Research On Flow And Heat Transfer Mechanics At The Interaction Of Conduction,Convection And Radiation On Gas Turbine Hot Component

With the continuing increase of the turbine inlet temperature, cooling technologyhas been put into wide range of applications as a necessary means. Since the radiativeheat transfer should not be ignored under the high temperature circumstances, it isessential to consider radiative effect when doing research about high temperaturecooling system. This thesis firstly describes the set up of conjugate heat transferexperimental test rig with high temperature flat plate cooling system and then studiesthe comprehensive effect of surface convection, radiation and conduction heat transferwith film cooling, finally analyses multiple parameters effect on film cooling system.With the experimental data of high temperature film cooling conjugate heattransfer showing that the radiative heat transfer effect should not be ignored, the DOmodel is introduced to solve the radiation transport equation, accomplishing severalconjugate heat transfer numerical simulations contrasting to the experimental test cases.Detailed effect of conjugate and adiabatic cases on the cooling effectiveness is studiedand the interaction of film cooling and heat transfer mode is analysed. Computationalresults show that the velocity field is not affected by the internal cooling convection andradiative heat transfer, but the conjugate and radiative effect play an important part inthe temperature field. When considering the wall as insulated and radiative, the wallwill deliver heat to the cooling film due to convection. To exclude the impact of theinternal cooling, a new film cooling effectiveness is defined, combining with the heatflux ratio is used to analyze the film cooling under conjugate conditions.Based on the conjugate heat transfer calculations considering radiative effect, thisthesis inspects multiple experimental parameters variations on the temperature flatplate distribution including the temperature of sidewall temperature, mass flow ratioand inlet radiation intensity.Finally the thesis proposed a method to reversely calculatethe inlet radiation intensity combining the experimental data and numerical simulationwhich show quite good predictive ability.