Interpretation of Vibration Phenomena in Wear-Resistant High-Pressure Centrifugal Fan Ducts

Interpretation of Vibration Phenomena in Wear-Resistant High-Pressure Centrifugal Fan Ducts

Generally, vibration in the air ducts of wear-resistant high-pressure centrifugal fans may be caused by pressure pulsations and turbulent airflow within the duct system.

Such vibration phenomena can manifest in various forms, including oscillations due to Berault vortex pulsations.

This situation primarily stems from an unreasonable structural design at the inlet of the wear-resistant high-pressure centrifugal fan.

In practical terms, the key characteristics of this vibration phenomenon can be summarized as follows: Pressure waves in wear-resistant high-pressure centrifugal fans are often irregular, with amplitude increasing as flow rate rises.

In the second scenario, vibration is triggered by localized vortices within the duct.

This situation primarily results from improper design of air duct components like the Erbo and diffuser, leading to impaired airflow. Consequently, local vortices or turbulent flow disturbances within the duct cause pressure pulsations in the airflow, thereby inducing noise and vibration in the ductwork.

Such vibration exhibits no regular pattern, with amplitude increasing as the load on the wear-resistant high-pressure centrifugal fan grows.

Another scenario involves vibrations arising from insufficient rigidity in the casing and duct walls.

The characteristic of this vibration is higher amplitude at locations with weaker rigidity.

Beyond the aforementioned phenomena, another condition commonly referred to as rotational stall may occur.

Vibrations caused by this condition exhibit the following characteristics:

1. Vibrating sections are predominantly located in the inlet plenum and outlet ductwork of the wear-resistant high-pressure centrifugal fan.

2. Vibration primarily occurs in fans with inlet weirs and backward-curved blades. When this occurs, the actual flow rate and pressure of the wear-resistant high-pressure centrifugal fan unit exhibit noticeable pulsations.

Generally, the opening degree of the wear-resistant high-pressure centrifugal fan damper causes strong vibration between 0 and 30 degrees. Beyond 30 degrees, vibration decreases to normal levels.