Experimental Evaluation of Air Cryotherapy Unit Control System

The article focuses on the development and testing of an experimental local air cryotherapy unit. The device uses a single-stage vapor compression cycle with refrigerant R404A to cool air to temperatures ranging from <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$-30^{\circ}\mathrm{C}$</tex> to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$-35^{\circ}\mathrm{C}$</tex>. The designed control system ensures the stability of operational parameters and allows airflow regulation based on nozzle diameter and target area. The results of the experimental unit's operation in various modes are presented. The findings confirm the effectiveness of the control system for conducting regulated cryotherapy procedures and the applicability of the experimental unit for studying optimal cooling modes.