The Calculation Method Of Radiative Heat Transfer In The Absorption And Scattering Medium Based On The K-distribution Model

The high temperature gas-particle mixture’s thermal radiation is the main form ofheat exchanger in the combustion process, such as engine combustion chamber, nozzle,boiler furnace, the fire and so on. Combustion and radiation are distinctive, radiation hasthe characteristics of full field, non-gray and coupling. There is a complex thermalenvironment in the combustion chamber. The construction of gas and particles’ radiativemodel is a challenge object. The non-gray characteristic of gas and particles makes theradiative heat transfer calculation in the combustion-flow-heat transfer coupled modelspent too much compute time and resources. Therefore, the accurate gas and particlesradiative model is required in the study of high temperature combustion process,especially the efficient means to deal with the non-gray properties of gas and particles.To elevate the computational efficiency, the K-distribution model is the best choice inthe current non-gray gas radiation treatment. The main means of the non-graycharacteristic of particles are still the gray particle approximation and gray bandapproximation. In the background of the radiative heat transfer problem of absorbing andscattering medium in the multi-field coupled circumstance, the purpose of this paper is toestablish the treatment for the non-gray properties of gas and particles, with thecombination of the discrete ordinates method, put forward the K-distribution model forsolving the problem of the absorbing and scattering medium’s radiative heat transfer. Themajor research covers the following aspects:1. The study of the full spectrum K-distribution model in the treatment of hightemperature gas’s non-gray properties. Based on the existence K-distribution model,establish the gas full spectrum K-distribution model by the use of the HITEMP database.2. The FSK model of the high temperature particles’ non-gray radiative properties.Separating the particle’s absorbing and scattering properties, establish the absorbing factorFSK model and the scattering factor FSK model, respectively. Set up the database andanalyzing its feasibility.3. Availability analyze the FSK model of the gas–particle mixture with thecombination of the discrete ordinates method. Give the calculation of different opetatingconditions of a single gas, mixed gas, pure absorption gas-particle mixture and absorbingand scattering gas-particle mixture’s radiative heat transfer. The results show that theresults of the full spectrum K-distribution model and the discrete ordinates method for theproblem of the gas-particle mixture non-gray properties meeting with the results of SNB model and LBL model. The FSK model greatly improves the computational efficiency...