Effects of Surface Conditions on Boiling Characteristics,

Abstract

A unified model relating surface variables to the nucleate pool boiling characteristics was developed. A simple vapor trapping mechanism was postulated and a geometrical model constructed for idealized conical cavities relating the effective radius for nucleation to cavity radius, cone angle and contact angle. This model for individual cavities was extended to the entire surface providing an expression for the cumulative site density in terms of geometrical parameters. A gas diffusion technique was developed to measure the effective radius for natural cavities and was used successfully to verify the nucleation criteria Delta T = 2(sigma)(T sub s)(V sub fg)/h(fg)rho. A transient heat conduction model was esxperimentally verified for water and organics at atmospheric pressure and was incorporated into a unified expression showing explicitly the role of surface geometry and contact angle. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1972
Accession Number
AD0762368

Entities

People

  • B. B. Mikic
  • J. J. Lorenz
  • W. M. Rohsenow

Organizations

  • Massachusetts Institute of Technology

Tags

DTIC Thesaurus Topics

  • Barometric Pressure
  • Diffusion
  • Geometry
  • Nucleation
  • Surface Properties

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Plasma Physics / Magnetohydrodynamics
  • Thermal Physics or Thermal Science.