【6A文】航空飞机液压理论英文培训课件.ppt

《【6A文】航空飞机液压理论英文培训课件.ppt》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、HydraulicsAirlineTransitionCourseLessonObjectivesDevelopabasicunderstandingofhydraulictheoryandthephysicsrelatedtohydraulicsFluidPowerLawofConservationofEnergyPascal’sLawHydrostaticParadoxMechanicaladvantageBernoulli’sprincipleTypesofFluidHydraulicSystemCom

2、ponentsFluidPowerTHEORYHydraulicsystemsoperateaccordingtoPascalslaw.ThelawofBlaisePascalsays:'Thepressure,inastatichydraulicfluidinaclosedsystemiseverywherethesame'.However,whenthevelocityoftheflowisconstantonemayapplyPascalsLawaswell.Animation:Whenthemanj

3、umpsonthesmallpiston,heinducesapressureinthesystem.Thispressurealsoworksonthelargepiston:becauseofthelargeareaofthispiston,theforceinducedbythepressureiscapabletoliftthecar.Thepressurecanbecalculatedwiththeformula:where:p=pressure(psi)F=force(pound)A=area(s

4、quareinch)FluidPowerForce=energyexerted(F=MA)Pressure=aforcethatisappliedoveragivenarea(usuallyinpsi)Pressure=Force/AreaWork=anytimeaforcecausesanobjecttomoveWork=ForcexDistancePower=theamountofpowerrequiredtoaccomplishagiveamountofworkinacertainperiodoftim

5、ePower=(ForcexDistance)/TimeLawofConservationofEnergyWeareabletotakeenergyandchangeit’sform,conserveitforlater,andreleaseitatwill.Wegetthesameamountofenergyoutasweputin.Unfortunatelysomeenergyistransformedandlostintoanunusableform.Ex:Rubbingyouhandstogether

6、,takesyourbodiesenergyandreleasesitasthermalenergy.(UnlessyourinNorthDakotainJan.doingthisisusuallyprettyuseless)ThislossofenergyisusuallyreferredtoasinefficiencyTwoFormsofEnergyPotential:ExistsinanobjectbecauseofitspositionEx:ArubberbandstretchedoutKinetic

7、:ExistsinanobjectduetoitsmotionEx:ArubberbandafterIhaveletgoofit,asitfliestowardsyourfaceHydrostaticParadoxParadox:Atruestatementthatdoesnotreadilyappeartobetrue.HydrostaticParadox:Thepressureofafluidatthebottomofthecontainerwillbeeffectedbytheheightofthatc

8、ontainerbutnotitsshapeortheamountoffluid.Pascal’sLaw“Pressureinanenclosedcontaineristransmittedequallyandundiminishedtoallpartsofthecontainerandactsatrightanglestotheenclosingwalls.Pascal’sLawPressuree