Structural Index Parameter for Capturing Structural & Aerothermal Effects in Conceptual Level Vehicle Design

Abstract

The three phases of vehicle conceptual design include parametric sizing, configuration layout, and configuration evaluation. During the parametric sizing phase, the ability to define and quantify the technology level of an aerospace system allows the assessment of candidate designs based on feasibility given current technology or indicates if one must advance a particular technology. To meet this need, the structural Index (Istr) parameter merits exploration to consider structural and aerothermal effects during the parametric sizing phase of conceptual design given materials, structural concepts, and manufacturing capability. This study showcases the utility of this structural/materials technology parameter for high-speed vehicles by modernizing and expanding upon Paul Czysz\u27s original structural index (Istr) versus the surface temperature map. The modernized and expanded structural index (Istr) map is constructed by selecting a temperature-through-thickness method for a given thermal protection system (TPS) that simplifies a given surface temperature and atmospheric pressure profile into a constant heat pulse. One can then size the TPS to keep the structural temperature within material limits. The newly generated structural index (Istr) maps allow one to observe trends with variations in surface temperature, cruise time, average atmospheric pressure (Pavg), and TPS materials