Optimization of S-Shaped Inlet Diffuser for Improvement of Total Pressure Loss and Flow Uniformity

Document Type : Research Article

Authors

Aerospace Engineering Department, Amirkabir University of Technology, Tehran, Iran

Abstract

The intake is a part of the aero engine, which provides air to the compressor uniformly and with a minimum total pressure loss. Today, due to the abundant application of S-shaped inlets, optimization of these diffusers has been considered by many researchers. The uniform distribution of the flow at the inlet of the compressor has a direct effect on engine performance. On the other hand, the flow separation through the duct reduces the pressure recovery and the engine thrust. In this article, an S-duct intake has been optimized to reduce the total pressure loss and flow distortion. The neural network, coupled with the genetic algorithm, is used to optimize the objective functions in the shortest possible time. Two optimization cases have been done. In the first case, new geometries have been generated by changing the centerline coordinate and the cross-sectional area ratios. The first optimization results in an enhancement of 32.5% for the pressure recovery coefficient and a reduction of 35.8% for flow distortion. In the second optimization, the length of the duct has also been decreased. By decreasing the length of the duct, the weight of the aerial vehicle is reduced, and on the other hand, the useful space inside the body is increased. This optimization gave an enhancement of 35.96% for pressure recovery coefficient and a reduction of 39.4% for flow distortion and a 25% reduction in the duct length.

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References

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Amirkabir Journal of Mechanical Engineering
Volume 52, Issue 11
February 2021
Pages 3171-3186

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