METHOD OF AND DEVICE FOR DETERMINING HEAT CONDUCTANCE OF SOLID MATERIALS Russian patent published in 1994 - IPC

FIELD: thermal measurements. SUBSTANCE: heaters create heat fluxes in analyzed and standard specimens and equal temperatures are maintained within them. During measurements constant-magnitude current is supplied to standard specimen heater. Current through analyzed material heater is increased or decreased depending on polarity of signal coming from bridge circuit that functions to measure temperature difference between heaters. This process goes on until signal value drops below threshold limit and is maintained so within time interval τ = h²/8χ, where h is characteristic size of specimen; c is thermal conductance of specimen. To ensure more accurate measurement results, device implementing this method is provided with comparison, regulation, recording, standard parameter setting units. Prior to taking measurements, analyzed and standard specimens are placed in measuring cell made of high-conductivity material. Heaters are installed on heat-insulating plates with flexible-material posts placed inbetween. Heaters are joined together by means of rubber sleeve. EFFECT: improved measurement accuracy. 3 cl, 1 dwg