Abstract
An isolator is a device that connects the inlet and combustion chambers of RAMJET or SCRAMJET engines. The isolator will slow down the flow and increase static pressure with the help of the shock system formed inside. When the pressure at the combustor end increases, the shock system will move upstream. Eventually, it may become a detached bow shock, reducing the desired mass flow rate and causing the engine to unstart. The flow field inside a 2D Scramjet isolator is studied in this work. The OpenFOAM environment is used for the simulation. The effect of the ramp angle and Mach number on the flow field and unstart velocities have been studied. The maximum pressure ratio was found to be increasing with an increase in ramp angle or with an increase in Mach number. The average normalized propagation velocities calculated using two extreme points show that the normalized unstart velocity increases as the ramp angle increases. At the same time, it is found to be decreasing with increasing Mach number.
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Arjun, P., Nagaraja, S.R. (2023). Unstart Phenomenon in a Scramjet Engine Isolator. In: Revankar, S., Muduli, K., Sahu, D. (eds) Recent Advances in Thermofluids and Manufacturing Engineering. Lecture Notes in Mechanical Engineering. Springer, Singapore. https://doi.org/10.1007/978-981-19-4388-1_18
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DOI: https://doi.org/10.1007/978-981-19-4388-1_18
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