TY - JOUR N2 - This paper presents the results of an experimental study and mathematical modeling of the effect of dynamic instabilities on the condensation phase transformation of the refrigerants homogeneous R134a and its replacement in the form of isomers R1234yf and R1234ze and R404A or R507 and R448A in pipe mini-channels. In the case of homogeneous chlorofluorocarbons (CFCs), it is the 1234 isomers that are envisioned as substitutes for the withdrawn ones with high ozone depletion potential and global warming potential. For zeotropic and azeotropic mixtures, for example, these are R507 or R448A. The paper presents a dimensional analysis procedure based on the Buckingham Π theorem to develop a regression velocity model of pressure dynamic instabilities. The experimental part of the work was carried out with the use of tubular mini-channels with internal diameter 1.40–3.3 mm. L1 - http://journals.pan.pl/Content/127284/PDF-MASTER/art07_int.pdf L2 - http://journals.pan.pl/Content/127284 PY - 2023 IS - No 1 EP - 137 DO - 10.24425/ather.2023.145880 KW - refrigerants KW - Condensation KW - Mini-channels A1 - Kuczyński, Waldemar PB - The Committee of Thermodynamics and Combustion of the Polish Academy of Sciences and The Institute of Fluid-Flow Machinery Polish Academy of Sciences VL - vol. 44 DA - 2023.05.26 T1 - Modeling the phenomena accompanying the condensation of environmentally friendly refrigerants in mini-channels SP - 121 UR - http://journals.pan.pl/dlibra/publication/edition/127284 T2 - Archives of Thermodynamics ER -