Simple Method for Spectral Evaluation of Radiant Energy Emitted from Far Infrared Heaters

It is necessary to know the spectral emissivity of a heater to ensure efficient heating. This paper proposes a useful method for spectral evaluation of radiation energy emitted from far infrared heaters. The measurement device consists of one radiometer and two band-pass filters. In order to confirm the experimental results, numerical simulations were also carried out with the spectral emissivity of the heaters and the respective spectral sensitivities of the radiometers. The results obtained by these methods show that the far infrared heater radiates high amounts of energy in the far infrared region even at high temperature. It means far infrared heaters can transmit power effectively to materials which exhibit high emissivity in the far infrared region. This method can classify a type of far remote infrared heaters with the near infrared/far infrared energy ratio. By using this data, the authors also proposed a simple identification method of spectral emissivity of far infrared heaters. This inverse method can obtain a rough value of the spectral emissivity of commercial heaters while maintaining the heating conditions. (C) 2012 Wiley Periodicals, Inc.