Abstract

This study investigates the evaporation heat transfer coefficient and two-phase frictional pressure drop of refrigerant mixture R1234ze(E)/R32 at various R1234ze(E) composition ratios in a brazed plate heat exchanger. The heat transfer coefficient of R1234ze(E)/R32 shows a concave curve as a function of composition ratio owing to the temperature glide of the mixture, whereas the two-phase frictional pressure drop increases exponentially with respect to the composition ratio. In addition, the averaged evaporation heat transfer characteristics of R32, R1234ze(E)/R32 (85%/15%), and R1234ze(E) are compared by considering the European Union (EU) regulations for global warming potential (GWP). For regulation phase A (GWP > 750), R32 exhibits the best heat transfer performance, whereas for regulation phase B (GWP > 150), R1234ze(E) shows a favorable averaged heat transfer coefficient compared to R410A and R134a. Finally, based on the measured data, correlations for the Nusselt number and two-phase friction factor for R1234ze(E)/R32 are derived as a function of composition ratio using a nonlinear interpolation method with the pre-developed correlations for pure R1234ze(E) and R32.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.