A study on buoyancy-driven maximum ceiling gas temperature of T-shaped bifurcated channel-like structure in fire environment

Abstract

A study mainly concerning the fire-induced maximum ceiling smoke temperature in T-shaped bifurcated channel-like structure was conducted. A series of model-scale fire tests and full-scale numerical simulations were performed to obtain the maximum ceiling smoke temperature with various heat release rates and branch widths. Results shown that the branch could affect plume entrainment flow in vicinity of fire source. Flame plume would tilt to the proximal sidewall to some extent. With the increase of branch opening, flame plume tilt seems to be greater. The growth trend of central ceiling smoke temperature directly above fire source with burning time can be effectively characterized by power function (Ts∝n1tn2). In current research range of model structure scale and heat release rate, maximum ceiling smoke temperature of T-shaped bifurcated channel slightly decreases with the increase of dimensionless branch width. A corresponding empirical correlation for maximum ceiling smoke temperature in such fire scenario is proposed by associating dimensionless branch width and dimensionless heat release rate. The prediction of empirical correlation could be supported by current measured results in model-scale fire tests and full-scale numerical simulations, as well as the previous scholars' model-scale and full-scale data.