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The flame height behavior of merged or inclined flames from two rectangular fire sources in a parallei configuration and from three and four circular pools of 120mm diameter in a symmetrical configuration were studied experimentally. A rectangular gas diffusion burner, 20 mm x 400 mm or 20 mm x 800 mm was used as line fire sources. Propane gas gave 9.5-57 kW per meter for each burner. Hexane was utilized for the flame merging test using circular pool fires. The height of the flame tip when merged or inclined due to interaction of the flames andlor convective Row was estimated from picture analysis of 300 successive frames of video-recorded data. The flame extension behavior was expressed in dimensionless form as L/Lm =(@*is for square pool fires and L/Lm = ( f 1 ) ' l 3 for rectangular fires. The correction factors offs andf, are&= (nDz+ S ) / n ( D z +S) andf, =(2DW+ S)/2(DW+ S), respectively. When a rectangular or a circular fire source approaches the wall, the same correlation on flame extension behavior was obtained and simulated successfully considering an imaginary fire source inside a wall.

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A reduced-scale experimental study was carried out to collect a knowledge of the effect of external side wind on the flow behavior of a flamelplume which is ejected from an opening of a fire compartment. The external side wind was given to the flamelplume at the various speeds of 0.06misec to 1.88misec. Upward velocities and temperatures of the flamelplume were measured systematically along the wall for vertical and horizontal directions and which gave the trajectory (trace of main flow axis). Decreasing temperature and upward velocity for vertical direction showed similar behavior to those obtained in the flow from a line fire source. The slope of the trajectory inclined by side wind and of which slope was estimated based on the experimental data. A simplified model on the trajectory slope (or flame inclination slope) can be described by the coupled function of dimensionless heat release rate, Froude number and the aspect ratio of the opening base on the balance of buoyancy and inertia force of side wind as well as the aspect ratio of the opening and heat release rate.

Experiments were conducted to characterize the effects of crosswind on flame properties for unconfined fires. Propane gas was used as a fuel in a O.lm XO.lm diffusion burner employed as a model fire source. The effects of the floor around a fire source, which would control the volume of air entrained into the hot current, were also investigated. Empirical models of the apparent flame height of the inclined flame are presented. We also develop empirical models of the flame tilt angle based on the balance of mass fluxes given by the upward hot current and crosswind. These models are based on functions of dimensionless heat release rate and Froude number. The values of empirical coefficients and exponents were derived from the experimental results. The calculated flame length based on the flame tilt angle and the apparent flame height was compared with experimental results, showing that models can be used to estimate flame length in crosswinds .