阅读说明：本技术 一种液氢容器内氢质量的计量方法 (Method for measuring hydrogen mass in liquid hydrogen container ) 是由 倪中华 严岩 李仕豪 韩锋 于 2021-01-29 设计创作，主要内容包括：本发明公开了一种液氢容器内氢质量的计量方法,包括建立液氢容器内液态氢质量计量模型和气态氢质量计量模型的过程。包括4个步骤：S1：读取液氢容器内液位计的参数、读取液氢容器气相区的压力参数、确定有效容积；S2：建立液态氢质量计量模型,并将步骤S1获得的参数代入到式(1)中,计算出P小于氢临界压力时的液态氢质量；S3：通过式(2)建立气态氢质量计量模型；S4：通过式(3)计算出液氢容器内的氢质量。本发明能够对液氢容器内氢的质量进行有效的计量。(The invention discloses a method for measuring the mass of hydrogen in a liquid hydrogen container, which comprises the process of establishing a liquid hydrogen mass measurement model and a gaseous hydrogen mass measurement model in the liquid hydrogen container. The method comprises 4 steps: s1: reading parameters of a liquid level meter in the liquid hydrogen container, reading pressure parameters of a gas phase area of the liquid hydrogen container, and determining an effective volume; s2: establishing a liquid hydrogen mass metering model, substituting the parameters obtained in the step S1 into the formula (1), and calculating the mass of the liquid hydrogen when P is smaller than the critical pressure of the hydrogen; s3: establishing a gaseous hydrogen mass metering model by the formula (2); s4: the mass of hydrogen in the liquid hydrogen container was calculated by equation (3). The invention can effectively measure the mass of hydrogen in the liquid hydrogen container.)

1. A method for measuring the mass of hydrogen in a liquid hydrogen container is characterized in that: the method comprises the steps of establishing a liquid hydrogen quality measurement model in a liquid hydrogen container (1) and establishing a gaseous hydrogen quality measurement model, and specifically comprises the following steps:

s1: the following parameters were determined: the liquid level height H of liquid hydrogen in the liquid hydrogen container (1) and the effective volume V of the liquid hydrogen container (1)_tankPressure parameter P of gas phase zone of liquid hydrogen container (1)₀；

S2: establishing a liquid hydrogen mass metering model by using the formula [1], and substituting the parameters obtained in the step S1 into the formula [1], thereby calculating the mass of the liquid hydrogen in the liquid hydrogen container:

M_liquid＝V_liquid(H)*D_liquid(P₀) [1]

formula [1]In, M_liquidMass of liquid hydrogen, V_liquid(H) As a function of the volume of liquid hydrogen with respect to the height H of the liquid surface, D_liquid(P₀) Pressure parameter P for liquid hydrogen density in gas phase zone₀A function of (a);

s3: establishing a gaseous hydrogen mass metering model by using the formula [2], and substituting the parameters obtained in the step S1 into the formula [2], thereby calculating the mass of the gaseous hydrogen in the liquid hydrogen container (1):

M_vapor＝(V_tank-V_liquid(H))*D_vapor(P₀) [2]

formula [2]]In, M_vaporBeing mass of gaseous hydrogen, D_vapor(P₀) Pressure parameter P for gaseous hydrogen density in relation to gas phase zone₀A function of (a);

s4: the total mass of hydrogen in the liquid hydrogen container (1) is calculated by the formula [3 ]:

M_hydrogen＝M_liquid+M_vapor [3]

formula [3]In, M_hydrogenIs the total mass of hydrogen in the vessel.

2. A method of metering the mass of hydrogen in a liquid hydrogen container as claimed in claim 1, wherein: in the step S2, the density D of liquid hydrogen_liquid(P₀) Passing formula [4]And [5 ]]And calculating to obtain:

D_liquid(P₀)＝refpropm(‘D’，‘T’，T_sat-liquid，‘P’，P₀，‘hydrogen’) [4]

T_sat-liquid＝refpropm(‘T’，‘P’，P₀，‘Q’，0，‘hydrogen’) [5]

formula [4]、[5]The reffpropm function in the system is a function in the NIST (national standard database software); t is_sat-liquidIs P₀Liquid under pressureThe hydrogen saturation temperature.

3. A method of metering the mass of hydrogen in a liquid hydrogen container as claimed in claim 2, wherein: in the step S3, the density D of the gaseous hydrogen_vapor(P₀) Through type [6]And [7 ]]And calculating to obtain:

D_vapor(P₀)＝refpropm(‘D’，‘T’，T_sat-vapor，‘P’，P₀，‘hydrogen’) [6]

T_sat-vapor＝refpropm(‘T’，‘P’，P₀，‘Q’，1，‘hydrogen’) [7]

formula [6 ]]、[7]Middle T_sat-caporFor the gas phase zone, the pressure parameter is P₀Gaseous hydrogen saturation temperature under conditions of (a).

4. A method of metering the mass of hydrogen in a liquid hydrogen container as claimed in claim 3, wherein: a function V of the volume of liquid hydrogen in said steps S2 and S3_liquid(H) Function V when using differently shaped containers in relation to the shape of the container_liquid(H) The expressions of (a) and (b) are different from each other.

5. A method of metering the mass of hydrogen in a liquid hydrogen container as claimed in claim 4, wherein: in the step S1, the liquid level H of the liquid hydrogen in the liquid hydrogen container (1) is measured by a liquid level meter (2) provided in the liquid hydrogen container (1).

6. A method of metering the mass of hydrogen in a liquid hydrogen container as claimed in claim 5, wherein: in the step S1, the pressure parameter P of the gas phase area of the liquid hydrogen container (1)₀Obtained by measurement of a pressure sensor (3) arranged in the liquid hydrogen container (1).

Technical Field

The invention relates to the technical field of liquid hydrogen storage, in particular to a method for measuring the mass of hydrogen in a liquid hydrogen container.

Background

The hydrogen can be widely applied to the fields of fuel cell power generation, nuclear fusion energy production, direct combustion heat production and the like. At present, the technical bottleneck of hydrogen energy application mainly lies in the storage and transportation of hydrogen, and particularly, the efficient, safe and long-term storage of hydrogen energy is realized.

The traditional hydrogen storage methods mainly comprise high-pressure gas storage, low-temperature liquid storage and metal compound hydrogen storage. The high-pressure gaseous hydrogen storage energy density is low; the low-temperature liquid hydrogen storage has high cost, no damage and limited storage time, and low small-scale use price ratio, and is mainly used for large-scale liquid hydrogen plants; the hydrogen storage of the compound is difficult to be popularized due to the fact that the hydrogen absorption and desorption conditions of the compound are severe, the hydrogen storage density of the storage mass is too low and the like, which are difficult to meet the practical application.

With the progress of liquid hydrogen container manufacturing technology, as an optimized hydrogen storage means, people combine high-pressure gaseous hydrogen storage and low-temperature liquid hydrogen storage technologies, and develop a low-temperature high-pressure hydrogen storage container, the pressure resistance of the liquid hydrogen storage and transportation container rapidly rises and reaches or even exceeds the critical pressure (1.298MPa) of hydrogen, and the mass metering of liquid hydrogen and gaseous hydrogen in the liquid hydrogen container is always a difficult problem in the technical field of hydrogen storage.

For a general low-pressure liquid hydrogen container, the liquid level height of liquid hydrogen is generally measured by a liquid hydrogen level meter in the prior art, the liquid hydrogen level height is converted into volume according to the shape of the container, and then the density (70.9 kg/m) of the liquid hydrogen at the temperature of 20.2K (the liquefaction temperature of the hydrogen under the standard atmospheric pressure) is combined³) The mass of liquid hydrogen is calculated and the mass of gaseous hydrogen in the vessel is generally negligible. The metering mode can obtain more accurate hydrogen quality when facing a low-pressure liquid hydrogen container, however, when a novel low-temperature high-pressure liquid hydrogen storage and transportation container is adopted, the critical pressure (1.298MPa) of hydrogen in the container is reached and even exceeded, and if the traditional liquid level meter is still used for metering, a huge error is caused because: 1) the saturation temperature of hydrogen also rises with the rise of the hydrogen storage pressure, which means that the temperature of liquid hydrogen rises with the rise of the pressure, and taking 0.1MPa to 1.25MPa as an example, the saturation temperature of liquid hydrogen rises from 20.3K to 32.9K, and the corresponding density of liquid hydrogen is 70.9kg/m³The temperature is reduced to only 39.9kg/m³However, the gas-liquid two-phase characteristics still remain in the container at this time, and if the mass is calculated by combining the density of the liquid hydrogen at the temperature of 20.2K with the parameters of the liquid level meter, the metering of the liquid hydrogen generates huge deviation; 2) the density of the gaseous hydrogen will also increase with increasing hydrogen storage pressure, e.g. from 0.1MPa to 1.25MPa, the density of the gaseous hydrogen will be from 1.3kg/m³Increased to 22.9kg/m³Are the same asThe mass of gaseous hydrogen stored in the gas phase space is greatly increased and can not be ignored according to the traditional method any more, and the gaseous hydrogen needs to be included in the whole metering range of the hydrogen storage container.

Disclosure of Invention

The invention aims to provide a method for measuring the mass of hydrogen in a liquid hydrogen container, which can effectively measure the mass of the hydrogen in the liquid hydrogen container, aiming at overcoming the defects of the prior art.

In order to solve the technical problems, the invention provides the following technical scheme:

a method for measuring the mass of hydrogen in a liquid hydrogen container is characterized in that: the method comprises the steps of establishing a liquid hydrogen mass metering model in a liquid hydrogen container and a gaseous hydrogen mass metering model, and specifically comprises the following steps:

s1: the following parameters were determined: liquid level height H of liquid hydrogen in liquid hydrogen container and effective volume V of liquid hydrogen container_tankPressure parameter P of gas phase zone of liquid hydrogen container₀；

S2: establishing a liquid hydrogen mass metering model by using the formula [1], and substituting the parameters obtained in the step S1 into the formula [1], thereby calculating the mass of the liquid hydrogen in the liquid hydrogen container:

M_liquid＝V_liquid(H)*D_liquid(P₀) [1]

formula [1]In, M_liquidMass of liquid hydrogen, V_liquid(H) As a function of the volume of liquid hydrogen with respect to the height H of the liquid surface, D_liquid(P₀) Pressure parameter P for liquid hydrogen density in gas phase zone₀A function of (a);

s3: establishing a gaseous hydrogen mass metering model by using the formula [2], and substituting the parameters obtained in the step S1 into the formula [2], thereby calculating the mass of the gaseous hydrogen in the liquid hydrogen container:

M_vapor＝(V_tank-V_liquid(H))*D_vapor(P₀) [2]

formula [2]]In, M_vaporBeing mass of gaseous hydrogen, D_vapor(P₀) Pressure parameter P for gaseous hydrogen density in relation to gas phase zone₀A function of (a);

s4: the total mass of hydrogen in the liquid hydrogen container is calculated by the formula [3 ]:

M_hydrogen＝M_liquid+M_vapor [3]

formula [3]In, M_hydrogenIs the total mass of hydrogen in the vessel.

Further, in the step S2, the density D of the liquid hydrogen_liquid(P₀) Passing formula [4]And [5 ]]And calculating to obtain:

D_liquid(P₀)＝refpropm(‘D’，‘T’，T_sat-liquid，‘P’，P₀，‘hydrogen’) [4]

T_sat-liquid＝refpropm(‘T’，‘P’，P₀，‘Q’，0，‘hydrogen’) [5]

formula [4]、[5]The reffpropm function in the system is a function in the NIST (national standard database software); t is_sat-liquidIs P₀Liquid hydrogen saturation temperature under pressure conditions.

Further, in the step S3, the density D of the gaseous hydrogen_vapor(P₀) Through type [6]And [7 ]]And calculating to obtain:

D_vapor(P₀)＝refpropm(‘D’，‘T’，T_sat-vapor，‘P’，P₀，‘hydrogen’) [6]

T_sat-vapor＝refpropm(‘T’，‘P’，P₀，‘Q’，1，′hydrogen’) [7]

formula [6 ]]、[7]Middle T_sat-caporFor the gas phase zone, the pressure parameter is P₀Gaseous hydrogen saturation temperature under conditions of (a).

Further, in the steps S2 and S3, V is a function of the volume of the liquid hydrogen_liquid(H) Function V when using differently shaped containers in relation to the shape of the container_liquid(H) The expressions of (a) and (b) are different from each other.

Further, in the step S1, the liquid level H of the liquid hydrogen in the liquid hydrogen container is measured by a liquid level meter disposed in the liquid hydrogen container.

Further, in the step S1, the pressure parameter P of the gas phase region of the liquid hydrogen container₀Obtained by measurement by a pressure sensor arranged inside the liquid hydrogen container.

Compared with the prior art, the invention has the beneficial effects that: 1. the invention can respectively calculate the mass of liquid hydrogen and gaseous hydrogen under different pressures and working conditions based on the physical property change rule of gas-liquid two-phase hydrogen under different pressures, and construct a calculation model, thereby accurately obtaining the total mass of hydrogen in the liquid hydrogen container and helping operators to better use the liquid hydrogen container from the aspects of economy and safety. 2. Relevant parameters obtained by combining a liquid hydrogen level meter and a pressure sensor arranged in the container can be brought into the quality calculation model in real time, and the change condition of the hydrogen quality in the liquid hydrogen container can be known in real time.

Drawings

FIG. 1 is a schematic diagram of the mass metering method of hydrogen in a liquid hydrogen container according to the present invention;

FIG. 2 is a schematic diagram of the variation of the density of liquid hydrogen in a liquid hydrogen container with the operating pressure;

fig. 3 is a graph showing the change of density of gaseous hydrogen in a liquid hydrogen container with the operating pressure.

Wherein: 1-a liquid hydrogen container; 2-a liquid level meter; 3-pressure sensor.

Detailed Description

For the understanding of the present invention, the following detailed description will be given with reference to the accompanying drawings, which are provided for the purpose of illustration only and are not intended to limit the scope of the present invention.

A method for measuring the mass of hydrogen in a liquid hydrogen container comprises the steps of establishing a liquid hydrogen mass measurement model in the liquid hydrogen container and establishing a gaseous hydrogen mass measurement model, and specifically comprises the following steps:

s1: the following parameters were determined: liquid level height H of liquid hydrogen in liquid hydrogen container 1, and effective volume V of liquid hydrogen container 1_tankPressure parameter P of gas phase zone of liquid hydrogen container 1₀；

S2: establishing a liquid hydrogen mass metering model by using the formula [1], and substituting the parameters obtained in the step S1 into the formula [1], thereby calculating the mass of the liquid hydrogen in the liquid hydrogen container:

M_liquid＝V_liquid(H)*D_liquid(P₀) [1]

formula [1]In, M_liquidMass of liquid hydrogen, V_liquid(H) As a function of the volume of liquid hydrogen with respect to the height H of the liquid surface, D_liquid(P₀) Pressure parameter P for liquid hydrogen density in gas phase zone₀A function of (a);

s3: establishing a gaseous hydrogen mass metering model by using the formula [2], and substituting the parameters obtained in the step S1 into the formula [2], thereby calculating the mass of the gaseous hydrogen in the liquid hydrogen container:

M_vapor＝(V_tank-V_liquid(H))*D_vapor(P₀) [2]

formula [2]]In, M_vaporBeing mass of gaseous hydrogen, D_vapor(P₀) Pressure parameter P for gaseous hydrogen density in relation to gas phase zone₀A function of (a);

s4: the total mass of hydrogen in the liquid hydrogen container is calculated by the formula [3 ]:

M_hydrogen＝M_liquid+M_vapor [3]

formula [3]In, M_hydrogenIs the total mass of hydrogen in the vessel.

Preferably, in step S2, the density D of liquid hydrogen_liquid(P₀) Passing formula [4]And [5 ]]And calculating to obtain:

D_liquid(P₀)＝refpropm(‘D’，‘T’，T_sat-liquid，‘P’，P₀，‘hydrogen’) [4]

T_sat-liquid＝refpropm(‘T’，‘P’，P₀，‘Q’，0，‘hydrogen’) [5]

in step S3, the density of gaseous hydrogen D_vapor(P₀) Through type [6]And [7 ]]And calculating to obtain:

D_vapor(P₀)＝refpropm(‘D’，‘T’，T_sat-vapor，‘P’，P₀，‘hydrogen’) [6]

T_sat-vapor＝refpropm(‘T’，‘P’，P₀，‘Q’，1，‘hydrogen’) [7]

formula [4]～[7]The reffpropm function in (1) is a function in the NIST (national standard database software), T_sat-liquidFor the gas phase zone, the pressure parameter is P₀Liquid hydrogen saturation temperature, T, under operating conditions_sat-caporFor the gas phase zone, the pressure parameter is P₀Gaseous hydrogen saturation temperature under conditions of (a).

Function V of the volume of liquid hydrogen in steps S2 and S3_liquid(H) Function V when using differently shaped containers in relation to the shape of the container_liquid(H) The expressions of (a) and (b) are different from each other.

In step S1, the liquid level H of the liquid hydrogen in the liquid hydrogen container 1 is measured by the liquid level meter 2 disposed in the container, and the pressure parameter P in the gas phase region of the liquid hydrogen container 1 is obtained₀Measured by a pressure sensor 3 arranged in the container.

A specific calculation procedure is listed below for illustration:

the liquid hydrogen container adopts a cylindrical structure with the radius R being 1m and the length L being 10m, two ends of a cylinder body adopt hemispherical seal heads, the liquid level height H of liquid hydrogen in the container is 0.8m, and the pressure P of a gas phase area₀＝0.75MPa。

Volume V of liquid hydrogen_liuquidThe calculation is as follows:

V_liquid＝V_{end socket}+V_{Barrel body}＝33.839m³

Mass M of liquid hydrogen_liquidComprises the following steps:

M_liquid＝V_liquid(H)*refpropm(‘D’，‘T’，T_sat-liquid，‘P’，P₀，‘hydrogen’)＝33.839*55.702＝1884.9kg

mass M of gaseous hydrogen_vaporComprises the following steps:

M_vapor＝(V_tank-V_liquid(H))*refprop(‘D’，‘T’，T_sat-vapor，‘P’，P0，‘hydrogen’)＝1.748*9.5791＝16.74kg

overall mass M of hydrogen_hydrogenComprises the following steps:

M_hydrogen＝M_liquid+M_vapor＝1901.64kg

if the traditional method is adopted to calculate the mass of the liquid hydrogen in the container, the result is as follows:

M_liquid＝V_liquid*D_liquid＝33.839*70.899＝2399.15kg

the error is as high as 26.16%.

Therefore, the beneficial effects of the invention are very obvious.

The above embodiments are merely illustrative of the technical concept and structural features of the present invention, and are intended to be implemented by those skilled in the art, but the present invention is not limited thereto, and any equivalent changes or modifications made according to the spirit of the present invention should fall within the scope of the present invention.