A THEORETICAL AND EXPERIMENTAL APPROACH TO HEAT-TRANSFER FROM HIGH-TEMPERATURE GAS FLOWING INSIDE NONHOMOGENEOUS RECTANGULAR PIPES

The purpose of the present paper is to develop a mathematical model fo r predicting thermal field and heat transfer inside short length/heigh t ratio, rectangular and nonhomogeneous material pipe connecting a com bustion chamber with outdoors, while the gas combustion temperatures a re in the range of 2 000 to 3 000 K and the pipe is made of heat-resis tant: material, The used approach is based on a finite difference simu lation and makes certain idealizations and approximations in order to get to an engineering workable and at the same time adequate, solution . Main assumptions are an equivalent temperature cavity to describe ra diant heat transfer due to both the combustion chamber luminous name a nd outdoors. The proposed model shows a very good agreement with exper imental results coming from an experimental set-up used for materials testing, that is embodied in a refractory rectangular pipe, at high te mperature. (C) Elsevier, Paris.