Numerical and experimental investigations on two-phase flow of liquid nitrogen in a flexible transfer line

Transfer of cryogenic fluids is a daily occurrence in laboratories and industries for various end applications. Vacuum or super insulated transfer lines are generally used to transfer cryogens to minimize the evaporation due to heat transfer. Because of the heat transfer and the nature of flow, most of the time two-phase flow occurs during the transfer of cryogens. It is necessary to estimate the amount of cryogen being evaporated and the quality of the flow in the transfer process. This paper deals with the numerical and experimental investigations on the two-phase flow behaviour of liquid nitrogen transfer through the developed flexible transfer line. Diode based liquid level sensors have been developed to measure the void fraction of the two-phase flow. The numerical and the experimental results are in good agreement with each other. Pressure drop and cool-down data of the transfer process is also presented in the paper.