Xin Feng Mini Lesson--- Causes of Low Output and Efficiency in Centrifugal Fans

Low output and efficiency in centrifugal fans are common issues stemming from multiple factors.

These may include design or manufacturing flaws, or relate to equipment operation and maintenance.

Since design and manufacturing issues are complex, we will primarily analyze factors tied to fan operation and maintenance.

As is well known, every centrifugal fan has its own specified operating range. Running within the design conditions allows for higher operational efficiency.

However, in actual operation, selected parameters may be too low or too high. Factors such as duct resistance and changes in medium temperature can lead to equipment capacity being either too large or too small. This results in insufficient fan output, failing to meet the ventilation requirements of the boiler.

Conversely, if the centrifugal fan's output is excessively high, it may operate at low load, actually increasing losses and reducing efficiency.

Therefore, improperly set operating parameters or operation outside the design point are the primary factors causing low output and efficiency.

Secondly, in practical applications, an unreasonable design of connecting ducts can lead to low output and efficiency of the centrifugal fan.

For example, in a high-capacity fan, failure to install guide vanes on the inlet elbow significantly increases pressure loss compared to an equipped design.

Properly designed duct sections can minimize such resistance losses.

Beyond these factors, if the gas flow direction within the inlet duct opposes the impeller's rotation, efficiency will also drop significantly.

In such cases, repositioning the duct to align the inlet gas flow direction with the fan's rotation will improve efficiency.