Computational Investigation of Flow Through a Louvered Inlet Configuration

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2002-9

Author

Tuncer, İsmail Hakkı

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The aerodynamic analysis of subsonic lifting body concepts for future unmanned air vehicles and missiles has been an active research held in recent years. A lifting body combines three emerging technologies, namely, lifting body, thrust vector control,and flush louvered inlet. The flush louvered inlet configuration requires the flow to turn 360 deg in the plenum chamber before entering the engine. The pressure losses and flow distortions experienced in the plenum chamber are serious concerns. In the analysis of the flow, the boundary-layer buildup on the underside of the missile body before reaching the louvered inlet and the three dimensional flow in the plenum chamber are to be accounted for. Engine tests simulating flows through such an inlet configuration are currently not possible. It is, therefore, highly desirable to compute viscous, compressible flows through a typical flush louvered inlet configuration. In this work, a numerical study of viscous, subsonic flow through a louvered inlet configuration is performed. In the design of louvered inlets, inlet vanes are required to achieve good total pressure recovery. However, in this analysis, the inlet vanes are not modeled to simplify the computational domain. Preliminary flow solutions of this highly complex flow field are first obtained, and the variation of the mass flow rate and the total pressure recovery at the engine intake is evaluated as a function of the imposed intake pressure. The Navier–Stokes solver, OVERFLOW (ver. 1.7v), is used to compute the flow through the louvered inlet configuration.OVERFLOW, which was developed at NASA Ames Research Center, is a compressible,thin-layer,Reynolds averaged Navier–Stokes solver.1 It accommodates computational domains discretized with overset subgrids.Overset subgrids are preprocessed with the PEGSUS code, which determines the intergrid boundaries created by the overset subgrids.At the intergrid boundaries,OVERFLOW interpolates the flow variables from the neighboring donor subgrids. PEGSUS provides the intergrid interpolation stencils and the corresponding interpolation weights to OVERFLOW. In the past, we have successfully computed viscous flow fields over missile configurations using OVERFLOW.

URI

https://hdl.handle.net/11511/28175

Journal

Journal of Aircraft

DOI

https://doi.org/10.2514/2.3016

Collections

Department of Aerospace Engineering, Article

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Citation Formats

İ. H. Tuncer, “Computational Investigation of Flow Through a Louvered Inlet Configuration,” Journal of Aircraft, pp. 903–906, 2002, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/28175.