Aerodynamic Analysis of a Submerged Inlet, Using Numerical Simulation

Document Type : Original Article

Authors

1 Department of Mechanical Eng. Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran

2 School of Mechanical Eng. Sharif University of Technology

3 Mechanical Eng. Group Babol University of Technology

Abstract

In the present study, turbulent flow in submerged inlets was studied, using numerical simulation. In the calculations, three different geometries, namely NACA standard inlet and two geometries with proposed structures were studied and the effects of boundary layer thickness (0.31, 0.8 and 0.56) and 0.2< dimensionless velocity < 1.6 on their performance were investigated.  model was applied to simulate three-dimensional, incompressible, and turbulent flow. At first, NACA standard inlet was validated, using reliable experimental data. Results show that increasing boundary layer thickness has a negative effect on RAM pressure efficiency in all geometries, while velocity increase initially increases the efficiency and then decreases it. In addition, the efficiency of new geometries is close to one for NACA standard inlet. Moreover, the novel geometries are of lower drag force in high velocity ratios and are better NACA standard case.

Keywords


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