Theoretical, experimental and numerical study of infrared radiation heat transfer in a drying furnace

This paper aims at the study of thermal radiation heat transfer in a drying furnace considering: heating surfaces, reflector shield and load material for three power levels: 27 kW, 41 kW and 55 kW. An algorithm was developed to calculate the energy rate transferred to the load by radiation, the heat losses, and the radiation efficiency. The algorithm was validated with an experimental setup. The thermal radiation measurement methodology called “simplified view factor method for radiative heat flux measurement” was modified to measure thermal radiation in rectangular areas by the introduction of a correction factor. This factor had a good agreement with the numerical simulations. Also, it was possible to carry out the thermal characterization of an infrared radiation drying furnace at low temperature. It was determined that these kind of furnaces have a radiation efficiency of not more than 32%. Furthermore, it was found theoretically and experimentally that the radiation efficiency is almost constant for all power levels. •A methodology for thermal radiation measurements on furnaces.•Correction factor for rectangular surfaces measures.•Furnaces have a radiation efficiency not more than 32%.•Radiation efficiency is almost constant for all power levels.