The Principle and Function of Wind Tunnels

A wind tunnel lab is a tubular experimental facility that artificially generates and controls airflow to simulate the flow of gas around aircraft or physical objects. It enables the measurement of airflow effects on these objects and the observation of physical phenomena, serving as one of the most common and effective tools for conducting aerodynamic experiments. A wind tunnel primarily consists of the tunnel body, the drive system, and the measurement and control system, with the configuration of each component varying depending on the type of wind tunnel.
Due to their excellent controllability and high repeatability, wind tunnels are now widely used for testing in automotive aerodynamics and wind engineering. Applications include structural wind loads and vibrations, building ventilation, air pollution, wind power generation, environmental wind fields, flow conditions in complex terrain, and the effectiveness of windbreak structures. These problems can all be addressed by applying the principle of geometric similarity: scaled models of terrain and objects are placed in a wind tunnel, and then instruments are used to measure the wind force or wind speed acting on the models. Some studies have also indicated that wind tunnel test results closely resemble observations from actual wind fields, making wind tunnel testing the most commonly used method for investigating numerous wind engineering problems. Wind tunnel test data can also be used to validate the effectiveness of numerical models and identify optimal model parameters.