Purdue University - School of Aeronautics and Astronautics

AAE 520 Experimental Aerodynamics

V=0 to 100 voltsI = 0 to .5 amp

Electrode (somewhere in flow tank)

Bubble Wire (~.001” dia.) Platinum – expensive &weak Tungsten – high strength Steel – stainless does not corrode Aluminum - weak

Frame

Electrolysis of WaterForms Hydrogen Bubbleson Small Diameter Wire

Water must be conductiveHard water (Lafayette) is conductive but calcium deposits on wireCan add Sodium Sulfate to adjust the conductivity

Lighting is Critical – Forward Scatter when possible

Hydrogen Bubble WireAAE 33l Fluid Mechanics Laboratory

Purdue University - School of Aeronautics and Astronautics

AAE 520 Experimental Aerodynamics

eHgOOH

OHgHOHe

gOgHOHOHHgOgHOH

24)(2 Electrode) (Positive Anode

2)(22 Electrode) (Negative Cathode

)()(2244)()(26

Waterof isElectrolys

22

22

222

222

Can form either Hydrogen or Oxygen BubblesHydrogen Bubbles – smaller less buoyant harder to seeOxygen Bubbles – larger more buoyant easier to see

Hydrogen Bubble MethodAAE 33l Fluid Mechanics Laboratory

Purdue University - School of Aeronautics and Astronautics

AAE 520 Experimental Aerodynamics

Pulse Wire – Measure Velocity

AAE 33l Fluid Mechanics Laboratory