Effect of Simulated Jet Engines on the Flowfield behind a Swept-Back Wing

Abstract

Measurements of the vortex behind a swept-back wing have been made in a low-speed wind tunnel. Results have been taken with a clean wing, with engines mounted in representative positions, and with and without jet exhaust simulation. Only cruising flight conditions are simulated. Loading on the wing has been obtained from pressure distribution measurements. Flowfield properties and the rolling moment on a trailing wing have been measured at 2Vz and 5 wing spans downstream. The concentrated tip vortex structure is essentially unaffected by the engines but the remaining shear layers are considerably distorted by the pylon-nacelles. The maximum induced rolling moment on the trailing wing is only slightly reduced by the present engine installation or the simulated jet exhaust.