AerE L AerEL Lecture Notes Lecture # 5: Airfoil Wake Measureets ad Calibratio of a Hotwire Aeoeter r. Hui H Hu eartet of Aerosace Egieerig Iowa State iversit Aes, Iowa 5,.S.A Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved!
Objectives of AerELL Objectives of the aerodaic lab courses:. To hel studets to gras cocets ad fudaetal riciles taught i aerodaics courses.. To rovide studets ore chaces to get hads-o lab exerieces.. To teach studets basic kowledge related to exerietal aerodaics ad easureets techiques.. To irove studets caabilities i egieerig writig b writig lab reorts. 5. To roote the sirit of tea-work aog the egieerig studets. Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved!
AerELAerEL Gro ivisio Over 9 studets divided ito 6 lab sectios gros er sectio ~5 studets er gro Lab liitatios: ol oe set of exerietal facilit oe wid tuel oe test odel Studets colais ad cocers: TAs re-lab lecture is too log TAs will tr to fiish the exlaatio withi iutes Waitig tie is too log, ca we have gros/sectio ~8 studets er gro istead of gros/sectios ~5 studets er gro? eeds o the oiios of ajorit of the studets Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved!
Lab : Airfoil Wake Measureets ad Hotwire Aeoeter Calibratio io Estiatios of the lift ad drag coefficiets of a airfoil Method : airfoil surface ressure easureets: Y iches..5..5..5 -.5 -. -.5 -. -.5 5 5 -. 5 6 7 8 9 -. X iches NACA airfoil 5 7 -.5 -. er surface lower surface -.5 C -. -.5.5..5.....5.6.7.8.9. x / c Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved!
Lab : Airfoil Wake Measureets ad Hotwire Aeoeter Calibratio io Method : airfoil wake easureets: t C d ˆ CS F x For stead flow: d t C CS ˆ ˆ ˆ Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved!
Coright Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved! b r. Hui Hu @ Iowa State iversit. All Rights Reserved! x Sice boudar ad is far awa fro the airfoil: Sice boudar ad is far awa fro the airfoil: ] ] ] ] ] ˆ ˆ ˆ ˆ ˆ CS Lab : Airfoil Wake Measureets ad Hotwire Aeoeter Calibrat Lab : Airfoil Wake Measureets ad Hotwire Aeoeter Calibratio io ˆ ; ˆ ˆ ˆ Coservatio of ass: Coservatio of ass: ] ˆ d t CS C r
Coright Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved! b r. Hui Hu @ Iowa State iversit. All Rights Reserved! x Lab : Airfoil Wake Measureets ad Hotwire Aeoeter Calibrat Lab : Airfoil Wake Measureets ad Hotwire Aeoeter Calibratio io ; ] ] Sice ˆ F F F X X CS X X ] ] d C C C C C Coared with the drag coefficiets obtaied based o airfoil s Coared with the drag coefficiets obtaied based o airfoil surface urface ressure easureets lab# at the sae agles of attack! ressure easureets lab# at the sae agles of attack!
Lab : Airfoil Wake Measureets ad Hotwire Aeoeter Calibratio io Pressure rake with total ressure robes the distace betwee the robes d x 8 Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved!
Lab : Airfoil Wake Measureets ad Hotwire Aeoeter Calibratio io Flow Field Curret flow through wire c dt dt w i R w q Costat-teerature teerature aeoetr, T w CTA hotwire robe Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved!
Hotwire Aeoeter Calibratio To quatif the relatioshi betwee the flow velocit ad voltage outut fro the CTA robe Flow velocit /s 8 6 8 6 abxcx d*x e*x ax dev:.66, r. a.8, b.77, c-6.6, d. Curve fittig Exerietal data......5.6.7.8.9... voltage Coright b r. Hui Hu @ Iowa State iversit. All Rights Reserved!