Authors : Ahyaan Bondre

Volume/Issue : Volume 11 - 2026, Issue 1 - January

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Google Scholar : https://tinyurl.com/6a7nrrc3

Scribd : https://tinyurl.com/33dm3dfx

DOI : https://doi.org/10.38124/ijisrt/26jan1332

Note : A published paper may take 4-5 working days from the publication date to appear in PlumX Metrics, Semantic Scholar, and ResearchGate.

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Abstract : This paper investigates the theoretical performance of a combined-cycle propulsion system integrating turbojet and ramjet engines. Turbojets operate effectively in subsonic and transonic regimes, while ramjets excel in supersonic conditions but require high inlet speeds to function. A hybrid engine allows a supersonic vehice to operate efficiently across a wide Mach range. Using thrust equations, Brayton cycle efficiency, and Rayleigh flow theory, this paper models the performance of both engine types and identifies transition conditions for optimal operation.

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