Heat-Transfer Studies of Dropwise Condensation and Thin-Film Evaporation

Abstract

Experiments were conducted to investigate heat transfer rates from water-film evaporation and dropwise condensation. Dropwise condensation was induced by coating the external surface of the heat-exchanger tubes with a polytetrafluoro ethylene polymer, and film evaporation was obtained by allowing water to fall in a thin film around the surface of the tube. The effect of tube length and feed flow on the over-all heat-transfer coefficient was also investigated. The over-all heat-transfer coefficients obtained from the dropwise condensation experiments were considerably greater than those obtained from the film-type condensation experiments conducted to obtain comparison data. Over-all heat transfer coefficients as high as 4000 Btu/sq ft/F/hr were obtained from the dropwise condensa tion experiments as compared to values of about 700 Btu/sq ft/F/hr that were obtained from the film-type condensation. The results of thin film evaporation on the intended surface of the tube were inconclusive.

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Document Details

Document Type
Technical Report
Publication Date
Jun 30, 1963
Accession Number
AD0410566

Entities

People

  • C. Saturnino

Organizations

  • Naval Facilities Engineering Service Center

Tags

Communities of Interest

  • Advanced Electronics
  • Biomedical
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Chemistry
  • Civil Engineering
  • Compressors
  • Design Criteria
  • Engineering
  • Engineers
  • Films
  • Heat Energy
  • Heat Transfer
  • Heat Transfer Coefficients
  • Marine Corps
  • Materials
  • Navy
  • Thickness
  • Thin Films
  • Training

Fields of Study

  • Chemistry

Readers

  • Combustion and Flow Dynamics.