Air volume of centrifugal blower
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I have a centrifugal blower; the nameplate indicates an outlet pressure of 76,000 Pa and an air volume of 177 m3/min. Could the air volume of the blower be adjusted to a lower level? If the device doesn’t require that much air flow, can it be controlled at around 100/min? If the air volume is outside the specified range, will this cause surge in the fan? Please share your thoughts; extra points for that
Unlike centrifugal air compressors, blowers have very low pressure but high volume flow. If it is necessary to control the air volume, it is recommended to change the size of the pulley or install an inverter.
Such fans also require characteristic curves; if the air intake volume is low enough, surge will occur at a constant outlet pressure. Therefore, such a minimum load test should be conducted during testing or during idle times in production. The method involves maintaining a constant outlet pressure, while reducing the air flow at the inlet or lowering the rotational speed. When low-frequency vibration sounds occur due to the airflow, this level of air intake (or rotational speed) represents the minimum load for that equipment. Under normal operation, it is necessary to increase the air flow appropriately to eliminate these low-frequency sounds, and this amount constitutes the minimum operational level allowed.