Numerical Simulation of Gas Explosion with Non-uniform Concentration Distribution by Using OpenFOAM
Aobo Yang1,2, Yujiao Liu1,2, Ke Gao1,2
1College of Safety Science and Engineering, Liaoning Technical University, Huludao 125105, China.
ACS Omega
|January 1, 2024
Summary
Coal mine gas explosions are dangerous. This study analyzed uneven gas distribution, finding non-uniform explosions propagate faster and have higher pressure growth rates than uniform ones, aiding disaster prevention.
Area of Science:
- Mining Engineering
- Combustion Science
- Computational Fluid Dynamics
Background:
- Coal mine gas explosions pose significant risks, causing casualties and economic losses.
- Uneven gas concentration distribution in mine roadways is common due to gas density being lower than air.
- Understanding these non-uniform explosions is crucial for safety.
Purpose of the Study:
- To analyze the characteristics of gas explosions in mine roadways with uneven gas distribution.
- To investigate the impact of concentration gradients on flame and pressure dynamics.
- To compare non-uniform gas explosions with uniform ones.
Main Methods:
- Utilized the open-source computational fluid dynamics (CFD) code OpenFOAM.
- Simulated and calculated flame and pressure characteristics of gas-air mixtures.
- Analyzed flame and shock wave propagation laws for uniform and non-uniform mixtures.
Main Results:
- Non-uniform gas explosions exhibit higher flame velocities and pressure growth rates than uniform explosions at the same overall concentration.
- Pressure peaks for both uniform and non-uniform explosions were found to be similar.
- A 10% initial volume concentration in non-uniform mixtures resulted in the highest flame propagation velocity and peak values.
- Peak explosion pressure correlated proportionally with the initial concentration gradient.
Conclusions:
- Gas-air mixture explosions with concentration gradients have distinct characteristics compared to uniform mixtures.
- The findings provide theoretical support for developing strategies to prevent and control gas explosion disasters in coal mines.
- CFD simulations offer valuable insights into complex explosion phenomena in mine environments.
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