A NEW INSTRUMENT FOR RADIATION HEAT-FLUX MEASUREMENT - ANALYSIS AND PARAMETER SELECTION

In a number of combustion chambers, differentiation between radiation and convective heat transfer on the surface is a problem of substantia l interest. The hemispherical radiation heat Aux meter proposed by Afg an and Leontiev [1] and patented by Afgan, Carvalho, Martins and Leont iev [2] has potential to be used as an instrument with sufficient accu racy to measure the difference between hemispherical radiation heat fl ux and convective heat flux in the respective environments. The hemisp herical radiation flux meter is numerically analyzed with the aim of d efining the optimal design parameters to be used for experimental veri fication. With a proper selection of the design parameters correspondi ng to the conditions encountered in the boiler furnace, it will be pos sible to measure with the same instrument the radiation heat flux and convective heat flux. Particular attention was focused on the discussi on of the respective parameters of the Aux meter in order to meet corr esponding requirements in different environments. Attention was focuse d on the effects of differences in main mass flow rate and blow-off ga s mass Row rate, heat conductivity of the holder and porous filament a nd the difference in temperature between solid structure and fluid flo w in the filament. For the selected parameters of the main flow and ra diation heat flux range, the radiation heat flux meter was designed.