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Euler Calculations at Off-Design Conditions for an Inlet of Inward Turning RBCC-SSTO VehicleThe inviscid performance of an inward turning inlet design is calculated computationally for the first time. Hypersonic vehicle designs based on the inward turning inlets have been shown analytically to have increased effective specific impulse and lower heat load than comparably designed vehicles with two-dimensional inlets. The inward turning inlets are designed inversely from inviscid stream surfaces of known flow fields. The computational study is performed on a Mach 12 inlet design to validate the performance predicted by the design code (HAVDAC) and calculate its off-design Mach number performance. The three-dimensional Euler equations are solved for Mach 4, 8, and 12 using a software package called SAM, which consists of an unstructured mesh generator (SAMmesh), a three-dimensional unstructured mesh flow solver (SAMcfd), and a CAD-based software (SAMcad). The computed momentum averaged inlet throat pressure is within 6% of the design inlet throat pressure. The mass-flux at the inlet throat is also within 7 % of the value predicted by the design code thereby validating the accuracy of the design code. The off-design Mach number results show that flow spillage is minimal, and the variation in the mass capture ratio with Mach number is comparable to an ideal 2-D inlet. The results from the inviscid flow calculations of a Mach 12 inward turning inlet indicate that the inlet design has very good on and off-design performance which makes it a promising design candidate for future air-breathing hypersonic vehicles.
Document ID
19990079881
Document Type
Conference Paper
Authors
Takashima, N. (Astrox Corp. Hampton, VA United States)
Kothari, A. P. (Astrox Corp. Rockville, MD United States)
Date Acquired
August 19, 2013
Publication Date
July 1, 1998
Publication Information
Publication: 1998 JANNAF Propulsion Meeting
Volume: 1
Subject Category
Aircraft Design, Testing and Performance
Funding Number(s)
CONTRACT_GRANT: NAS8-97254
CONTRACT_GRANT: NAS1-20060
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle19990079846Analytic Primary1998 JANNAF Propulsion Meeting