HUMAN THERMOREGULATORY RESPONSE TO INFRARED HEATING
This study is the result of a thesis by the author of this article at the Department of Mechanical and Manufacturing Engineering at Trinity College Dublin, University of Dublin, Ireland. The study discusses the workings of electric infrared heating and investigates its applicability for indoor comfort applications. The important topics in this regard are the following:
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. A summary of that topic can be found in the article radiant power measurements for electric infrared heaters – part 5.
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.
It is shown that the thermoregulatory system has the ability to effectively redistribute heat from an area directly heated by an infrared heat 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.
To download the study, please click here.
Michelle Tannam, BAI