EHD enhancement of pool and in-tube boiling of alternate refrigerants. Final report, 15 January 1993--15 June 1993.

摘要

The Electrohydrodynamic (EHD) is an active heat transfer augmentation technique which utilizes the effect of secondary motions generated through the application of an electrostatic potential to a dielectric fluid. Net result is better momentum and heat transfer between the fluid and the heat transfer wall through destabilization of the thermal boundary layer and better mixing of the fluid adjacent to the heat transfer surface. EHD enhancement of refrigerant/refrigerant oil mixtures heat transfer using the Electrohydrodynamic (EHD) technique is the subject of a three-year experimental investigation in a project funded by the US Department of Energy, effective June 1, 1993. For the interim period between November 1992 and June 1993 when the DOE funds became available, the Air-Conditioning and Refrigeration Technology Institute (ARTI) provided partial funding for our EHD research program with the aim of accomplishing three major tasks: (1) conduct a comprehensive search of the literature on EHD-enhanced, in-tube and external boiling heat transfer enhancement of alternate refrigerants; (2) Design, fabricate, and instrument an in-tube, EHD-enhanced boiling/condensation test rig and perform preliminary testing of the setup; (3) conduct experiments and document new findings on EHD-enhanced external boiling of alternate refrigerants/refrigerant mixtures in an existing pool boiling test rig apparatus. Description of Tasks performed are described and results are discussed.