Performance and Flow Characteristics of Double-Offset Y-Shaped Aircraft Intake Ducts

Abstract

A Y-shaped intake duct is a critical component of a single-engine modern combat aircraft. The present study is an attempt to establish the flow behavior of a double-offset Y duct with uniform wall roughness with a semi-elliptical ' inlet and a circular exit. These studies are carried out using the commercial computational fluid dynamics code FLUENT with a renormalized-group k-e turbulence model. An attempt was made to establish the effect of Reynolds number and vertical offset on the flow characteristics of a double-offset Y duct for a fixed horizontal offset. It is seen that performance and flow characteristics of the duct are independent of Reynolds number for Re > 105. In the presence of a vertical offset, the core of the flow moves along the diagonal plane, which is inclined to the vertical axis at an angle determined by the magnitude of the vertical offset (a 15/15-deg offset gives an angle of 30 deg).