Pylon Modification Study for Optimizing the Wing-Engine Integration of the Fairchild/Dornier 728 Jet Aircraft

Kurzfassung

A numerical investigation is carried out to optimize the engine/airframe integration of closely coupled engines on a twin-jet regional transport aircraft in cruise flight condition. Since the engine position variation cannot be efficiently applied for such closely coupled engines, the optimization of the engine integration is performed by modifying the pylon, wing and engine. This investigation shows that pylon contour modifications enable an optimization of the engine integration. The modification of the pylon geometry within the jet stream dominates the engine interference on the wing since it changes the characteristics of the jet stream so that the tunnel effects are reduced significantly. The modification of the pylon geometry outside of the jet stream leads only to an insignificant change of the engine interference on the wing. Therefore the wing modification does not hold promise for a superior optimization of the engine integration. Furthermore, the jet stream can be also influenced by modifying the engine core cowl. The investigation shows that a small change on the core cowl contour reduces the engine interference on the wing considerably.