EBM离心风机蜗壳尺寸说明
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Noise / efficiency curve
Operating range
Middle part of air performance curve:-maximum efficiency -minimum noise
-higher performance density than with the backward curved centrifugal fan
To the right and left of the middle part of the air performance curve:-reduced efficiency -increasing noise
The optimal operative range of the blower is shaded in green in the curve given here.
The forward curved centrifugal impeller must always be operated inside a scroll housing.
A dual inlet centrifugal blower shows the same behaviour as two single inlet blowers operated in parallel:with size,speed and pressure being identical,double the air flow is achieved.Dimensioning of the scroll
The dimensions of a typical scroll can be calculated with the following formulae,subject to the impeller diameter D:
A =1,062 ·D
B =0,992 ·D
C =0,922 ·D
D =0,853 ·D
E =0,784 ·D
F =0,715 ·D G
=0,646 ·D H =0,612 ·D J =0,720 · D K =0,689 ·D R =0,073 ·D
Adjusting the dimensions to diminished mounting spaces is possible.