Irradiance Uniformity of a New Gas-Fired Directional Radiant Heater

A gas-fired directional radiant heater is proposed, and the irradiation characteristics were studied numerically. The heater is composed of a bundle of tubes set in front of a flat burner. The Monte-Carlo method is used to calculate the irradiation profiles on the surface of an object in front of the heater. The influence of the related parameters on the irradiation intensity and uniformity along the surface of the object are analyzed. The length-to-radius ratio of the tube bundle, the arrangement (aligned/staggered), and the distance between the burner and the object surface were the parameters in the analyses. The results show that, when a tube bundle is set in front of a conventional flat burner, the heat flux on the surface of an object facing the burner is almost uniform and the intensity is nearly independent of the distance between the surface and the burner.