Influence of turbulence-radiation interaction on radiative heat transfer to furnace wall and temperature distribution in large-scale industrial furnaces enveloping hydrocarbon flame

Abstract

Theoretical examinations based on absorption line databases were carried out to investigate the influence of turbulence-radiation interaction on the radiative heat transfer arriving at the wall of large-scale industrial furnaces including hydrocarbon flame, where the re-absorption of radiative energy by combustion gas on its path toward objects to be heated cannot be neglected. In this study, we combined an improved version of our previous method for reducing the calculation load required for tracing turbulent fluctuation in temperature in great detail and an efficient method proposed in our previous papers to reduce the enormous calculation load contingent on detailed non-gray analysis. When we combined these methods with a governing equation solver for obtaining the spatial distribution of time-averaged values of temperature, concentration, velocity, and so on, we could evaluate the heat transfer including radiation in large-scale industrial furnaces enveloping turbulent hydrocarbon flame with sufficient accuracy equivalent to Line-by-Line analysis and with a feasible calculation load. Our application of this calculation method to large-scale furnaces enveloping hydrocarbon flame revealed that neglecting the turbulence-radiation interaction in numerical simulation gave rise to an obvious change in the heat flux distribution on the side wall and in the spatial distribution of the time-averaged temperature. In addition, change in the total amount of radiative energy arriving at the side wall caused by neglecting the turbulence-radiation interaction was fairly small compared with the change observed in our previous report on a model optical path imaging the typical course of radiative energy in large-scale industrial furnaces fueled by propane.