Trotsenko A. Investigation of thermodynamic efficiency of low temperature system.

Dependence between optimal parameters determined at various criteria are considered. The formalization for thermodynamic model of low temperature system is suggested. The general expression for determination of independent variable number in thermodynamic calculations and optimization was obtained. The evaluation of some indefinite forms at the critical point of pure substances is carried out. This gives the possibility to discover new sets of critical conditions. Created general algorithms for solutions of typical thermodynamic tasks are presented. The analytical investigations of throttle and expander cycles at various criteria are carried out. The method of prediction and calculation of azeotropic behaviour without performing mixture vapour - liquid equilibrium calculations is presented. The prediction results for binary azeotropic working substance of microcryogenic systems for nitrogen temperature level are shown.