Mathematical Model Of Closed-Loop Aerodynamic Tube

This study explores a closed‑loop aerodynamic tube that recirculates air to create stable, repeatable flow conditions in a laboratory setting. In this configuration, a fan continuously drives air through a closed duct, past a central test section where measurements and experiments are carried out, and then back to the fan inlet. The closed loop reduces the impact of ambient disturbances and helps maintain the desired flow with relatively modest energy use. The test section is designed with a nearly constant cross‑sectional area so that the velocity field is as uniform as possible, which simplifies both instrumentation and data interpretation. Upstream, a contraction accelerates and conditions the flow, while downstream diffusers and curved ducts gently slow and redirect the air, preserving flow quality as it recirculates. Taken together, these features provide a compact and efficient platform for high‑fidelity aerodynamic testing and control‑oriented studies of internal flows.