Investigation of radiation heat transfer in a CAN combustion chamber of a micro gas turbine

Abstract

Thermal radiation plays a key role in heat transfer between the flame and its surroundings. Measuring the radiation flux from the flame in the chamber is challenging due to the impact of the walls. Radiation emitted from the walls and the reflection of flame radiation from the walls interfere with the measurement of flame radiation. In this paper, various parameters that affect flame radiation are investigated. These studies are based on wall incident radiation and wall radiation heat flux. A theoretical method is proposed to calculate the flame radiation and compared it with the CFD simulation results to confirm its accuracy. The DO radiation model and a steady Flamelet combustion model with modified k-ε turbulence have been used to simulate the can-type combustion chamber.  The CFD results were in good agreement with their theoretical ones, and the estimation of flame emission was accurately acceptable. It found out that in the entire temperature range of the wall temperature investigated in this type of combustion chamber, the radiation from the wall never deflects more than 10% of the flame radiation.