Passive Flow Control refers to methods used to manage the movement of fluids or gases without the need for active mechanical systems. This approach often relies on natural forces, such as gravity or pressure differences, to direct flow. Examples include the design of channels, weirs, and spillways that guide water in a controlled manner. This technique is commonly used in various fields, including civil engineering and environmental management. By utilizing the natural characteristics of materials and landscapes, passive flow control can reduce energy consumption and maintenance costs while effectively managing resources like water and air.