Volume 51

Transient Behavior of a Two-phase-closed Geothermal Thermosyphon Tareen, M. S. K., Badache, M., & Sasmito, A. P.

Abstract

This study investigates the transient response of a novel CO2 geothermal thermosyphon (GT) integrated with heat recovery ventilators (HRVs), used to reduce the heating load of buildings in northern regions. Particularly, the transient response of the GT-HRV test bench is presented in this paper, characterizing the integrated system response under various test conditions in terms of time constant (T), heat transfer rate, and average evaporator temperature (Tev). Key experimental parameters include the GT filling ratio, coolant temperature, and coolant flow rate. The results indicate that a distinct T can be associated with each location of GT in fixed experimental conditions ranging from 417 seconds to 3762 seconds for coolant flow rate and inlet temperature set points of 0.05, 0.1, 0.15 and 0.2 l/s, and -9, -5 and -1 C.

Keywords Heat recovery ventilators, Geothermal thermosyphon, renewable energy, geothermal energy, energy systems, climate change