Experimental Investigation of Kerosene Spray Flames in Inert Porous Media near Lean Extinction

Abstract

This paper presents a study of kerosene spray flames in inert porous media near lean extinction to understand stable operating regimes. The porous media are composed of silicon-carbide-coated carbon–carbon foam type with 8–25 pores per centimeter and 87% porosity. Two porous media, one in the evaporation section and the other in the combustion section located downstream, are used in the experiments. Aviation-grade kerosene was injected upstream of the evaporation porous medium with an air-blast atomizer. Stable flames were established both inside and on the downstream surface of the combustion porous medium. Results show that, in interior combustion mode, the flame was completely contained within the porous medium until extinction. In the surface combustion mode, a decrease of the fuel flow rate resulted in partial flame lift and subsequent extinction. The equivalence ratio near lean extinction in each mode was determined. A Damkohler number (tres/tchem)-based analysis was developed to study the combustio...