Abstract：

 The louver damper is a common basic device in HVAC engineering, its technical principle is to realize the opening and closing and regulating function by changing the angle of the shutter. Now, the technology is diversified to achieve the same function, such as flexible materials can also be used as wind blocking material, then the flexible air damper is derived. Based on the principle of louver damper, analyses the functional requirements of air damper.  Describes the characteristics of flexible air damper in effective ventilation area and tightness performance from the aspects of structural design of air damper and the use of the wind blocking material, which provides an alternative way for improving the traditional process principle of air damper.