Time-Varying Entry Heating Profile Replication with a Rotating Arc Jet Test Article

Grinstead, Jay H.; Venkatapathy, Ethiraj; Noyes, Eric A.; Mach, Jeffrey J.; Empey, Daniel Martin; Prabhu, Dinesh K.; White, Todd Richard

NASA NTRS · 20190001656

Time-Varying Entry Heating Profile Replication with a Rotating Arc Jet Test Article

Grinstead, Jay H.·Venkatapathy, Ethiraj·Noyes, Eric A.·Mach, Jeffrey J.·Empey, Daniel Martin·Prabhu, Dinesh K.·White, Todd Richard

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Abstract

A new approach to arc jet testing that replicates the time-varying conditions of atmospheric entry heating was demonstrated. The concept relies on the spatial variation of heat flux and pressure around a cylindrical test article. The spatial variation is transformed to a temporal variation at one location by rotating the test article during exposure to the arc jet stream. The test article rotation mechanism is based on a programmable stepper motor. An entry heat flux profile was mapped to the cylinders heat flux distribution to determine the rotation angle vs. time executed by the mechanism. A series of arc jet tests with instrumented cylindrical TPS test articles was conducted to prove the concept.

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BibTeX RIS

Grinstead, Jay H., Venkatapathy, Ethiraj, Noyes, Eric A., Mach, Jeffrey J., Empey, Daniel Martin, Prabhu, Dinesh K., White, Todd Richard. 2018-06-16. Time-Varying Entry Heating Profile Replication with a Rotating Arc Jet Test Article. https://ntrs.nasa.gov/citations/20190001656

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