Low GWP refrigerants condensation inside a 2.4 mm ID microfin tube. (February 2018)

• Record Type: Journal Article
• Authors: Diani, Andrea; Campanale, Manuela; Cavallini, Alberto; Rossetto, Luisa
• Is Part Of: International journal of refrigeration. Volume 86(2018)
• Page Start: 312
• Page End: 321
• Publication Date: 2018-02
• Subjects: Condensation -- R1234yf -- R1234ze(E) -- R134a -- Microfin tube -- Heat transfer coefficient -- Pressure drop; Condensation -- R1234yf -- R1234ze(E) -- R134a -- Tube à micro-ailettes -- Coefficient de transfert de chaleur -- Chute de pression; Refrigeration and refrigerating machinery -- Periodicals; 621.56
• DOI: 10.1016/j.ijrefrig.2017.11.011
• Languages: English
• ISSNs: 0140-7007

Abstract

Highlights: Condensation heat transfer is studied inside a 2.4 mm ID mini microfin tube. Heat transfer coefficients and frictional pressure drops are obtained from the experimental measurements. Experimental heat transfer coefficients and frictional pressure drops are compared against values predicted by empirical correlations. Abstract: This paper explores the possible use of R1234yf and R1234ze(E) during condensation inside a microfin tube with an inner diameter at the fin tip of 2.4 mm as replacement of R134a. Having thermodynamic properties close to those of R134a, R1234yf and R1234ze(E) are some of its possible replacements for air conditioning and refrigeration systems. Experimental tests were carried out for mass velocities from 300 to 1000 kg m −2 s −1, vapor qualities from 0.95 to 0.2, at saturation temperatures of 30 °C and 40 °C. From the experimental measurements, it has been possible to calculate the heat transfer coefficient and to measure the frictional pressure drop. Globally speaking, R1234ze(E) shows heat transfer coefficients similar to those of R134a, whereas R1234yf shows slightly lower values. R1234ze(E) frictional pressure drops are some 30% higher than those of R134a, whereas R1234yf shows values similar to R134a. The experimental results of heat transfer coefficient and frictional pressure drop were also compared against values predicted by empirical correlations.