Methodology for full-body TPS sizing of Access-to-Space vehicles

Abstract

AIAA 34th Aerospace Sciences Meeting and Exhibit, Reno, NV Jan 15-18, 1996Methodology and numerical procedures developed at NASA Ames for full-body thermal protection system sizing are documented. The core procedure is a robust implicit solver for one dimensional transient heat conduction in multilayer stacks of reusable thermal protection and structural materials. The solver includes an arbitrary number of material layers, contact resistances between materials, temperature and pressure dependent material properties, general boundary-condition options, and self-adaptive time stepping. A menu driven Graphical User Interface is used to couple the solver with an Access-to-Space material database of candidate thermal protection and structural materials and with a thermal-environment database obtained from trajectory-based full-body Navier-Stokes computations of the external flowfield, to analyze and visualize the time-dependent thermal response of the thermal protection system, and to create and modify material mapping data files. Examples of thermal protection system sizing are presented, including results for a single-stage-to-orbit rocket vehicle concept. (Author) AbstractMethodology and numerical procedures developed at NASA Ames for full-body thermal protection system sizing are documented. The core procedure is a robust implicit solver for one dimensional transient heat conduction in multilayer stacks of reusable thermal protection and structural materials. The solver includes an arbitrary number of material layers, contact resistances between materials, temperature and pressure dependent material properties, general boundary-condition options, and selfadaptive time stepping. A menu driven Graphical User Interface is used to couple the solver with an Access-toSpace material database of candidate thermal protection and structural materials and with a thermal-environment database obtained from trajectory-based full-body Navier-

Ablation and thermal response program for spacecraft heatshield analysis

“…The block matrix solver in the FIAT code is the same as that used in the One-dimensional Multi-Layer Implicit Thermal Solver (OMLITS). 16 Details of this matrix solver are provided in Ref. 16 and are not discussed in this paper.…”

Integrated design system for dynamic thermal protection system sizing

“…Re tri = (Re θ ) tri ; Ma etri is the Mach number at the beginning of transition region; S is the distance along the inviscid surface streamline; S tri is the distance along the streamline where the transition begins, and S tre is the distance along the streamline where the transition ends. The end of transition region can be obtained from equation (1). Third, several selected transition correlations are inserted into the method developed by DeJarnette [5] to predict the beginning of the transition region, such as the geometric location correlation [5], the Timmer/Baker transition correlation, the Passive Nose-Tip Technology program (PANT) transition correlation, and (Re θ /Ma e ) tri = C. Ma θ is the Mach number at the edge of boundary layer.…”

“…The methodologies for TPS sizing were developed by Milos et al [1] and Olynick [2], and belong to static TPS sizing according to the differences between 'static' provides an optimization of the minimum thickness of the TPS materials required to prevent the vehicle structure from exceeding its operating temperature limit, and to obtain a lower total TPS weight. The GUI provides a three-dimensional data visualization and animation capability of the transient temperature contours over the surface of vehicle, which can be modified interactively.…”

“…The methodologies for TPS sizing were developed by Milos et al [1] and Olynick [2], and belong to static TPS sizing according to the differences between 'static' and 'dynamic' TPS sizing [3,4]. Based on the concept of dynamic TPS sizing, Cowart and Olds [4] developed a tool for automated TPS design, in which the aeroheating was predicted by the fast engineering code MINIVER (MINIature VERsion aero-thermal analysis program) because dynamic TPS sizing calls for continuous updating of TPS parameters as the design process proceeds.…”