Experimental and numerical study on fire smoke propagation and ventilation modes in powerhouse of hydropower station during construction stage

In this study, full-scale fire experiments and numerical simulations of the underground powerhouse of a hydropower station during the construction stage were performed to investigate the temperature distribution and smoke propagation. The characteristic of inverse ambient temperature in the vertical direction was discovered, resulting in the vertical movement of smoke differing from that in a uniform temperature environment. The maximum temperature increase appeared at non-highest points. Smoke characteristic parameters such as smoke settlement height and temperature increase were discussed at different heat release rates (HRRs) of fire sources to determine the fire risk distribution of the powerhouse. Two ventilation modes were proposed, and their smoke control effects were compared. The optimal ventilation mode and volume in different fire scenarios were proposed. The findings offer scenario and data support for fire smoke control and emergency plan design in powerhouses of hydropower stations.