A Numerical Study for Heat Transfer Characteristics of a Micro Combustor by Large Eddy Simulation

Abstract

The characteristics of heat transfer in confined multiple jet flows of a micro can combustor is investigated by means of large eddy simulation (LES). The micro combustor can be employed for a hybrid system, which consists of a micro gas turbine and a solid oxide fuel cell. In the present study, the focus is brought into heat transfer, which has a great effect on combustion stability as heat loss to the outside of combustor. The study is made for the three cases of different baffle plate configurations with changing the velocity ratio between fuel and oxidant jets. Downstream of the baffle plate, the flow recirculation regions appear and they can affect the enhancement of the turbulent heat transfer to the wall. In particular, the near-wall flow recirculation region formed between the oxidant jet and the combustor wall plays an important role for wall heat transfer. We study the turbulent thermal fields and conjugate heat transfer which show peculiar characteristics corresponding to the three different baffle plate shapes and different velocity ratios.