HUMAN THERMOREGULATORY RESPONSE TO INFRARED RADIANT HEATING
This report discusses the workings of infrared radiant heating and investigates its applicability for indoor comfort applications. The fundamental concepts of radiant heat transfer, the human thermoregulatory system, and human thermal comfort are introduced. The current applications of electric infrared radiant heating are discussed, and it is compared with conventional convective heating methods. Experiments are conducted to obtain temperature and heat flux distribution characteristics for two ceramic element heaters.
It is found that for both heaters the temperature and heat flux distributions are symmetric about symmetric sections of heater shape and vary most significantly within 0.5m of the heat source, after which distributions become more uniform. The trends between temperature and heat flux distribution are found to be similar for each heater, and the most appropriate placement of each heater for comfort applications is discussed. Further experiments investigate the human thermoregulatory response to infrared heating.
A series of tests are carried out on a group off four subjects involving the application of infrared heat to the face or hand area whilst core temperature, skin temperature, and heat flux measurements are recorded. Similar testing is carried out using convective heating, and the two heating types are compared. Differences in trend between infrared and convective heating are identified, and it is also found that human thermoregulatory response differs between individuals tested.
It is shown that the thermoregulatory system has the ability to effectively redistribute heat from an area directly heated by an IR source to other areas of the body so that heat may be lost from the surface of the skin and core temperature maintained at an appropriate level. In most cases the hand is seen to be the primary area to which heat is transferred for dissipation to the surroundings.