Evaporating Interface in a Capillary Tube With High Heat Flux Induced by Micro Diffusion Flame

Abstract

A series of experiments was conducted to understand the combustion characteristics and evaporating interface behavior of liquid fuel in capillary tubes. The flame shape, interface location of fuel front and tube outer surface temperature was visually observed and measured using CCD and IR camera, respectively. With fuel supply rate increasing, the interface location rose to tube exit and the temperature gradient of the outer tube surface increased, and consequently the evaporating interface tended to be unstable. The prediction of interfacial evaporation using available models was compared with the experimental measurements, indicating that this kind of highly non-equilibrium micro combustion with phase-change could not be described by normal mechanisms.