TRANSPIRATION COOLING WITH LIQUID METALS. PART II. THEORETICAL DETERMINATION OF OPTIMUM COOLING PARAMETERS NEAR STAGNATION REGIONS.
Abstract
Three cooling mechanisms associated with liquid metal transpiration near stagnation regions were investigated theoretically. The cooling mechanisms considered were boundary layer shielding, heat absorption by vaporization, and heat absorption within the matrix as coolant travels under the action of some pressure force to the hot surface. Optimum coolant flow rate necessary for complete vaporization of liquid coolant at the hot wall was derived from knowledge of these mechanisms. Lithium, tin, and copper were the metal coolants investigated, with gaseous helium being included for comparative purposes. Tungsten was the matrix material for all coolants. Results of this analysis demonstrate that each coolant's effectiveness depends on the magnitude of the heat flux. In general, low melting point is the desirable coolant property at low and intermediate heat fluxes, while low molecular weight and high heat of vaporization become the important properties at high heat fluxes. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1965
- Accession Number
- AD0623020
Entities
People
- William H. Thielbahr
Organizations
- Naval Air Weapons Station China Lake