A regressive model for dynamic instabilities during the condensation of R404A and R507 refrigerants. (October 2019)

• Record Type: Journal Article
• Authors: Kuczynski, Waldemar; Bohdal, Tadeusz; Meyer, Josua P.; Denis, Aleksander
• Is Part Of: International journal of heat and mass transfer. Volume 141(2019)
• Page Start: 1025
• Page End: 1035
• Publication Date: 2019-10
• Subjects: Condensation refrigerants -- Mini-channels -- Instability -- Regression function; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2019.06.095
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: Evolution and disappearance of condensation of R507A refrigerant in pipe mini-channels. Condensation process occurring in mini-channels. Comparison of the results of experimental studies with R404A obtained for R507A. Proposition of a regression function for the description of dynamic instability. Abstract: This paper presents the results of experimental research and mathematical modelling on the influence of dynamic instabilities on the condensation phase change of R507 refrigerant in tubular mini-channels. This agent is currently being utilised as a temporary substitute for R404A, with R448A intended as the target substitute. In addition to the results, this paper contains a dimensional analysis procedure based on the Π-Buckingham theorem that has allowed for the development of a regressive model for the velocities of the dynamic instabilities. The experimental part of this paper was conducted using tubular mini-channels with internal diameters of 1.44, 2.3, and 3.3 mm.