模型蜻蜓翼動態(tài)柔性變形下氣動效應(yīng)的理論?；芯?pdf

1、中國科學(xué)技術(shù)大學(xué)碩士學(xué)位論文模型蜻蜓翼動態(tài)柔性變形下氣動效應(yīng)的理論?；芯啃彰盒烀魃暾垖W(xué)位級別：碩士專業(yè)：流體力學(xué)指導(dǎo)教師：童秉綱余永亮20060501r卜國利學(xué)技術(shù)大學(xué)碩士學(xué)位論文模犁蠟蜒翼動態(tài)萊性變形下氣動效應(yīng)的理論?；芯緼bstractTheaerodynamicresponsetothetime—changingflexibledragonflymodelwing’SdeformationiSinvestigatedinth

2、isthesis，basedontheexperimentaldataFirstly，theflowexitedbydragonflywingsischaracterizedasbeingunsteadyandlOWViSCOHSthatiSStl／ReSOitcanbemodeledtheoretically1nthiSway，theflowissimplifiedtobepotentialApanelmethodisimproved

3、andappliedtothestudyofaflexibledragonflymodelwing，ie，a2dimensionaldeformableplatewithbothsheddingvorticesfromtheleadingandtrailing—edgesItisverifiedthatthisapproachishighlyeffectiveSecondly，theelementarymotions，ie，theacc

4、eleratedtranslationandtherotationunderconstantincomingflow，areinvestigatedTheaddedmasseffectdominatestheincrementofaerodynamicforcesgeneratedbyflexiblewingduringacceleratedtranslationandsupination，andthevortexinducederie

5、ctdoesonlyReartheendofpronationbecausethevorticityflowischangedbytimechangeflexibledeformationFinally，basedOiltheexperimenttheaerodynamicresponsestothetimechangingflexiblewingdeformationduringwingbeatcycleinthedragonflyf

6、orwardflightisinvestigatedTheresultsshowthat：(1)theactualdragonflywingdeformationcanenhancetheliftandthrustgreatlyduringdownstroke，butthelowthrustduringupstroke；thetime—averagedliftandthrustareincreasedby200％and405％respe

7、ctivelyandtheaerodynamicpowerrequirementdeducedby68％inacycle(2)thevortexinducedeffectdominatestheaerodynamiCdifferencesbetweentheflexibleandrigidwingsforalmostallofthecycle(3)theactualamplitudeofthewingdeformationisprope