Reversible Heat Exchange in the Nozzle with Water–Ice Phase Transition in Filtration of Air

Results of experimental study of reversible heat exchange with water–ice phase transition in filtering the airflow through a tube heat exchanger are presented. The heat exchanger is made of thin-walled plastic tubes (3 and 5 mm in diameter) filled with water and sealed at both ends. The heat exchanger was tested in a laboratory setup with a Ranque tube applied to create a flow of cold air. The heat exchanger operation was investigated in steady-state and various reversible modes. Themeasurements showed the possibility of substantially increasing the time between switching the direction of airflow with maintaining a high coefficient of heat regeneration. The results can be used in the development of regenerative heat and mass transfer devices, including VENTIREG systems of ventilation emission heat regeneration.