The present paper reports the heat transfer coefficients measured during flow boiling of HFC-32 and HFC-134a in a 0.96 mm diameter single circular channel. The test runs have been performed during vaporization at around 30°C saturation temperature, correspondent to 19.3 bar for R32 and 7.7 bar for R134a. As a peculiar characteristic of the present technique, the heat transfer coefficient is not measured by imposing the heat flux; instead, the boiling process is governed by controlling the inlet temperature of the heating secondary fluid. The quality of the inner surface of the test tube has been measured to check the influence of surface roughness on the heat transfer coefficient. The flow boiling data taken in the present test section is presented and discussed, with particular regard to the effect of heat flux, mass velocity, vapor quality and fluid properties.
- Nanotechnology Institute
Flow Boiling of Refrigerants Inside a Single Circular Minichannel
- Views Icon Views
- Share Icon Share
- Search Site
Bortolin, S, Cavallini, A, Del Col, D, Matkovic, M, & Rossetto, L. "Flow Boiling of Refrigerants Inside a Single Circular Minichannel." Proceedings of the ASME 2008 6th International Conference on Nanochannels, Microchannels, and Minichannels. ASME 2008 6th International Conference on Nanochannels, Microchannels, and Minichannels. Darmstadt, Germany. June 23–25, 2008. pp. 649-656. ASME. https://doi.org/10.1115/ICNMM2008-62270
Download citation file: