CN105806886A - Method and device for measuring heat value of gas - Google Patents

Abstract

The invention discloses a method and device for measuring the heat value of gas, and relates to the field of gas measurement.Component analysis is not needed, the process is simple, and the requirement for equipment is low.The method for measuring the heat value of the gas comprises the steps that the measured gas is sampled; the sampled gas is subjected to physical property measurement, and physical property parameters of the gas are obtained; the heat value of the gas is calculated according to the quantitative relation between the heat value and the physical property parameters of the gas.

Description

Gas calorific value measurement method and device

technical field

The invention relates to the field of gas metering, in particular to a method and device for measuring the calorific value of gas.

Background technique

As a common fuel, combustible gas mainly uses the energy released after its combustion, but the current measurement of combustible gas is still based on volumetric or mass measurement, which makes it difficult to reflect the energy value of combustible gas used as fuel. In contrast, the energy measurement method based on the calorific value of combustible gas is more scientific.

The key to the energy measurement of combustible gas is the measurement of calorific value. For multi-component combustible gas, since the calorific value of different types of gas is different, the calorific value is related to the components of the gas. At this stage, it is usually used The gas chromatograph obtains the composition information of the flammable gas to obtain its calorific value. This method needs to sequentially determine the component type and content through component separation, physical property detection and other steps, and then calculate the calorific value of the measured gas according to the component content and component reference calorific value of each component type in the combustible gas. The process is complicated, and the equipment requirements are high, and it is not easy to popularize, which hinders the promotion of flammable gas energy measurement.

Contents of the invention

The invention provides a method and device for measuring the calorific value of gas, which does not require component analysis, has a simple process, and has low requirements for equipment.

In order to achieve the above object, embodiments of the present invention adopt the following technical solutions:

An embodiment of the present invention provides a method for measuring the calorific value of gas, including: sampling the gas to be measured; measuring the physical properties of the gas obtained by sampling to obtain the physical parameters of the gas to be measured; The quantitative relationship calculates the calorific value of the measured gas.

Optionally, the physical parameters include one or more of thermal conductivity, heat capacity, density, viscosity coefficient and thermal diffusivity.

Optionally, the physical parameters include: thermal conductivity and thermal diffusivity; or thermal conductivity and volumetric heat capacity; or thermal conductivity, constant pressure heat capacity and density.

Optionally, before calculating the calorific value of the measured gas according to the quantitative relationship between the gas calorific value and the physical parameter, it also includes: obtaining the quantitative relationship between the gas calorific value and the physical parameter, including: S1 according to the calorific value measurement For the applicable gas range, several standard gases are provided; S2, for any of the standard gases, the calorific value of the standard gas is calculated according to the components of the standard gas, or the calorific value of the standard gas is obtained by direct measurement; and the obtained The physical parameter corresponding to the standard gas; S3, according to the calorific value and physical parameter of several standard gases obtained in step S2, the quantitative relationship between the gas calorific value and the physical parameter is obtained.

Optionally, the description form of the quantitative relationship between the calorific value of the gas and the physical parameters in step S3 is H=p ₀ +∑p _i ×X _i where H is the calorific value of the gas, and X _i is the function of the physical parameters , i is a natural number, p0, p _i are the fitting coefficients of the corresponding quantitative relationship.

Optionally, within the fluctuation range of the following gas components: CH ₄ molar ratio: 79%-100%, C ₂ H ₆ molar ratio: 0-10%, C ₃ H ₈ molar ratio: 0-3%, N ₂ Molar ratio: 0~5%, _CO2 molar ratio: 0~3%; the quantitative relationship between gas calorific value and physical parameters is: H=p0+p1×λ+p2×C _P +p3×ρ among them, H is the calorific value of the gas, λ is the thermal conductivity of the gas, C _p is the heat capacity of the gas at constant pressure, ρ is the gas density, and p0, p1, p2, and p3 are the fitting coefficients of the corresponding quantitative relationships.

The sampling of the gas to be measured specifically includes: sampling the gas to be measured according to a preset sampling period.

Before measuring the physical properties of the gas obtained by sampling, it also includes:

The gas obtained by sampling is pretreated, the temperature of the gas is adjusted to the standard reference temperature, and the pressure of the gas is adjusted to the standard reference pressure.

Optionally, the physical property measurement of the sampled gas is carried out to obtain the physical property parameters of the gas to be measured, specifically: the physical property parameters of the gas to be measured are obtained by detecting changes in the temperature field of the gas under the same thermal excitation conditions.

Optionally, when a physical property sensor is used to measure the physical properties of the sampled gas, the measurement method further includes: using a standard gas with known physical property parameters to correct the physical property sensor, including: obtaining the physical property sensor through the physical property sensor. The physical property parameters of the standard gas; comparing the obtained physical property parameters with the actual corresponding physical property parameter values of the standard gas to obtain a correction factor; and correcting the physical property sensor according to the correction factor.

This embodiment also provides a gas calorific value measurement device, including: a gas collection unit for sampling the gas to be measured; a physical property sensor for measuring the physical properties of the gas obtained by sampling to obtain the physical property parameters of the gas to be measured; The calculation unit calculates the calorific value of the measured gas according to the quantitative relationship between the calorific value of the gas and the physical parameters.

Optionally, the measuring device further includes: a temperature sensor, used to measure the temperature of the gas obtained by sampling; a pressure sensor, used to measure the pressure of the gas obtained by sampling; a preprocessing unit, used to measure the temperature of the gas obtained by sampling The gas is pretreated, the temperature of the gas is adjusted to the standard reference temperature, and the pressure of the gas is adjusted to the standard reference pressure.

Optionally, the measuring device further includes: a preset unit, used to obtain the relationship between the gas calorific value and the physical parameter before calculating the calorific value of the measured gas according to the quantitative relationship between the gas calorific value and the physical parameter Quantitative Relationship.

Existing gas calorific value measurement relies on component analysis, the process is complex and requires high equipment. The method and device for measuring the calorific value of gas provided by the present invention obtain a certain amount of gas to be measured and test the physical parameters of the gas, and then realize the measurement of the calorific value of the gas according to the relationship between the physical parameters and the calorific value. For component analysis, the process is simple, the requirements for equipment are low, and the implementation cost is also low.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For Those of ordinary skill in the art can also obtain other drawings based on these drawings without making creative efforts.

Fig. 1 is the flow chart of the measurement method of gas calorific value that the embodiment of the present invention provides;

Fig. 2 is a schematic diagram of the gas calorific value measurement process provided by the present embodiment;

Fig. 3 is a schematic diagram of the process of obtaining the quantitative relationship between the gas calorific value and the physical parameter in the present embodiment;

Figure 4 is a schematic diagram of a gas calorific value measuring device provided in this embodiment;

Fig. 5 is the second schematic diagram of the gas calorific value measuring device provided in this embodiment.

reference sign

11-gas acquisition unit, 12-physical property sensor, 13-calculation unit, 14-pressure sensor,

15-temperature sensor, 16-preprocessing unit.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention.

For a certain gas (generally refers to a flammable gas or a mixed gas containing a flammable gas, which can be a single-component gas or a multi-component gas mixture), the molecular elements and structures of each component are different. The corresponding physical parameters and calorific values are also different, and each component has a physical parameter and calorific value corresponding to one, that is, the physical parameter X i corresponding to component _i (the physical parameter X _i can be thermal conductivity rate λ _i , heat capacity C _pi , density ρ _i , viscosity μ _i or thermal diffusivity α _i , or multiple items in the above items) and calorific value H _i are unique, so the gas can be detected by The physical parameter X _i , and then according to the relationship between the physical parameter and the calorific value, so as to know its corresponding calorific value H _i .

For multi-component composite gas, its physical properties are related to the physical properties and component content of each component contained. If the number of physical parameters is M and the number of components is N (M, N are both natural numbers), if M≥N-1, the content of the components can be determined by testing the physical properties. For example, the thermal conductivity analysis method is to detect two The mixed thermal conductivity of the known components is known to determine the component content; but if M<N-1, the corresponding specific composition cannot be obtained by the prior art. At this time, it can be determined according to the uniqueness of the physical property combination and The properties of other gases corresponding to the content, thus, the prediction of the calorific value can be realized by detecting the physical properties of the combustible gas, eliminating the miscellaneous steps of component analysis, that is, if the quantitative relationship between the physical parameter Xi and the calorific value is known in advance , the calorific value of the gas can be obtained directly according to the physical parameters.

Based on the above-mentioned principle discussion, an embodiment of the present invention provides a method for measuring the calorific value of gas, as shown in Figure 1 and Figure 2, specifically including:

101. Sampling the gas to be measured. In this step, the measured gas in the pipeline is sampled to obtain a certain amount of measured gas for calorific value measurement, and the measured gas can be returned to the pipeline or directly emptied. The specific sampling method can be any gas sampling method known to those skilled in the art, and the amount of sampling is subject to the physical property measurement in the next step, which is not limited here.

Preferably, this step samples the gas to be measured according to a certain sampling period, which can not only reflect the change of the calorific value of the gas, but also avoid internal friction in the system due to unnecessary frequent measurement.

102. Perform physical property measurement on the sampled gas to obtain physical property parameters of the gas to be measured. Physical property measurement refers to the measurement of physical and chemical properties, such as thermal conductivity, viscosity and thermal diffusion. The physical parameters include one or more of thermal conductivity, heat capacity, density, viscosity coefficient and thermal diffusivity. In this step, the physical properties of the gas obtained by sampling are measured to obtain the physical parameters of the gas to be measured. The specific measurement method can be any physical property measurement method well known to those skilled in the art. Multiple physical parameters can be obtained by one test, and multiple physical parameters can also be obtained. Different physical parameters were obtained from each measurement.

Specifically, in this step, the above physical parameters can be obtained through physical property sensors. Multiple physical property sensors can be used to measure item by item or one physical property sensor can be used to measure simultaneously. The measurement principle includes but is not limited to the thermal principle, that is, by detecting Changes in the temperature field around the sensor for physical property measurement, in addition. Common methods for measuring thermal conductivity of physical parameters in this field include steady-state method, transient hot-wire method, 3ω method and so on.

103. Calculate the calorific value of the measured gas according to the quantitative relationship between the calorific value of the gas and the physical parameters.

According to step 102, the physical property parameters of the gas to be measured are obtained, and the calorific value of the gas to be measured is calculated through the preset quantitative relationship between the calorific value of the gas and the physical property parameters. The quantitative relationship between the calorific value of the gas described in this step and the physical parameters can be described as: H=f(λ, C _P , ρ, α, μ, ...), where λ is the thermal conductivity and C _P is the heat capacity , ρ is the density, α is the thermal diffusivity, and μ is the viscosity coefficient.

The above gas calorific value measurement method provided by the present invention does not need to analyze the components of the measured gas, while ensuring the accuracy of calorific value measurement, it can reduce the complexity and cost of calorific value detection, and can be widely set, not limited to gas Supply station applies.

It should be noted that, in the above gas calorific value measurement method, if a physical property sensor is used to measure the physical properties of the sampled gas in step 102; in order to make the obtained physical property parameters more accurate, it is usually necessary to use a standard gas with known physical property parameters in advance Correcting the physical property sensor includes: obtaining the physical property parameters of the standard gas through the physical property sensor; comparing the obtained physical property parameters with the actual corresponding physical property parameter values of the standard gas to obtain a correction factor; correcting the physical property sensor according to the correction factor , for specific amendments, reference may be made to the prior art, which will not be repeated here.

In addition, in the step 102 of this embodiment, the physical properties of the sampled gas may be measured directly, not the physical parameters, but the initial physical property signals containing the physical property parameter information. The initial physical property signals can be processed to obtain the physical property parameters; Before the measurement, the physical property measuring device is directly calibrated as a calorific value sensor by using a standard gas with known physical property parameters, so as to realize the calibration of the gas calorific value measuring device. When measuring the subsequent gas calorific value, the calibrated physical property measuring device can be directly used for measurement Gas calorific value. Specifically, if the physical property sensor is used to measure the physical properties of the sampled gas in step 102, in the preset stage, the physical property sensor is used to measure a number of standard gases whose calorific value is known to obtain the initial physical property signal of the standard gas; then According to the measured initial physical property signal and its corresponding standard gas calorific value, the quantitative relationship between the initial physical property signal and the gas calorific value is directly obtained, that is, the physical property sensor is directly calibrated as a calorific value sensor, so as to realize The calibration of the gas calorific value measuring device does not need to calibrate the physical property sensor, which avoids the calorific value measurement deviation caused by the calibration accuracy of the physical property sensor.

Preferably, in the above measurement method, after sampling the gas to be tested in step 101, before measuring the physical properties of the gas obtained by sampling in step 102, it also includes: preprocessing the gas obtained by sampling, adjusting the temperature of the gas to the standard reference temperature, the pressure of the gas is adjusted to the standard reference pressure.

Preferably, in order to ensure that the physical property detection environment conditions of the measured gas in different applications are the same in step 102, before the gas obtained by sampling is used for physical property measurement, it is necessary to make the gas pass through the gas temperature and pressure control assembly, and adjust the gas temperature and pressure. Adjusted to the standard reference conditions respectively, the measured gas after temperature and pressure adjustment enters the physical property measurement link in the next step. During specific implementation, the standard reference conditions (standard reference temperature and standard reference pressure) can be determined according to the reference conditions for calorific value calculation. For example, in this step, the gas temperature can be adjusted to a standard reference temperature T ₀ =20° C. (293.15K), and the gas pressure can be adjusted to a standard reference pressure P ₀ =101.325 kPa.

Further, in the above measuring method, before step 103 calculates the calorific value of the measured gas according to the quantitative relationship between the gas calorific value and the physical parameter, it also includes: obtaining the quantitative relationship between the gas calorific value and the physical parameter. The quantitative relationship between the obtained gas calorific value and physical parameters, as shown in Figure 3, this step specifically includes:

S1. Provide several standard gases according to the gas range applicable to gas calorific value measurement. Which standard gas to provide in this step is determined by the applicable gas range, generally determined by the possible components of the gas to be measured and the possible fluctuation range of the components, specifically to be able to obtain the calorific value and physical properties of the gas within the applicable range Quantitative relationships between parameters prevail. In addition, the more groups of standard gases provided in this step, the more data will be obtained, corresponding to the more accurate quantitative relationship between the gas calorific value and physical parameters obtained by data fitting or other methods in the following step S3, but At the same time, the amount of calculation will increase, so this step does not specifically limit the number of standard gas groups provided, and the quantitative relationship between the required gas calorific value and physical property parameters shall prevail.

Generally speaking, in order to obtain an accurate quantitative relationship between the calorific value and physical properties of flammable gases, in principle, all single-component gases of flammable gases should be included, and/or, typical flammable gases in the range of not less than three common components Inflammable gas, the specific selection should generally meet the national or local regulations on the composition and calorific value of "flammable gas".

S2. For any standard gas, calculate the calorific value of the standard gas according to the components of the standard gas, or directly measure the calorific value of the standard gas; and obtain the physical parameters corresponding to the standard gas.

In this step, for the standard gas of any known composition, on the one hand, according to the known composition of the standard gas, according to the calculation method (or other calorific value calculation method) or calorific value of different types of gases stipulated in national standards The measurement method is to obtain the calorific value of the standard gas; on the other hand, to obtain the corresponding physical parameters of the standard gas, preferably, use the method in step 102 (such as using a physical sensor) to measure the physical parameters of the standard gas; it can also be obtained by Consult the relevant data sheet to obtain the corresponding physical parameters of the standard gas. The physical parameters measured here may be one or several of thermal conductivity λ, heat capacity C _P , density ρ, viscosity coefficient μ, and thermal diffusivity α. Generally speaking, the physical parameters in step 102 The parameters are consistent.

S3. According to the calorific value and physical property parameters of several standard gases obtained in step S2, the quantitative relationship between the gas calorific value and the physical property parameters is obtained.

In step S2, the calorific value and physical property parameters corresponding to each standard gas are obtained, and in step S3, based on these data, the quantitative relationship between the gas calorific value and the physical property parameters is obtained by using, for example, a data fitting method. H=f(λ, C _P , ρ, α, μ, ...), the description form of the specific fitting relationship in this step includes but is not limited to:

H=p ₀ +∑p _i ×X _i Wherein, H is the calorific value of the gas, and X _i is a function of physical parameters, where it should be noted that, X _i can be a combination of one or more physical parameters, or X _i is a combination of any one or more of logarithms, exponents or power functions of physical parameters, and the combination can be addition, subtraction, multiplication, division or power relations, i is a natural number, i=1, 2,..., n , p0, p1, ..., pn are the fitting coefficients of the corresponding quantitative relationship.

For example, specifically, the fitting relation description form specifically adopted in this step of data fitting includes but is not limited to: physical property parameters adopt thermal conductivity λ, heat capacity C _P , density ρ and thermal diffusivity α, gas calorific value H= p0+p1×λ+p2×C _P +p3×ρ+p4×α; or, the physical parameters adopt thermal conductivity λ, density ρ and heat capacity C _P , and the calorific value of gas H=p0+p1×λ+p2× ρ×C _P ; or, the physical property parameters adopt thermal conductivity λ and thermal diffusivity α, H=p0+p1×λ+p2×α, or, the physical property parameters adopt thermal conductivity λ, density ρ and heat capacity C _P , H=p0+p1×λ+p2×λ^2+p3×(ρ×C _P ), or the physical property parameters adopt thermal conductivity λ, density ρ and heat capacity C _P , H=p0+p1×λ/ln( λ)+p2×(ρ×C _P ), where H is the calorific value of the gas, p0, p1, p2, p3, and p4 are the fitting coefficients corresponding to the quantitative relationship, and the specific values can be determined by data fitting in step S3 Or regression analysis process to determine.

In a specific implementation, any gas distribution is performed within the fluctuation range of the following flammable gas components (270,000 sets of flammable gas compositions are obtained, and the 270,000 sets of data are used to fit the quantitative relationship), and then the technical solution of the application is simulated and verified.

flammable gas components Fluctuation range (mol%) CH ₄ 79～100 C ₂ H ₆ 0～10 C ₃ H ₈ 0～3 N ₂ 0～5 CO ₂ 0～3

The quantitative relationship between the gas calorific value and the physical property parameters within the fluctuation range of the above-mentioned combustible gas components is obtained by using the standard gas through the above-mentioned steps S1-S3, specifically as follows: H=p0+p1×λ+p2×C _P + p3×ρ, where H is the calorific value of the gas, λ is the thermal conductivity of the gas, C _p is the heat capacity of the gas at constant pressure, and ρ is the gas density. During the specific implementation, due to the difference in the measurement data based on the data fitting, the values of the fitting coefficients p0, p1, p2 and p3 corresponding to the quantitative relationship in the actual fitting may be slightly different. Generally speaking, the value range of p0 is -83.937~-75.943, the value range of p1 is -1325.9~-1199.62, the value range of p2 is 0.04807~0.05313, and the value range of p3 is 71.2519~78.7521.

Experiments have proved that within the range of the above combustible gas components, using the quantitative relationship H==-79.94-1262.76λ+ _0.0506CP +75.002ρ, the calorific value prediction deviation is within ±1.5%. Through statistical analysis, the calorific value measurement deviation of about 95.2% of the sample points is within ±0.5%, and that of 99.6% of the sample points is within ±1.0%.

The gas calorific value measurement method provided by the present invention obtains the quantitative relationship between the gas calorific value and the physical property parameters in advance through the standard gas, and does not need to analyze the components of the gas to be measured, and only needs to measure the physical property parameters of the gas to obtain the measured gas. The calorific value of the gas reduces the complexity and cost of calorific value detection; in addition, the physical property measurement device is calibrated by standard gas to ensure the calorific value measurement accuracy.

This embodiment also provides a gas calorific value measurement device, as shown in Figure 4, the device includes: a gas collection unit 11, used to sample the gas to be measured; The measurement is to obtain the physical parameters of the measured gas; the calculation unit 13 is used to calculate the calorific value of the measured gas according to the quantitative relationship between the gas calorific value and the physical parameters.

The gas calorific value measuring device provided in this embodiment does not need to analyze the components of the measured gas, the process is simple, the requirements for equipment are low, and the implementation cost is also low. The physical parameters include one or more of thermal conductivity, heat capacity, density, viscosity coefficient and thermal diffusivity. If the physical property sensor directly obtains not the physical property parameters, but the initial physical property signal, subsequent signal processing and calculation are required to obtain the physical property parameters, and the module for signal processing and calculation of the initial physical property signal to obtain the physical property parameters can be integrated in the physical property sensor. It can also be integrated in the computing unit 13 . For example, as shown in FIG. 5 , the calculation unit 13 adopts a common single-chip microcomputer or computer. In addition to calculating the calorific value, the calculation unit 13 also has the functions of receiving the initial physical property signal and performing signal processing on the initial physical property signal.

Further optionally, the above measurement device also includes: a temperature sensor 14, used for temperature measurement of the gas obtained by sampling; a pressure sensor 15, used for pressure measurement of the gas obtained by sampling; a preprocessing unit 16, used for The gas obtained by sampling is pretreated, the temperature of the gas is adjusted to the standard reference temperature, and the pressure of the gas is adjusted to the standard reference pressure. As shown in Figure 5, at this time, in addition to calculating the calorific value, the calculation unit 13 also has the function of receiving the initial physical property signal and performing signal processing on the initial physical property signal, and receiving the signals of the temperature sensor 14 and the pressure sensor 15 and performing These signals control the function of the preprocessing unit 16 . Of course, logic control components can also be directly provided at the temperature sensor 14 and the pressure sensor 15 to control the preprocessing unit 16 to adjust the sampled gas to the standard reference temperature and standard reference pressure. Before measuring the physical properties of the gas obtained by sampling, the preprocessing unit 16 first adjusts the temperature and pressure of the gas to the standard reference temperature and standard reference pressure, which can ensure the physical properties of the gas to be tested in different applications. Check the environmental conditions Same, more accurate measurements.

Optionally, the measuring device may further include: a preset unit (not shown in the figure), used to obtain the heat value of the gas before calculating the heat value of the measured gas according to the quantitative relationship between the heat value of the gas and the physical parameters. Quantitative relationship between value and physical parameters. The preset unit may include: a standard gas input device, used to provide several standard gases with known components to the physical property sensor; a standard gas calorific value acquisition module, used for any standard gas, according to the components of the standard gas Calculate the calorific value of the standard gas, or directly measure the calorific value of the standard gas; the physical property sensor is also used to measure the physical parameters corresponding to the standard gas; the data fitting module is used to obtain the calorific value according to the standard gas The calorific value and physical property parameters of several standard gases obtained by the unit and the physical property sensor are used to obtain the quantitative relationship between the gas calorific value and the physical property parameters by means of data fitting. The quantitative relationship between the gas calorific value and physical parameters can be obtained through the preset unit, which provides a calculation basis for the calorific value measurement. This preset step is generally completed before leaving the factory. The preset unit can be set on the measuring device or can be The relative gas calorific value measuring device is set independently, and at this time it is generally set at the production end.

Optionally, the physical property sensor is also used to measure the physical property parameters of the standard gas, and the physical property parameters of the standard gas are known; the measuring device also includes: a correction unit, the physical property parameters obtained by the physical property sensor are actually corresponding to the standard gas The physical property parameter value is compared to obtain a correction factor; and the physical property sensor is corrected according to the correction factor, so that the measurement result is more accurate.

This embodiment provides a gas calorific value measurement device, which does not require component analysis of the measured gas during the measurement process, and the device has a simple structure and low cost.

In addition, the present invention can also use the physical property sensor to obtain the initial physical property signal of the standard gas, and perform quantitative relationship fitting with the calorific value of the corresponding standard gas, so as to directly obtain the quantitative relationship between the initial physical property signal of the physical property sensor and the calorific value, that is, the physical property sensor directly Calibrated as a calorific value sensor, so as to realize the calibration of the combustible gas calorific value measuring device. There is no need to calibrate the physical property sensor, which avoids the calorific value measurement deviation caused by the calibration accuracy of the physical property sensor.

It should be noted that, on the premise of no conflict, the technical features in the embodiments of the present invention can be used in any combination.

In order to facilitate clear description, in the present invention, words such as first and second are used to classify similar items. The first and second words do not limit the present invention in quantity, but are only examples of a preferred mode It should be noted that obvious similar modifications or related extensions conceived by those skilled in the art based on the content disclosed in the present invention all fall within the protection scope of the present invention.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be implemented through computer programs to instruct related hardware, and the programs can be stored in a computer-readable storage medium. During execution, it may include the processes of the embodiments of the above-mentioned methods. Wherein, the storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM) or a random access memory (Random Access Memory, RAM) and the like.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. All should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (13)

1. A gas calorific value measurement method, characterized in that, comprising: Sampling the measured gas; Measure the physical properties of the gas obtained by sampling to obtain the physical parameters of the gas to be measured; Calculate the calorific value of the measured gas according to the quantitative relationship between the calorific value of the gas and the physical parameters. 2. The measurement method according to claim 1, wherein the physical parameters include one or more of thermal conductivity, heat capacity, density, viscosity coefficient and thermal diffusivity. 3. measurement method according to claim 2, is characterized in that, described physical parameter comprises: thermal conductivity and thermal diffusivity; Or, thermal conductivity and volumetric heat capacity; Or, thermal conductivity, heat capacity at constant pressure and density. 4. The measurement method according to claim 1, characterized in that, before calculating the calorific value of the measured gas according to the quantitative relationship between the gas calorific value and the physical parameter, it also includes: obtaining the difference between the gas calorific value and the physical parameter Quantitative relationships among them, including: S1. Provide several standard gases according to the gas range applicable to calorific value measurement; S2. For any of the standard gases, calculate the calorific value of the standard gas according to the components of the standard gas, or directly measure the calorific value of the standard gas; and obtain the corresponding physical parameters of the standard gas; S3. According to the calorific value and physical property parameters of several standard gases obtained in step S2, the quantitative relationship between gas calorific value and physical property parameters is obtained. 5. The measurement method according to claim 4, characterized in that, the description form of the quantitative relationship between the calorific value of the gas and the physical parameters in step S3 is H=p ₀ +∑p _i ×X _i where H is The calorific value of the gas, Xi is a function of physical parameters, _i is a natural number, p0, p _i are the fitting coefficients of the corresponding quantitative relationship. 6. The measuring method according to claim 1, characterized in that, within the fluctuation range of the following gas components: CH ₄ molar ratio: 79% to 100%, C ₂ H ₆ molar ratio: 0 to 10%, C ₃ H ₈ molar ratio: 0-3%, N ₂ molar ratio: 0-5%, CO ₂ molar ratio: 0-3%; the quantitative relationship between gas calorific value and physical parameters is: H=p0+p1×λ+p2×C _P +p3×ρ Among them, H is the calorific value of gas, λ is the thermal conductivity of gas, C _p is the heat capacity of gas at constant pressure, ρ is the density of gas, p0, p1, p2 , p3 is the fitting coefficient of the corresponding quantitative relationship. 7. The measurement method according to any one of claims 1-6, wherein the sampling of the gas to be measured comprises: sampling the gas to be measured according to a preset sampling period. 8. The measurement method according to any one of claims 1-6, characterized in that, before measuring the physical properties of the gas obtained by sampling, it also includes: The gas obtained by sampling is pretreated, the temperature of the gas is adjusted to the standard reference temperature, and the pressure of the gas is adjusted to the standard reference pressure. 9. The measurement method according to any one of claims 1-6, characterized in that, the physical properties of the gas obtained by sampling are measured to obtain the physical parameters of the measured gas, specifically: By detecting the change of the temperature field of the gas under the same heat excitation condition, the physical property parameters of the gas to be measured are obtained. 10. The measurement method according to any one of claims 1-6, wherein when a physical property sensor is used to measure the physical properties of the gas obtained by sampling, the measurement method further comprises: Using a standard gas with known physical parameters to correct the physical property sensor, including: obtaining the physical property parameters of the standard gas through the physical property sensor; Comparing to obtain a correction factor; correcting the physical property sensor according to the correction factor. 11. A gas calorific value measuring device, characterized in that it comprises: A gas collection unit for sampling the gas to be measured; The physical property sensor is used to measure the physical properties of the gas obtained by sampling, and obtain the physical property parameters of the measured gas; The calculation unit calculates the calorific value of the measured gas according to the quantitative relationship between the calorific value of the gas and the physical parameters. 12. The measuring device according to claim 11, further comprising: The temperature sensor is used to measure the temperature of the gas obtained by sampling; The pressure sensor is used to measure the pressure of the gas obtained by sampling; The preprocessing unit is used for preprocessing the gas obtained by sampling, adjusting the temperature of the gas to the standard reference temperature, and adjusting the pressure of the gas to the standard reference pressure. 13. The measuring device according to claim 11, further comprising: The preset unit is used to obtain the quantitative relationship between the gas calorific value and the physical parameter before calculating the calorific value of the measured gas according to the quantitative relationship between the gas calorific value and the physical parameter.