国产在线精品一区二区三区不卡/精品国产一区二区三区四区五区/freezeframe丰满少妇/亚洲国产精品二二三三区/免费无码国产v片在线观看

Laboratory ventilation system
There are two types of ventilation and exhaust systems: 1. Constant volume (CV); 2. Variable air volume (VAV), both systems can be used with separate or assembled piping and blower configurations.

Constant volume exhaust system
Keep the fixed gas displacement without regard to the position of window, the surface speed is controlled by setting some air compensation methods.

Variable air volume exhaust system
To keep fixed surface rate by changing gas displacement to cope with change of window. A VAV system is more sophisticated and requires more hardware, but it is useful in a particular environment.
Can be designed and produced at the request of clients.