Selection of higher efficiency, smaller fan, adjust the scope of the larger fan, to meet the system acceptable performance, efficiency and quality requirements.

      Fan operating point, should be selected in the vicinity of the effective point of the fan to ensure stable operation, to avoid fan work in the surge zone.

      To reduce noise, you must reduce the fan speed, choose a larger fan.

      VAV system fan, air volume pressure should be run for a long time part of the load conditions selected.

      Excessive fan selection, often the fan running in the small air volume area, the fan import and export pressure difference, will cause the operation of instability and noise pulsation, issued a higher noise.

      Small fan selection, will cause the fan speed increases, the air leaves the blade when there is a higher speed, will produce higher noise.

      The average speed of the fan outlet is usually 10-15 M / s

      Forward multi-wing fan: with low speed, light structure, low noise, good speed performance and low price and other characteristics, when the design of air flow and pressure is small, or large air pressure should be preferred when the forward fan.

      Backward fan: with high efficiency, low noise, high pressure and strong structure, and so on, when the design of the fan pressure should be preferred when the rear fan.

      Shellless fan: When the pipe network needs a flexible export location, the need to reduce the pipe outlet noise, or pipe network in the future may change the occasion should be preferred.