Performance evaluation of heat exchanger for mixed refrigerant J–T cryocooler

Numerical analysis of the two-phase heat transfer in the heat exchanger of a mixed refrigerant Joule–Thomson cryocooler

“…This explains the reason of these differences. A similar observation was reported by Ardhapurkar et al [14], in their calculation (theoretical and experimental) of overall heat transfer coefficients with modified Granryd correlation on the boiling side and Cavallini and Zecchin [17] correlation for condensation. The deviations reported by them between the experimental and theoretical values of heat transfer coefficients were in the range of 3-18.7%.…”

“…Based on the conclusions drawn by Ardhapurkar et al [14], the correlation of Cavallini and Zecchin [17] is employed for calculating the condensation heat transfer coefficients. Cavallini and Zecchin [17] correlation for condensation is a modified form of the well-known Dittus-Boelter correlation.…”

“…They modified the Granryd correlation[13] for higher mass fluxes. Ardhapurkar et al[14] carried out a performance analysis of the recuperative heat exchanger for an MR J-T cryocooler. Modified Granryd correlation is used for boiling while the correlations of Shah[15], Dobson-Chato[16], and Cavallini-Zecchin[17] are employed for condensation.…”

Prediction of two-phase pressure drop in heat exchanger for mixed refrigerant Joule-Thomson cryocooler

“…The experimental two-phase frictional pressure drop data are compared with 15 existing correlations which are used for flows through both macro and mini/micro channels. The average absolute deviations (AAD) for the predicted results are calculated using equation (6), in order to find applicability of the correlations. 1 100…”

“…These studies are mainly related to the optimization of mixtures used and the overall performance of the refrigeration systems. However, little work [5][6][7] is done on the performance analysis of the recuperative heat exchanger used in the MR J-T cryocooler, even though it plays a crucial role in its efficient operation. This is mainly due to the lack of the experimental data available, related to flow boiling/condensation heat transfer and pressure drop of mixed refrigerants at cryogenic temperatures.…”