Experimental and Numerical Study of Natural Gas Leakage and Explosion Characteristics

Abstract

Frequent occurrence of indoor natural gas explosion accidents seriously threatens the safety of people and property. To determine the law of indoor natural gas leakage and explosion hazards, based on experiment and simulation, the nature of natural gas explosion, the distribution law of natural gas volume fraction, flame propagation, temperature, and shock wave overpressure were studied. The results show that the flame structure can be divided into three zones, i.e., preheat zone, reaction zone, and product zone. OH + CO ⇔ H + CO 2 is the main exothermic reaction in the combustion process. The overall distribution law of natural gas volume fraction shows that the higher the position, the greater the volume fraction, and the closer the distance to the leak source at the same height, the greater the volume fraction, and the natural gas volume fraction of the hose falling off is the largest under different leakage conditions. The difference in the wrapping structure of the kitchen package has a significant impact on the diffusion distribution of natural gas. The flame development goes through five stages of ignition, slow burning, detonation, slow burning, and extinguishing. The indoor temperature reaches about 1400 °C. Although the simulated value of shock wave overpressure is larger than the experimental value, the relationship between overpressure and distance is expressed by Y = A + B * ln( X + C ). This study can provide certain technical support for natural gas accident rescue. The research can provide certain technical support for natural gas accident rescue and can also be used for accident investigation to form the determination procedure and method of leakage location and leakage amount.

CFD Analysis on the Diffusion and Accumulation Characteristics of Microleakage LPG in an Integrated Stove

“…Some scholars used theoretical models to analyze the diffusion and accumulation characteristics of leakage gases in confined spaces, but they did not fully characterize the short-term variability of concentrations in close proximity to the leakage source. − Whereafter, scholars carried out experiments to further study the diffusion and accumulation characteristics of leakage gas in confined spaces. Cai et al conducted relevant experiments to study the diffusion law after indoor natural gas leakage and the hazards after an explosion and determined the distribution law of indoor natural gas volume fraction under different leakage conditions, as well as the propagation laws of flames and shock waves in an explosion. Brzezińska et al conducted a series of experiments to study the dispersion distribution of leakage LPG in a confined garage, showing that under unventilated conditions, leakage LPG can accumulate on the floor of a confined garage for a prolonged time, creating a high explosion hazard.…”