Bubbly boiling of environment-friendly refrigerating media

✍ Scribed by Tadeusz Bohdal

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 407 KB
• Volume: 21
• Category: Article
• ISSN: 0142-727X
• DOI: 10.1016/s0142-727x(00)00026-6

✦ Synopsis

The paper describes results of investigations of heat transfer and pressure drop during bubbly boiling of new environmentfriendly refrigerating media. Taking advantage of the experimental results, an analytical model of heat transfer and pressure drop is worked out. This continuum model draws on conservation equations for energy, momentum and mass of the two-phase onecomponent (liquid±vapour) mixture. In the light of engineering applications, a one-dimensional model is used, where physical quantities are cross-section averaged. Numerical calculations performed with the aid of an experiment-based correlation allow us to obtain the continuous distribution, along the channel, of quantities that characterise the process of bubbly boiling. The comparison of computational results and experimental data, own and from other authors, shows that the proposed method of determination of heat transfer coecients and pressure drop can be applied to a number of refrigerating media in a wide range of heat and ¯ow parameters, assuring accuracy to AE20%. Therefore, the method can be serviceable in the design of heat exchangers for refrigeration units as well as complete refrigeration units.