Research On Underwing Nacelle Structure Flow Interference And Aerodynamic Optimization

There are mutual interference problems for wing-body-nacelle-pylon configuration, they areenhanced under engine powerd condition.For more information on the configuration and nacellepower condition influence,this research used CFD method,based on DLR-F6model and its changedmodals, calculated the configuration dynamic characters under through flow condition and powercondition separately of some fly status.First,this research compared the calculated results with the experiment results for a rightcalculated method for the next step. Based on the method,simply analysed the interference problem ofthe F6modal. Then calculated the cruise power condition and cruise throughflow condition withDLR-F6modal under different attack angle.The results show nacelle inlet and outlet flow characterschange little with attack angle changes,the trend of the nacelle drag coefficient and the wing lift/dragcharacters change fllow the attack angle`s.Consider the through flow condition,all the configurationcharacters go better under power conditionSecond, this research analyzes the nacelle positions modified models under the wing alongspanwise direction,chordwise direction and vertical direction. The F6modified models under cruisethroughflow and power conditions. The results show that one, the nacelle inlet and outlet flowcharacteristics change little along with the different direction model changing; Two, the dynamiccharacteristics of the components in W-N-P structure nonmonotonously change with the spanwisedirection position changing; Third, as nacelle chordwise direction position was changing,nacelle dragincreased monotonously but wing lift/drag characters changing nonmonotonously; Four, as the heightof the nacelle position was changing, nacelle drag decreased monotonously and the wing lift/dragcharacter changing nonmonotonously.Third,calculated the cruise throughflow condition and cruise power codition base on DLR-F6modal with nacelle vortex generator.The results show that the nacelle vortex generator changesnacelle inlet and outlet characters little under cruise condition.When we fix up the vortex generatormuch more near the nozzle,the nacelle drag coefficient goes bigger,the wing drag coefficint changeslittle and the wing lift coefficient changes by a conic curve.When we changed the vortex generatorsize,the nacelle drag cofficient and the wing lift coefficient change little,the wing drag coefficient isbigger with small size vortex generator. All the configuration characters go better under powercondition Last,calculated the DLR-F6modal under take-off condition and cruise wing dynamic responsecondition,discussed that if the mothed used in steady state was useable under transient condition andanalysed the characters simplely are the objects of the section.The results show the nacelle inlet totalpressure recovery descended obviously because of the ground influence.Under the course of the planenose rising and plane climbing,nacelle power condition fluencies heavily.Wing dynamic responsecondition calculating shows that steady calculate method is useful for some configuration charactersunder transient condition,it can be used in the next step of the problem discussion.