Active flow control is a technique used in fluid dynamics to manipulate the flow of air or liquid around objects, such as aircraft or automobiles. By using devices like sensors and actuators, engineers can adjust the flow in real-time, improving performance and efficiency. This can lead to reduced drag, enhanced lift, or better cooling in various applications. The primary goal of active flow control is to optimize the interaction between the fluid and the surface it flows over. This technology can be applied in various fields, including aerospace, automotive engineering, and HVAC systems, to achieve better aerodynamic or hydrodynamic performance.