Backward Inclined Fan Vs Forward Curved

The modern forward curved blades are designed with a scroll housing.

Backward inclined fan vs forward curved.

With a backward curved impeller the air exits in a radial direction whereas with a forward curved the air exits tangentially from the circumference of the fan. Forward curved fans are usually limited in size which means the top end flowrate is lower than axial or backward curved feel free to browse some of the why use a xx fan articles i have previouusly posted for further information. A forward curved centrifugal fan is characterised by its cylindrical shape and lots of small blades on the circumference of the impeller. Our fan rotors are balanced to ansi standards and our finite element analysis and other advanced testing processes make sure that your backward inclined fan boasts a stable design and accurate performance.

Another important design feature is the position of the motor. The backward inclined centrifugal fans offer three standard blade types flat single thickness curved single thickness and curved airfoil. They often vibrate more than backward curved centrifugal fans as well and aren t as strong structurally. Curve dips to left of peak pressure.

In most cases these fans are designed with external motors. Backward inclined the performance of the backward inclined wheel is similar to the forward curve however bi fans tend to be non overloading meaning their fan curves do not tend to increase hp as static pressure changes but cfm falls off. The forward curved impeller is therefore much quieter than the backward curved impeller and due to the higher number of blades gives a noise spectrum with much wider bandwidth and therefore lower energy in any part of the spectrum when compared to the backward curved impeller. 1 forward curved blades curve in the direction of the fan wheel s rotation on the other hand backward curved blades curve against the direction of the fan wheel s rotation.

Power rises continually toward free delivery. Pressure curve less steep than that of backward curved fans. On the other hand those with backward curved blades are basically free wheeling fans. 2 forward curved blades provide a low noise level comparitive to backward curved blades because backward curved blades have high speed relatively to forward curved blades for same capacity range.

Backward inclined fans at processbarron we can custom fabricate a new or a replacement backward inclined flat fan out of a wide variety of materials like heavy duty steel or exotic alloys. Motor selection must take this into account. In the example shown below the fan rotates in a clockwise direction. Do not rate fan in the pressure curve dip to the left of peak pressure.

This reduces the level of noise. Flatter pressure curve and lower efficiency than the airfoil fan backward curved fan and backward inclined fan. They produce relatively medium to high airflow at static pressures.