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Show 10 Based on the numerical results of the simulations of the LIF the following conclusions can be drawn: 1. The choice of the band models is very important in calculating the temperature distribution in the load. From the viewpoint of uncertainties in the radiation properties, two-band model provides a reasonable compromise and yields good estimate of the temperature distribution in the load. 2. The thermophysical properties of the load have a great effect on the load surface temperature, furnace efficiency and the temperature deviation in the load. High emissivity of the load can increase the load surface temperature, enhance the furnace efficiency and increase the temperature deviation in the load. However, a comparison of iron and aluminum as load materials reveals that the high thermal conductivity is more effective in improving the thermal performance of the furnace. 3. Smaller radiant heater panels but having the same total surface area as larger panels can provide more uniform temperature distribution in the load. 4. Stirring of the gas in the furnace enclosure increases the temperature uniformity of the load. 5. Test data on a low inertia furnace with a simple load geometry are needed to compare the model predictions with measurements for the purpose of validating and, if needed, improving the model. NOMENCLATURE c specific heat, J kg"1 K"1 Cp specific heat of gas filling the furnace enclosure, J kg"1 K"1 Fj.j configuration factor between i-th and j-th surfaces G incident radiation flux, W / m 2 h convective heat transfer coefficient, W m ' 2 K'1 h effective heat transfer coefficient accounting for radiative and convective heat transfer between furnace wall and ambient, W m " 2 K H furnace enclosure height, m J surface radiosity, Wm"2 L furnace enclosure length, m n normal direction or number of spectral bands N total number of isothermal surface zones q heat flux, W m " 2 T absolute temperature, K t time, s V velocity, ms"1 W furnace enclosure width, m x,y,z coordinates Greek Symbols a absorptivity e emissivity r| furnace efficiency p density, kg m"3 a Stefan-Boltzmann constant, W m " * K"1 Subscripts b refers to black body c refers to convection g refers to furnace gas L refers to load o refers to outer r refers to radiation w refers to wall |