Experimental research on the performance of a refrigerant generating bubble pump based on a diffusion generation process with H2O[sbnd]HCOOK-R134a

Abstract

A closed experimental system has been built to explore the performance of refrigerant generating bubble pump (used in diffusion absorption heat transformer), in which the refrigerant generation is based on a diffusion generation process and the absorbent solution is lifted by vapor mixture of diffusion gas and refrigerant. In experiments, R134a, H2O and HCOOK solution were employed as diffusion gas, refrigerant and absorbent for refrigerant, respectively. The influences of concentrations (the mass fraction of HCOOK), system pressures, motive heads, generating temperatures and diffusion gas flow rates on the refrigerant generating and solution pumping performance were investigated. The refrigerant flow rate was used to evaluate the refrigerant generating performance, while the solution flow rate and pumping ratio were used to evaluate the solution pumping performance. The experimental results showed that: (1) the increase of generating temperature and diffusion gas flow rate or the decrease of concentration and system pressure led to the increase of refrigerant flow rate; (2) the solution flow rate and pumping ratio were remarkably impacted by the motive head and diffusion gas flow rate; (3) the solution flow rate and pumping ratio increased with the increase of motive head or the decrease of diffusion gas flow rate. The results obtained in the paper will helpful to the design and optimization of the refrigerant generating bubble pump in the diffusion absorption heat transformer.