Case study of fire and explosion accident based on damage consequence and numerical results: Explosion medium traceability

Alcohol-based fuel is widely used in the catering industry due to the excellent economy, but its explosion risk has not been paid much attention in thermal engineering. In this paper, a serious fire accident caused by the leakage of civil alcohol-based fuel vapor in Northeast China is introduced in detail. A case study is carried out by means of on-site investigation and computational fluid dynamics (CFD) technology, and the accurate evaluation and reproduction of the multi-physical field loads are realized. There were two flammable and explosive gas leakage sources, liquefied petroleum gas and alcohol-based fuel, in the building during the accident. Which kind of gas was involved in the explosion process in the early stage of the accident and caused a major fire is an important part of the primary solution of the accident investigation team. In this paper, the damage consequences of the two gases after explosion were effectively restored by CFD. By comparing the on-site damage and numerical results, the explosion medium is identified as the alcohol-based fuel vapor and air explosive mixed gas in the gas cylinder room. The explosion process is that the sparks and high-temperature spatter generated during the welding process of the bracket ignite the methanol-air vapor near the inlet of the fuel tank, and the flame enters the upper gas-phase space of the tank from the inlet pipe and cause the explosion, resulting in a large amount of fuel splashing in the tank and causing fire. The key investigation techniques and research ideas provide an important reference for accident investigation and disaster analysis, and have scientific significance for revealing the accident cause and preventing similar accidents.