Designing Hydrogen Bubble Flow Visualization for Aerodynamics Experiments
Experimental Study of Thin and Thick Airfoils at Low Reynolds Numbers

Google “drone crashes,” and you’ll get a plethora of hits—videos, databases, news stories and more. It seems the popular unmanned aerial vehicles, commercial and amateur alike, have an unfortunate tendency to crash, especially if the wind changes direction suddenly, and Vibhav Durgesh wants to figure out why. Very little research has been conducted with these aircraft, but the key may lie in the Reynolds number of the airfoils, or wings, which basically measures how fast the air flows over the wings when the drone is flying. The higher the Reynolds number, the faster the airflow. A commercial airliner, for example, has a significantly higher Reynolds number than, say, a drone, and is considerably more stable. To determine the aerodynamic characteristic of lift in thick and thin airfoils and at different angles of attack, Durgesh enlisted the help of an especially dedicated AIMS2 student to design and then run a series of 36 experiments using CSUN’s low-speed flow visualization water tunnel. Each repetition required the student to remain in the lab for 20 hours at a time. The results were presented at the American Institute of Aeronautics and Astronautics SciTech 2016 conference in San Diego in January and attracted a great deal of interest from the audience. “It started as a very small project and grew to be big and had a lot of impact,” Durgesh says.