Design and testing of an affordable desktop wind tunnel

Abstract: Wind tunnels are a key source of data collection, but their cost and size can be a significant obstacle to their acquisition and usage, especially for applications such as instrument calibration, instruction, or in-class demonstrations. Here we propose a design for a cost-effective, desktop wind tunnel. This design takes advantage of readily available, inexpensive materials. Special consideration was taken to allow the wind tunnel to be serviceable, as well as giving the operator the ability to change key features without a complete redesign. There are three main sections, the first being a fan enclosure, which holds seven ducted fans in a hexagonal array. The second section holds honeycomb flow straighteners, and provides an enclosed volume suitable for larger, lower-speed experiments. The third section is a contraction, terminating in a 2in x 2in, higher-speed square section. The wind tunnel has a footprint of approximately 13.5in x 5.5in, making it small enough to be portable and to fit on a desk. An off-the-shelf masked stereolithography apparatus (MSLA) 3D printer was used to prepare the parts. This allows the wind tunnel to be built for under \$500; even including the cost of a 3D printer, the overall cost remains under \$1,000. This design is able to produce flow at up to 44.1 m/s, enabling a variety of aerodynamic demonstrations.