Numerical investigation for hazardous gas cloud form and dissipation behavior of hydrogen blended natural gas in a confined space

The safety of Hydrogen blended natural gas (HBNG) in confined space is an issue, especially for ventilation process. In this study, leakage and ventilation processes of low pressure HBNG with different hydrogen blended ratio(HBR) in confined space are simulated and validated by experiment based on similarity criteria. For leakage process, the leak direction and HBR does not significantly affect gas accumulation behavior. The required time for gas cloud to fill space decreases slightly with HBR rising and they generally show linear relationship. For ventilation process, the main influences on the leakage process are the total leakage mass and the ventilation conditions. The required time for hazardous gas cloud dissipate increases with total leakage mass and decreases with HBR. For different ventilation conditions, the ranking of required time to exhaust leaked gas is low > center > high > mix. Through the analysis of pressure distribution, it is found time difference is produce..., This study was done using CFD software called fluent. All data were obtained from post-processing of the CFD simulation results. The software chosen for post-processing in this study was Tecplot. The physical variables in the study, except for the hazardous gas cloud volume, can be easily obtained under conditions of some understanding of post-processing. The hazardous gas cloud volume is the sum of the approximate grid volumes, and the method of obtaining it is explained in detail in the manuscript., , # Numerical investigation for hazardous gas cloud form and dissipation behavior of hydrogen blended natural gas in a confined space

[https://doi.org/10.5061/dryad.kh18932h8](https://doi.org/10.5061/dryad.kh18932h8)

## Description of the data and file structure

1 The uploaded data are labeled at the file corresponding to the location in the manuscript.

2 Note that some of the data is on the second and third pages of the xls file

3 For units of data, please refer to the notation in the manuscript

### Files and variables

#### File: fig6.xlsx

**Description:** Comparison of numerical simulation and experiment results. The first column is the leakage time. The second column is the experiment value and the third column is the silumation value. 

##### Variables

* Leakage time-VOL%

#### File: fig7.xlsx

**Description:** CH4 volume fraction variation at monitoring point. The first column is the leakage time. The number in the first row refers to the number of grid cells.

##### Variabl...