THERMAL BIONICS. ACTIVE THERMAL PROTECTION OF LIVING ORGANISMS AND POSSIBILITY OF ITS APPLICATION IN ENGINEERING

Abstract

Warm-blooded organisms have an effective system for maintaining body temperature. To clarify the characteristics of thermoregulation of living organisms, a mathematical model of thermal exchange of living tissue with the environment is presented. Using reference data of the average skin temperature and the volume of blood pumped by the human heart, calibration of the mathematical model is developed. It is shown that by regulating the intensity of blood flow in the skin and subcutaneous tissues, organisms can alter the apparent thermal tissue conductivity to, at least, two orders of magnitude. Based on the obtained quantitative results, the phenomenon of walking on hot coals is explained.  Application prospects of active thermal protection in cryogenic and aerospace engineering are analyzed. Estimated calculations show that the ordered heat insulated structure, which imitates a living tissue, has an equivalent thermal conductivity of 0,014 W/(mK) at a rate of nitrogen circulating therein of 2,6 mm/s. In this example, consumption of energy required to maintain the gas circulation is of the order of 1 milliwatt per square meter of a thermally insulated surface.