particle image velocimetry of a hypoxia chamber

Adaptation of the PIV System to the Analysis of Flow Fields in a Hypoxia

Chamber

Alvin ZhangMichael SanfeliceYevgeniy Yesilevskiy

ME160 Engineering Experimentation: Section A Group 2

Background

Taken from LaVision

Application to Wind Tunnel

Laser

Laser Sheet

Air Flow

Seed Particles

Camera

From Diouf, Penn State University

Two separate images

User-defined grid is placed

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Images are overlaid

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Vector field is calculated

Adapting the Hypoxia Chamber for PIV

Slanted Sides

Improve Clarity

Introduce Seed Particles

From Caubel , Foley, Todorov: Optimization of a Laboratory Animal Enclosure for the Study of

Sleep Apnea

Cage Redesign

Seeding the Cage

Compressed Air Inlet

Oil Container

Adjustment Knob

Seed Outlet

Laser Absorber

Seed Exit

Chimney

Side Facing Camera

Side Facing Laser

Seed Particle

Inlet

Image Taking Setup

Power Supply Inputs and

Cooling Input

Mirror

Beam Spreader

Output to Computer

Tripod

Camera Focus

Considerations

•Cross Flow▫Causes inaccurate vector field.

•The seed particles have many different velocities▫The vector field is very sensitive to the dt

choice

Seed particles

Time Step too Long

Actual Motion

Perceived Motion

Good Time Step Selection

Choosing Correct Time Step

JUM February 1, 2011 vol. 30 no. 2

187-195

Choosing Correct Time Step

Without Diffuser

Position [mm]

Posi

tion

[m

m]

Without Diffuser

Without Diffuser

Without Diffuser

Without Diffuser

Without Diffuser

Without Diffuser

With Diffuser

With Diffuser

With Diffuser

With Diffuser

With Diffuser

With Diffuser

With Diffuser

With Diffuser

With Diffuser

With Diffuser

Conclusions and Recommendations

•Characterize random uncertainty•Calibrate measurement axes.•Improve procedure for choosing dt•Measure steady state velocities•Multiple chimneys•Fans

Acknowledgements

•Thank you to Professors Delagrammatikas, Sidebotham, and Consiglio for help in compiling this study.

•Thank you also to LaVision representative Steve Anderson

Powerpoint outline• General PIV background (i.e. for wind tunnel)• Flow: Very well suited for wind tunnel, this is how it applies to

hypoxia• Specific Application to Hypoxia project (Box Design and the

video you made)• Flow: How was that put into practice?• Schematic of set up downstairs (Autocad or actual pictures)• Flow: Now that system is made, how to get results?• Process to take measurements (screen shots)• Flow: Analyze those measurements• Results• Flow: How meaningful are they? • Error• Conclusion and Recommendations