Evaluation of Aerothermochemistry Models Through Sensitivity Analysis and Low-Uncertainty Experiments
Abstract
A critical phenomenon in the design of hypersonic vehicles is thermochemistry in the air flowing around the vehicle. Chemical reactions affect the thermodynamic state of the air and can increase heat transfer and cause ablation. Recently, there has been significant progress in the U.S. academic community to advance our understanding of air chemistry. A database of the most important air chemistry mechanisms is nearing completion, but there is a major gap limiting the adoption of the new rate information. Specifically, published experimental data sets have insufficient fidelity to allow determination of potential improvements of the new models. We propose to address this gap through research involving close coupling between modeling and experiment. The modeling at Colorado will use flow codes for analysis of shock tubes and multi-dimensional hypersonic flows. The experiments will be conducted at Stanford in a shock tube facility using laser diagnostics. The project has several closely coordinated elements- - Sensitivity analyses of hypersonic flow conditions to determine the key aerothermochemistry mechanisms and associated temperature regimes that most affect the quantities of interest. These analyses will also assess the level of uncertainty in measurements that is required to discriminate between the new and old aerothermochemistry models. - The results of the sensitivity analyses will also inform the design and execution of detailed shock tube experiments at Stanford in terms of species interactions in air, flow conditions, diagnostics, and required levels of measurement uncertainty. - The Stanford shock tube experiments will be modeled and used to evaluate the existing state-resolved aerothermochemistry models for both internal energy activation and chemistry. - The models validated using the low-uncertainty shock tube data will be applied to new shock tunnel experiments for which flow field and surface data are available.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 07, 2023
- Source ID
- FA95502110075
Entities
People
- Iain D. Boyd
Organizations
- Air Force Office of Scientific Research
- Regents of the University of Colorado
- United States Air Force