Multiwall TPS-An Emerging Concept

This paper reviews some of the effort required to transform one thermal protection system concept, titanium multiwall, from a conceptual design to a practical working reality. Gradually, from continuing analytical and experimental studies, a fundamental understanding of the thermal and structural performance of the basic multiwall concept is evolving. In addition, radiant heat, wind-tunnel, vibration, acoustic, and lightning strike tests are being used to verify the performance of multiwall tiles under representative operating conditions, and flight tests of a large array of tiles are planned as part of an Orbiter experiments program. Results of the tests are being used to improve the design, and a mature technology is emerging. To date, research has focused on flat all-titanium multiwall configurations, which are limited to temperatures below 810 K (1000 degree F); however, the effort is being extended to include curved surfaces and higher temperature versions of the multiwall concept.