flow : 2D Turbulent Flow Visualization
MEAM302 Optional Project at UPenn
Fall 2014
MEAM 302: Fluid Mechanics is notoriously tough, so when the professor gave my class an opportunity to get some extra credit for doing an independent, fluids-related photography project, I jumped at the chance. Flow patterns are beautiful, and I was interested in trying to develop a more accessible flow visualization method than the traditional smoke-in-wind-tunnel approach.
The technique makes use of Hele-Shaw flow to visualize fluid flow in two dimensions. I used a shallow rectangular open-top channel with mounting holes for various 2D objects, a water source, and an india ink dye solution to visualize the flow patterns. Because the flow is so shallow, the velocity gradient in the Z direction is very steep, and the velocity profiles in the X-Y plane can be made effectively uniform relative to the size of the obstacle. The Reynolds number for the channel flow is approximately 8x10E4, so the flow is turbulent.
FLOW CHANNEL
BOUNDARY LAYER (RECTANGLE SIDE)
Visualizations like this help us gain intuition about fluid flow, guide experiment and design choices, and even check the results of computer flow models. The method I used to expose the flow patterns was a simple and elegant way to visualize the fluid flow around different 2D shapes. My professor agreed and ended up keeping the setup to use for in-class demos.