METHOD OF DETERMINATION OF HEAT CAPACITY AND RELAXATION TIME OF TEMPERATURE FIELD OF CAPILLARY-POROUS MATERIALS

摘要

FIELD: technical physical, thermophysical measurements. SUBSTANCE: in compliance with proposed method of determination of heat capacity and relaxation time of temperature field in capillary-porous materials surface of examined sample is exposed to action of flat heat source of minimal power which will result in emergence of excess temperature in point located on opposite side of sample in the form of plate heat-insulated from environment. Excess temperature and rate of its change are measured in tested point at three time moment specified in advance and sought-for heat capacity and relaxation time are found in first approximation. Examined body is exposed to power which value exceeds initial magnitude of power by value set beforehand, excess temperature and rate of its change are fixed at following three time moment in tested point and sought-for thermophysical characteristics are determined in second approximation. Then type and power of thermal action are determined by minimal of energy consumption with allowance for time of experiment as well as excess temperature and rate of its change in tested point when system is brought to preset thermal mode. Examined body is exposed to action of this power in the course of specified time interval and after this excess temperature and rate of its change in tested point at three specified time moments are measured. Finally sought-for heat capacity and relaxation time of temperature field are determined. EFFECT: enhanced authenticity of method. 1 dwg, 1 tbl