Energy requirements for nitrogen cooling systems of WBC units

Abstract

D. Sc. A. Yu. BARANOV1, O. A. FILATOVA, A. V. VASILENOK, A. V. SAFONOV, E. V. SOKOLOVA 1abaranov@corp.ifmo.ru ITMO University Whole-body cryotherapy (WBC) technique is based on supercooling patient’s body to stimulate skin cold receptors at the depth of 0.15 мм form skin surface forming signal of maximum intensity at the temperature of –2 оС. Heat removal by gas with the temperature of not more than –130 оС allows localizing body supercooling zone at the depth of receptors. The research is made to estimate maximum intensity of heat removal and necessary power consumption. It allows determining requirements for power supply of WBC units that is crucial for efficiency and safety of WBC. The research is carried out by the mathematical models of WBC object (human body surface) and a unit of volume for WBC zone (patient’s cabin). Implementation of WBC technique is shown to require removing 3.8 kW of heat from patient’s body surface. Taking into account total refrigerating capacity the cryostatting system for single-seated WBC cabin has to remove as less as 6.4 kW of heat form the temperature level of –130 оС. Therefore, a refrigerator of 47 kW power or nitrogen cooling system with refrigerating medium consumption of 0.025 kg/s or 4.45 kg per procedure is necessary. The use of nitrogen cooling for WBC zone results is compact and mobile single-seated WBC units. Owing to high competitive advantages single-seated units for WBC are widely used in the world, they being used in Russian clinical practice for more than 20 years.