The invention relates to the field of thermophysical property measurement, and provides an in-situ measurement method and
system for a density Virie coefficient and a characteristic
thermodynamic temperature thereof, and the measurement method comprises the steps: S1, carrying out the in-situ measurement of the density Virie coefficient and the
thermodynamic temperature: S10, carrying out the
vacuum pumping of the measurement
system, measuring the resonant frequency of a
resonator in a
vacuum state at a preset temperature, introducing a gas to be measured, and measuring the resonant frequency of the
resonator under a preset pressure and a preset temperature; s11, according to the resonant frequency measurement result, calculating the experimental
refractive index of the gas, and calculating the theoretical
refractive index of the gas through a Virie state equation and a
dielectric Virie theory; s12, iteratively solving to obtain experimental values Bexp of the
thermodynamic temperature T and the density Virie coefficient; and S2, carrying out in-situ fitting or in-situ iteration on the characteristic temperature. Aiming at the problems of complex flow, poor measurement accuracy and the like of an existing measurement method, high-precision in-situ measurement of the gas density Virie coefficient and the characteristic temperature of the gas density Virie coefficient is realized.