On the relation between shape and downward radiation of overhead radiant heaters

摘要

The paper aims on evaluating and assessing of the influence of a shape of overhead luminous infrared heater's burner on heat distribution to the ambient. These devices are mainly used for heating of industrial or other large space buildings. The contribution is based on comparison between the experimental results and created mathematical model. The latest experimental results show that the maximum of radiant intensity does not lay right below the radiant heater. Actually, there exists a ring of maximal values around heater's midpoint axis. Results prove that instead of reflectors' geometry, very complicated shape of gas luminous heater's burner plays the most significant role in radiant heat transfer from the luminous heater. It was evaluated that the position of the radiant intensity maximum is around 10 deg from the radiating surface's normal direction. All the findings can be summarized in conclusion that uniform distribution of radiant intensity required for thermal comfort of occupants can be maintained just by optimizing of the shape of radiant heater's burner. Besides this conclusion, it is also apparent that adding the reflector actually increases summary radiant heat flux to the desired zone and therefore radiant efficiency increases. It is also clear that varying the reflector shape, different improvement of the efficiency can be expected.