Advancements in Experimental Aerodynamics: Automating Analog Wind Tunnels with Digital Capabilities

Abstract

This study presents a new approach for automating an analogue wind tunnel and modifying into a digital reading system with the aid of advanced technologies and algorithms. The study establishes a procedure to determine the efficiency and accuracy of the modified wind tunnel by comparing theoretical drag forces to experimental forces under different air speeds. Test of drag forces on an improved system cylindrical and cuboidal models. In the experimental process, models were mounted on a load cell sensor in the test section where drag forces are determined for prechosen free stream velocities. Drag forces are compared theoretically and experimentally, and they agree with expected trends in drag as function of velocity that arises from fundamental aerodynamic theory. Sensitivity analysis was demonstrated to test the measuring device sensitivity and confirms the major difference between theoretical and experimental magnifications of sensitivity in the cylindrical and cuboidal models. The mean sensitivity magnifications of 49.5 Ns/m and 222.5 Ns/m for cylindrical and cuboidal test models respectively show that the experimental values in the digitalized measuring equipment were significantly amplified, in line with the advantages of digitalized measuring devices. Statistical tests, founded on Mean Squared Error (MSE) and Average Sensitivity, were performed to analyse the differences between theoretical and experimental data. The analysis indicates that the modified wind tunnel equipment is moderately sensitive in the case of cylindrical model, tracing the general trend of the system without causing large errors. However, the cuboidal model possesses higher sensitivity with the ability to amplify noise or measurement error, which makes a significant difference between the experimental and theoretical results. Overall, this study presents practical insight into how the modified wind tunnel operates and its limitations, which can be used to further develop the wind tunnel to improve its performance and considered within experimental aerodynamics.