Performance optimization of a miniature Joule–Thomson cryocooler using numerical model

•We numerically simulated the Hampson-type heat exchanger for J–T cryocooler.•A correction factor is used to find realistic heat exchange area for performance prediction.•Performance optimization of the J–T cryocooler is carried out.•The parametric study is carried out to find the optimum performance of the J–T cryocooler. The performance of a miniature Joule–Thomson cryocooler depends on the effectiveness of the heat exchanger. The heat exchanger used in such cryocooler is Hampson-type recuperative heat exchanger. The design of the efficient heat exchanger is crucial for the optimum performance of the cryocooler. In the present work, the heat exchanger is numerically simulated for the steady state conditions and the results are validated against the experimental data available from the literature. The area correction factor is identified for the calculation of effective heat transfer area which takes into account the effect of helical geometry. In order to get an optimum performance of the cryocoolers, operating parameters like mass flow rate, pressure and design parameters like heat exchanger length, helical diameter of coil, fin dimensions, fin density have to be identified. The present work systematically addresses this aspect of design for miniature J–T cryocooler.