Volume 3, Issue 5 (September 1975)
Contamination Damage Avoidance Concepts for Propulsion Feed System Components
The gain in component reliability for long-term, reusable space vehicles was investigated in a two-part program. Mechanical redesign methods were used to minimize contamination damage of conventional components and a unique type of contamination separator device was developed. The redesign techniques were incorporated into an existing 2-in. (50.8-mn) poppet value and tested for damage tolerance in a full-size open-loop system with gaseous and liquid nitrogen. Cyclic and steady flow conditions were tested with particles of 75 to 200-µm aluminum oxide dispersed in the test fluids. Nonflow cycle life tests (100,000 cycles) were made with three valve configurations in gaseous hydrogen. The redesign valve had an acceptable cycle life and improved tolerance to contamination damage.
Analytical studies were completed on various types of dynamic separator. A venturi type of particulate separator was fabricated and preliminary testing completed in the gaseous nitrogen test system at 200-ft/s (61-m/s) velocity.