Publications Repository - Gdańsk University of Technology

In the paper are presented the results of follow on studies from [1]–[3] using authors own model to predict heat transfer coefficient during flow boiling. The model has been tested against a large selection of experimental data collected from various researchers to investigate the sensitivity of the in-house developed model. The collected experimental data came from various studies from literature and were conducted for the full range of quality variation and a wide range of mass velocity and saturation temperatures. In the work are presented the results of calculations obtained using the in-house developed semi empirical model on selected experimental flow boiling data of the following refrigerants: R134a, R1234yf, R600a, R290, NH 3 , CO 2 , R236fa, R245fa, R152a and HFE7000. In the case of the fluid HFE7000 authors own unpublished experimental results have also been presented. In the present study the particular attention was focused on the influence of reduced pressure on the predictions of the theoretical model. The results of calculations were to test the sensitivity of the flow boiling model with respect to selection of the appropriate two-phase flow multiplier, which is one of the distinctive elements of the in-house model. Four two-phase flow multiplier models were used for this purpose, i.e. due to Müller-Steinhagen and Heck and its in-house modification for applicability to minichannels, Friedel and Tran. The main purpose of this paper however is to show the effect of the reduced pressure on the predictions of heat transfer during flow boiling in minichannels.

Authors

• prof. dr hab. inż. Dariusz Mikielewicz link open in new tab ,
• dr inż. Blanka Jakubowska link open in new tab