Thermoelectric cooling and heating of human body temperature

Abstract

The cooling and/or heating of human body temperature is of critical importance and interest in a myriad of applications, however, the use of thermoelectric cooling has made little impact in this area. Current solutions focus on the use of wearable materials that assist the natural temperature regulation of the human body, or the use of liquid cooling techniques reliant on refrigerant fluid or large quantities of dry ice, often used in astronaut spacesuits, worn by surgeons during long surgical procedures, firefighters, military personnel, and motor racing drivers. The motivation for this work is to investigate the feasibility of using thermoelectricity to achieve the cooling process, replacing the existing use of refrigerant fluid and associated compressor and refrigeration components or the use of large quantities of dry ice to create chilled or cooled water. A thermoelectric cooling/heating prototype system has been designed and tested, and successfully demonstrates the temperature of circulating water within small tubes incorporated into a person’s vest undergarment can be used to regulate body temperature. The system briefly comprises: a small reservoir tank of water; a thermoelectric module, heatsink and electronic fan; a small electronic water pump; a proportional, integral, and derivative (PID) controller; interconnecting tubing to carry the circulating water; and a vest undergarment that is worn by the user to help regulate their body temperature. Results presented demonstrate the thermoelectric module successfully cools or heats the water circulating around the vest undergarment, which when worn by a user can be used to lower or increase their external body temperature and improve their temperature comfort levels. The thermoelectric cooling/heating system has several advantages over existing solutions including; a significant decrease in size and weight; system cost; accurate temperature control; ability to provide cooling or heating under user control; no moving parts within the thermoelectric module contributing to high reliability and reduced maintenance requirements; quiet in operation; the elimination of dry ice in the cooling process; and no use of refrigerate fluid or other harmful chemicals. Further work will optimize the design, scale the system to achieve specific cooling/heating targets, and demonstrate the effectiveness of the system in improving a user’s temperature comfort levels.