Accession Number:

ADA234288

Title:

Liquid Film Cooling in Rocket Engines

Descriptive Note:

Final rept. Jun 1987-Dec 1989

Corporate Author:

MOREHOUSE COLL ATLANTA GA

Personal Author(s):

Report Date:

1991-03-01

Pagination or Media Count:

72.0

Abstract:

A one-dimensional analytical model of liquid film cooling in rocket engine combustion chambers is developed and compared with existing data. The vapor generated at the liquid interface greatly decreases the convective heat flux and is treated as a transition process. The radiant heat is absorbed at the walls and transmitted to the liquid film by boiling, which can lead to burnout of the film. Downstream of the liquid film, the vapor provides continued thermal protection to the wall and is treated as a gaseous film cooling process. A standard correlation is expressed in differential form to allow for the nonuniform free-stream flow in the nozzle. Liquid film lengths are well predicted by the model. Downstream of the dry-out point, wall temperatures are well predicted up to the start of convergence. Downstream of the converging turn, a correction term, correlated by a centrifugal parameter, is required to account for increased mixing at the converging turn. Downstream of the throat, wall temperatures decrease very quickly because of acceleration of the boundary- layer gases, an effect not included in the model.

Subject Categories:

  • Thermodynamics
  • Liquid Propellant Rocket Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE