Heat Transfer Evaluation of HFC-236fa in Condensation and Evaporation
Abstract
The report gives results of an evaluation of the shell-side heat transfer performance of hydrofluorocarbon (HFC)-236fa, which is considered to be a potential substitute for chlorofluorocarbon (CFC)-114 in Navy shipboard chillers, for both conventional finned (1024- and 1575-fpm (fins-per-meter)) tubes and high performance enhanced (Turbo-CII, -B, and -BII) tubes. Condensation of oil-free HFC-236fa was conducted on 1024- and 1575-fpm, and Turbo-CII tubes. Pool boiling on four tube types (1024- and 1575-fpm, and Turbo-B and -BII) was tested not only for pure HFC-236fa but also for HFC-236fa mixed with 1 and 3% lubricant by weight. The polyolester lubricant used has a viscosity of 340 SSU at 37.8 deg C (100 deg F) and the trade name of Castrol Icematic SW-68. The above tubes, which have nominal outside diameters of 19.1 mm (3/4-in.), were evaluated at a saturation temperature of 40 deg C for condensation and 2 deg C for pool boiling over the heat flux range of 15 to 40 kW/sq m. Heat transfer was improved for HFC-236fa by using the high performance enhanced tubes. Specifically, the Turbo-CII tube performed better than the two conventional finned tubes in the condensation testing, while the performance of the Turbo-B and -BII tubes was superior to the two conventional finned tubes in the pool boiling testing.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1998
- Accession Number
- ADA364041
Entities
People
- M. B. Pate
- S. M. Tzuoo
Organizations
- Iowa State University