Experimental analysis of the interaction of carbon and silicon ablation products with expanding hypersonic flows
Document Type
Conference Proceeding
Publication Date
9-15-2018
Abstract
Thermal protection is required for vehicles entering planetary atmospheres to protect against the severe heating loads experienced. Characterization of candidate materials is often done utilizing plasma or arc-jet facilities, which provide steady-state testing of the thermal environments experienced during hypersonic flight, but do not correctly simulate hypersonic flowfields. Conversely, impulse facilities can reproduce flight velocities and enthalpies but have extremely short test times, prohibiting testing of thermal response. To better understand how these materials interact with hypersonic flows, experiments were conducted at the X2 expansion tunnel at the University of Queensland. Preheated strips of carbon-carbon and silicon carbide-coated carbon-carbon were mounted in a two-dimensional compression wedge and tested in Earth entry flow, marking the first time silicon carbide has been investigated in this facility. Calibrated spectral measurements were obtained in the near-stagnation and expansion regions for surface temperatures from 1900 K to 2600 K. Cyanogen emissions dominated while atomic silicon and dicarbon were also observed. Emissions for both materials displayed a similar increase near the wall, while emissions for silicon carbide-coated samples displayed a distinct rise downstream of the shock, which suggests a higher concentration of ablative species resulting from a higher ablation rate.
Source Publication
22nd AIAA International Space Planes and Hypersonics Systems and Technologies Conference
Recommended Citation
Donegan, B. E., Greendyke, R. B., Ravichandran, R., Lewis, S. W., Morgan, R. G., McIntyre, T. J., & Apostolov, Z. D. (2018, September). Experimental analysis of the interaction of carbon and silicon ablation products with expanding hypersonic flows. 22nd AIAA International Space Planes and Hypersonics Systems and Technologies Conference. https://doi.org/10.2514/6.2018-5325
Comments
This conference paper is available from the publisher, AIAA, through subscription or purchase using the DOI link below.
Conference Session: Hypersonics Test and Evaluation III
Author note: Brian Donegan was an AFIT PhD candidate at the time of this conference. (AFIT-ENY-DS-18-D-035, December 2018)