Numerical investigation of inlet distortion in a jet engine coupled with Ski-jump of carrier-based aircraft

Abstract

Contract with land-based aviation, the ski-jump of carrier-based aircraft is confronted with complicated aerodynamic circumstances. More especially, the occurrence of inlet distortion in the aero-engine would endanger its flight safety. This study conducted the inlet distortion of the aero-engine coupled with the ski-jump of carrier-based aircraft by means of numerical simulation. The movement of the aircraft has been characterized by the nested dynamic grid and user-defined function (UDF). The results show that the inlet distortion of the aero-engine has resulted from the suction of high-temperature exhaust gas from the auxiliary intake grille primarily and the aero-engine inlet subsequently. the presence of an intersection angle between the aircraft axis and carrier axis has brought the accumulation of the high-temperature exhaust gas near the left engine while the sucking of flow into the right engine is ‘fresh air’ in the ambiance. Correspondingly, the inlet distortion of the left engine is larger than that of the right engine. For the braking state, the region-averaged relative temperature rises at the AIP section increased by 27.46% compared with the land case. For the slip-jump, the temperature and pressure distortion at the AIP section decreases rapidly with the increase of the slip-jump distance. After the slip-jump distance is greater than 6m, the total temperature and total pressure distortion almost disappeared. The increase in aircraft height, the velocity magnitude of relative wind velocity, and the distance from the take-off point to the Jet Blast Deflector decreased the inlet distortion of the aero-engine. The relative wind from the left wing (α<0°) brought more inlet distortion to the right engine while the relative wind from the right wing (α>0°) brought more inlet distortion to the left engine. The results obtained in this study are significant because they provide the physical mechanism of inlet distortion of aero-engine and can be used for the guidance of the operational safety of carrier-based aircraft.