Modeling of circular counterflow swissroll combustor for MEMS application

Abstract

A two-dimensional numerical model is generated for simulating combustion and heat transfer in "Spiral Swiss roll" combustors. In this research, the most important purpose is to investigate the micro-scale combustion and the extinction limits in such combustors. The momentum, energy, pressure, ideal gas and species equations are numerically modeled for accomplishing this goal. This models couples heat transfer and chemical reaction in the gas and heat diffusion in the conducting walls. Since; there is complexity exists about modeling a Spiral Swiss roll combustor, unwrapped model is preferred for simplicity. Hence; the Spiral Swiss roll geometry is unwrapped in to a straight channel, and the diffusion of heat among the walls is simulated by using heat fluxes and transporting them throughout the geometry. By this way, heat recirculation between the unburnt and burnt gas is taken into consideration appropri- ately. Besides, the effect of Reynolds number, equivalence ratio, wall thickness, wall conductivity constant and channel height on the temperature distribution and chemical reaction rate is investigated. Also, the extinction limits observed for different channel heights and Reynolds numbers. Propane and Methane are selected as fuel. In the code development, the SIMPLE method is used as the main algorithm, and FORTRAN is used.