<< Click to Display Table of Contents >> Slip coefficient by PFLEIDERER 

Reduced energy transmission is expressed by decreased output coefficient p:
This coefficient can be empirically calculated in dependence of experience number ψ':
static moment from leading to trailing edge
experience number
experience number a: 


Centrifugal impeller 
with guided vanes 
a = 0.6 
with volute 
a = 0.65…0.85 

with plain diffusor 
a = 0.85…1.0 

Mixed flow/axial impeller 
a = 1.0 …1.2 

(the numbers are valid for sufficiently high Re; ψ’ strongly grows with small Re) 
More descriptive is the decreased output factor kL:
(kL=1: for flow congruent to blade)
Circumferential component of the flow, which is congruent to blade, can be calculated as follows:
Now the outflow (slip) coefficient γ according to Wiesner can be calculated: