There is a gap of knowledge on flow boiling at high saturation temperatures and higher values of reduced pressure. Thus far, the in-house developed semi-empirical model for flow boiling and flow condensation showed a satisfactory accuracy for calculations for various refrigeration fluids for a wide scope of reduced pressures. This study presents results of calculations of heat transfer coefficient of perspective refrigeration fluids, such as R152a, R32, R245fa, propane and isobutane. Computations were carried out to validate the generalized theoretical in-house model. Study was performed for both conventional and minichannel tubes for a full range of vapour quality. The vast part of the database consists of experiments carried out for low saturation temperature, however in case of R245fa the collected data includes medium and high saturation temperatures. The theoretical results shows a good agreement with experimental data especially for low saturation temperature cases. Most unfavorable outcomes were gained for R245fa. Inconsistency of these results show that more attention should be given to the influence of higher values of reduced pressure on heat transfer predictions.
Authors
Additional information
- Category
- Publikacja monograficzna
- Type
- rozdział, artykuł w książce - dziele zbiorowym /podręczniku o zasięgu krajowym
- Language
- polski
- Publication year
- 2020
