosion in the chimney generates condensation on the mirror surface, the voltage for obtaining the second electric signal is Vz at the moment, the condensation on the mirror surface is generated, or the condensation generated at the beginning is volatilized because the temperature of the condensation plate is slowly close to the smoke temperature because the condensation plate 10 enters the chimney for too long time, so the blowing cooling pipe 13 can be arranged, the blowing cooling pipe 13 can blow and cool the mirror surface, meanwhile, the time point for generating condensation on the mirror surface for many times can be adjusted, and dust adhered on the mirror surface can be blown and cleaned.

It should be noted that the power source of the cooling air needed by the gas blowing cooling pipes 13 is provided by the air pump 1 and the air pump 2 as shown in fig. 2, and the air pump 1 and the air pump 2 can provide a cooling air source for at least two of the gas blowing cooling pipes 13.

It is necessary to provide the heat insulating case 14 on the outside of the condensation plate 10, and the heat insulating case 14 has a very good heat insulating effect against the temperature of the smoke. During detection, the temperature of the mirror surface is adjusted to be lower than the smoke temperature so as to reach the smoke condensation temperature Ta.

It should be noted that the basic principle of measuring relative humidity by the dew point method is as follows: the dew point temperature Ta is measured and then the saturated partial water vapor pressure Pl corresponding to the dew point temperature Ta is determined. As is apparent, Pl is the water vapor pressure of the air to be measured. Therefore, the relative humidity E of the air can be found by the following equation:

and E ═ Pl/Pb 100% Pb is the saturated steam pressure, and Pl is obtained by a table look-up method.

It should be noted that the table lookup to obtain Pl can be implemented by referring to technical literature, and is not described herein again.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented in other ways. The apparatus embodiments described above are merely illustrative, and for example, the flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

In addition, the functional modules in the embodiments of the present invention may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. As another example, directional relational terms such as left, right, upper, lower, and the like may be used solely to refer to those directions as they appear in the drawings, and do not necessarily require or imply any actual such directional relationships between the entities or operations. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.