The curing of powder coatings using gaseous infrared heaters: An analytical model to assess the process thermal efficiency

This experimental investigation is structured to determine the efficiency o f energy transfer between a gaseous infrared burner and a powder coated sur face being cured. The results from the experimental burner tests are interp reted using a Monte Carte based numerical simulation. This simulation incor porates both an Edwards' exponential wide band model for the spectrally sel ective energy absorption and emission in the flue gas, and test measurement s for the powders' spectral absorption characteristics. The results from th e simulation show that efficiency of the energy transfer from the natural g as stream to the powdered surface ranges between 25 % and 30 %, when the bu rner is operating at stoichiometric conditions. The highest efficiency was obtained for the darkest coloured powder. The energy efficiency was also fo und to increase with burner temperature, However, the quality of the cured surface tended to decrease if the temperature rise was significant. (C) 200 0 Editions scientifiques et medicales Elsevier SAS.