Numerical Investigation of the Applicability of a Single Ramp Supersonic Inlet for Ramjet Propulsion
Franciszek Dominik TOMCZAK
Abstract. In this work, we investigate the applicability and performance limitations of a single-ramp, external-compression inlet for ramjet propulsion over a range of supersonic Mach numbers. The current work examines the use of strong oblique shocks instead of terminal normal shocks to enhance inlet performance and reduce the total pressure losses in simplified geometries. A combined analytical and numerical approach is used. Oblique shock theory and the Oswatitsch criterion for optimal multi-shock compression are employed to estimate the performance limitations of the multi-ramp configuration. The analytical predictions are then validated using high-fidelity CFD simulations performed with ANSYS Fluent. The results show that the single-ramp inlets are efficient at lower supersonic speeds (up to approximately Mach 2) due to the use of a strong oblique terminal shock. However, their efficiency deteriorates rapidly at higher Mach numbers, significantly increasing the total pressure losses. Analytical models slightly overpredict pressure recovery by 1.5–2% compared to numerical results. The current work aims to provide insight into the performance envelope of simplified inlet geometries for high-speed air-breathing propulsion systems. The research demonstrates the benefits and trade-offs of various ramp designs and highlights the necessity of more complex geometries, such as multi-ramp designs, for efficient operation at Mach numbers exceeding 2. These findings can support the optimization of a ramjet inlet design and provide guidelines for the development of future propulsion systems.
Keywords
Supersonic Inlet, External Compression Inlet, Strong Oblique Shock Wave, Total Pressure Recovery, Ramjet Propulsion, Numerical Simulation (CFD)
Published online 7/20/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Franciszek Dominik TOMCZAK, Numerical Investigation of the Applicability of a Single Ramp Supersonic Inlet for Ramjet Propulsion, Materials Research Proceedings, Vol. 69, pp 626-631, 2026
DOI: https://doi.org/10.21741/9781644904251-111
The article was published as article 111 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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