Influence of ignition area on natural gas explosion in a full-scale typical residential

In order to investigate the influence of potential ignition sources in different rooms on the indoor natural gas explosion characteristics in a real residential environment. In this paper, a full-size physical model of a typical two-bedroom residential house is constructed using FLACS, and a numerical simulation study is carried out. The indoor and outdoor flame propagation characteristics, temperature and overpressure evolution laws under different room ignition conditions are revealed. The results show that the indoor and outdoor flame propagation pattern and speed change significantly with different ignition positions, and the flame development speed is in the order of master bedroom ignition > second bedroom ignition > kitchen ignition > living room ignition > bathroom ignition. The room with the highest indoor temperature is the master bedroom, up to 2337 K. The kitchen room and master bedroom are prone to high overpressure, which is more dangerous. Except for the case of ignition in the master bedroom, the maximum peak overpressure occurs in the master bedroom, the maximum overpressure can be up to 0.721 bar, and there is a large pressure difference with the neighboring rooms; when the ignition position is in the master bedroom, the peak overpressure in the kitchen is up to 0.723 bar. The overall overpressure in the outdoor area rises and then falls with the distance, and the overpressure basically decays to the safe range after 12 m from the window. The research results of this paper can provide a basis for the traceability of indoor natural gas combustion and explosion accidents, as well as residential safety measures.