Accession Number:

ADA445014

Title:

Experimental and Numerical Analysis of Transpiration Cooling of a Rocket Engine Using Lamilloy (Trademark) Plates (POSTPRINT)

Descriptive Note:

Technical paper

Corporate Author:

NORTHROP GRUMMAN SPACE AND MISSILE SYSTEMS CORP REDONDO BEACH CA SPACE TECHNOLOGY

Report Date:

2005-12-01

Pagination or Media Count:

13.0

Abstract:

Transpiration cooling of rocket engine thrust chamber walls has the potential for improving the performance of liquid rocket engines by reducing the required cooling flow. For the TR107 hydrocarbon booster engine, it is estimated that replacing the proposed chamber wall film cooling with transpiration cooling could result in an engine Isp increase of 2 to 3, which provides the potential to increase the maximum booster delivery capability by 4000-5000 lbm. In the past, various transpiration cooling wall materials have been investigated with varying degrees of success. In this investigation we examined the use of Lamilloy as the transpirant wall. Lamilloy is a cooling system with a 30 year history in jet engine applications developed by Rolls-Royce LibertyWorks. This work represents the first evaluation of this technology for rocket engine applications in a representative hot-fire environment. Tests were performed in a sub-scale hot-fire chamber that produced heat fluxes of 4-15 Btuin.2s at chamber pressures of 370-670 psi. Gaseous oxygenRP-1 propellants were fired at mixture ratios ranging from 1.2 to 1.8. Three off-the-shelf Lamilloy designs were tested with three different transpirants gaseous nitrogen, water, and RP-1. Testing demonstrated that the hot-gas wall temperature decreased rapidly in the downstream direction due to the cumulative effect of the injected coolant. The tested Lamilloy specimens demonstrated the potential to be an effective material for use as a transpiration cooled wall. However, the specimens tested were designed for low pressure drop in gas turbine combustor applications thus did not provide the high pressure drop needed for rocket propulsion applications. The extensive database generated during this testing can be used to guide future Lamilloy transpiration cooling designs for specific rocket thrust chamber applicat

Subject Categories:

  • Liquid Propellant Rocket Engines
  • Properties of Metals and Alloys
  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE