CN-121980998-A - Hydrogen detonation overpressure calculation method for hydrogen energy ship cabin considering vertical concentration gradient

Abstract

The invention discloses a hydrogen detonation overpressure calculation method for a hydrogen energy ship cabin taking vertical concentration gradients into consideration, relates to the technical field of hydrogen explosion hazard assessment of the hydrogen energy ship cabin, acquires a hydrogen concentration gradient vector in the vertical direction in a ventilation cabin and a height coordinate vector of a hydrogen concentration measuring point, calculates an average hydrogen volume fraction in the ventilation cabin, calculates hydrogen detonation overpressure according to nonuniform hydrogen combustible gas cloud detonation or calculates hydrogen detonation overpressure according to hydrogen release plume ignition according to the average hydrogen volume fraction.

Inventors

• MA HONGSHENG
• WANG CHANGJIAN
• ZHAO HANYU
• DU TAO
• CAO BITENG
• CHEN CHANGBING
• LUO WENTAO
• TANG WEIJIAN

Assignees

• 合肥理工学院

Dates

Publication Date

20260505

Application Date

20260122

Claims (10)

1. 1. The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin by considering the vertical concentration gradient is characterized by comprising the following steps of: S1, acquiring a hydrogen concentration gradient vector C= [ C 1 ,···,c i ,···,c n ] T ] and a height coordinate vector H= [ H 1 ,···,h i ,···,h n ] T ] of a hydrogen concentration measuring point in the vertical direction in the ventilation cabin, wherein i represents an ith hydrogen concentration measuring point in the direction from the lowest position to the highest position, H i is the height coordinate of the ith hydrogen concentration measuring point, C i is the hydrogen concentration at the height coordinate H i , namely the hydrogen concentration of the ith hydrogen concentration measuring point, and n is the total number of the hydrogen concentration measuring points; s2, calculating the average hydrogen volume fraction c ave in the ventilation cabin; And S3, calculating the hydrogen explosion overpressure delta P max in the ventilation cabin according to the average hydrogen volume fraction c ave , wherein if c ave is more than a%, the hydrogen explosion overpressure delta P max is calculated according to heterogeneous hydrogen combustible gas cloud explosion, and if c ave is less than or equal to a%, the hydrogen explosion overpressure delta P max is calculated according to hydrogen release plume ignition, wherein a% is a preset hydrogen volume fraction threshold.
2. 2. The method for calculating hydrogen explosion overpressure of a hydrogen energy ship cabin taking into account vertical concentration gradients as set forth in claim 1, wherein in step S3, the hydrogen explosion overpressure Δp max is calculated according to heterogeneous hydrogen flammable gas cloud explosion, comprising the steps of: S31, calculating a maximum combustion speed S Lmax , and calculating a bottom combustion speed S Lbott of the heterogeneous hydrogen flammable gas cloud according to the average hydrogen volume fraction c ave and the maximum combustion speed S Lmax ; S32, calculating the hydrogen concentration c Lbott corresponding to the bottom combustion speed S Lbott ; S33, calculating the height h Lbott of the bottom of the heterogeneous hydrogen combustible gas cloud; S34, calculating the equivalent thickness h eq and the equivalent radius R eq of the heterogeneous hydrogen combustible gas cloud; S35, calculating the equivalent hydrogen concentration c eq of the heterogeneous hydrogen combustible gas cloud; S36, calculating the laminar flow combustion speed S Leq and the expansion ratio of combustion products according to the equivalent hydrogen concentration c eq ; S37, calculating hydrogen deflagration overpressure delta P max in the ventilation cabin: ; Where P 0 is the ambient pressure, V T is the ventilation chamber volume, Is the hydrogen release flow rate in the ventilation chamber, Is the hydrogen density.
3. 3. The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin taking into account the vertical concentration gradient according to claim 2, wherein the calculation in step S32 is specifically as follows: ; ; Where c i+1 and c i are the hydrogen concentrations at the i+1th and i-th hydrogen concentration measurement points, respectively, S L(i+1) and S L(i) are the combustion speeds calculated from c i+1 and c i , respectively, and the size relationship of S L(i+1) ＞S Lbott ＞S L(i) can be determined from the three size relationships of S Lbott 、S L(i+1) and S L(i) for i and i+1, and S Lbott 、S L(i+1) and S L(i) satisfy the size relationship of S L(i+1) ＞S Lbott ＞S L(i) .
4. 4. The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin taking into account the vertical concentration gradient according to claim 2, wherein the calculation in step S33 is specifically as follows: ; Where c i+1 and c i are the hydrogen concentrations at the (i+1) th and (i) th hydrogen concentration measurement points, respectively, h i+1 and h i are the height coordinates of the (i+1) th and (i) th hydrogen concentration measurement points, respectively, and the hydrogen concentrations c Lbott 、c i+1 and c i satisfy the magnitude relation of c i+1 ＞c Lbott ＞c i .
5. 5. The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin taking into account the vertical concentration gradient according to claim 2, wherein the calculation in step S31 is specifically as follows: ; 。
6. 6. The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin taking the vertical concentration gradient into consideration according to claim 2, wherein the ventilation cabin is a square cavity, and the calculation in step S34 is specifically as follows: h eq =HB-h Lbott ; ; where HB is the height of the ventilation chamber, W is the width of the ventilation chamber, and L is the length of the ventilation chamber.
7. 7. The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin taking into account the vertical concentration gradient according to claim 2, wherein the calculation in step S35 is specifically as follows: c eq =0.5×(c n +c Lbott )。
8. 8. The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin taking into account the vertical concentration gradient according to claim 2, wherein the calculation in step S36 is specifically as follows: ; 。
9. 9. The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin taking the vertical concentration gradient into consideration according to claim 1, wherein the average hydrogen volume fraction c ave =0.5×(c 1 +c n in the ventilation cabin is set, and the preset hydrogen volume fraction threshold a% takes a value of 4.0%.
10. 10. The method for calculating the hydrogen explosion overpressure of the hydrogen energy ship cabin taking the vertical concentration gradient into consideration as set forth in claim 1, wherein in step S3, the explosion overpressure Δp max is calculated according to the ignition of the hydrogen release plume, specifically as follows: The temperature coefficient alpha c is calculated first based on the adiabatic temperature T ad and the initial ambient temperature T 0 within the ventilation chamber, and then based on the ventilation chamber vent area A v and the hydrogen release flow rate The hydrogen deflagration overpressure Δp max is calculated: ; ; In the formula, Is the molar mass of the hydrogen gas, Is the density of the air in the ventilation cabin at normal temperature and normal pressure.

Description

Hydrogen detonation overpressure calculation method for hydrogen energy ship cabin considering vertical concentration gradient Technical Field The invention relates to the technical field of hydrogen explosion disaster assessment of hydrogen energy ship cabins, in particular to a hydrogen explosion overpressure calculation method of hydrogen energy ship cabins considering vertical concentration gradients. Background The hydrogen energy system carried by the hydrogen energy ship can highly integrate links such as hydrogen preparation, purification, compression, power generation and the like in the ship cabin, has the characteristic of industry standardization, and perfectly meets the requirements of hydrogen energy industry development and green shipping industry development. Therefore, hydrogen energy applications on hydrogen energy vessels are receiving attention from the industry. However, it should be noted that hydrogen has the characteristics of small molecular weight, high diffusion speed, low ignition energy, etc., and is extremely prone to gas leakage behavior and accumulation in the upper part of the hydrogen energy ship cabin to form a flammable hydrogen-air cloud. When an ignition source is present in the chamber, the hydrogen jet or flammable hydrogen-air Yun Yi is ignited, producing a hydrogen jet flame burn or deflagration flame propagation, resulting in a significant deflagration overpressure in the chamber. Overpressure loading can cause deformation of the cabin structure, resulting in failure and destruction of the internal hydrogen system and even endangering personnel life safety. Therefore, the method for calculating the explosion and overpressure of the hydrogen in the cabin of the hydrogen energy ship has important engineering value for evaluating the disaster result of the explosion of the cabin hydrogen and guiding the safety design of the cabin structure of the hydrogen energy ship. Although the current industry adopts a method of installing a pressure relief device on a top plate for the hydrogen production cabin and the hydrogen fuel cell cabin by electrolyzing water to reduce the hydrogen explosion result, and can evaluate the hydrogen explosion relief overpressure peak value in the cabin under the condition of the pressure relief device. However, the technology blank is still available in the industry for the method for evaluating the hydrogen explosion overpressure in the ship cabin under the condition of natural ventilation. In addition, the hydrogen explosion overpressure calculation method of the hydrogen-related container reported by the prior technical standard or academic literature is provided for the hydrogen-air mixture explosion process with good premixing and uniform concentration under ideal conditions. However, a non-uniform hydrogen deflagration overpressure calculation method with vertical concentration gradient characteristics, which is closer to the background of a real accident, has not been reported yet. Therefore, how to rapidly evaluate the non-uniform hydrogen deflagration overpressure peak in the cabin under natural ventilation conditions, taking into account the influence of the vertical concentration gradient, is an engineering technical problem that needs to be solved. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides the hydrogen explosion overpressure calculation method for the hydrogen energy ship cabin taking the vertical concentration gradient into consideration, which can rapidly evaluate the uneven hydrogen explosion overpressure peak value in the hydrogen energy ship cabin, and solves the problem that the prior art lacks a hydrogen explosion overpressure evaluation method in the ventilation cabin under the natural ventilation condition. In order to achieve the above purpose, the present invention adopts the following technical scheme, including: The method for calculating the hydrogen deflagration overpressure of the hydrogen energy ship cabin by considering the vertical concentration gradient comprises the following steps: S1, acquiring a hydrogen concentration gradient vector C= [ C 1,···,ci,···,cn]T ] and a height coordinate vector H= [ H 1,···,hi,···,hn]T ] of a hydrogen concentration measuring point in the vertical direction in the ventilation cabin, wherein i represents an ith hydrogen concentration measuring point in the direction from the lowest position to the highest position, H i is the height coordinate of the ith hydrogen concentration measuring point, C i is the hydrogen concentration at the height coordinate H i, namely the hydrogen concentration of the ith hydrogen concentration measuring point, and n is the total number of the hydrogen concentration measuring points; s2, calculating the average hydrogen volume fraction c ave in the ventilation cabin; And S3, calculating the hydrogen explosion overpressure delta P max in the ventilation cabin according to the average hydrogen volum