Slip coefficient by AUNGIER/ WIESNER

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Slip coefficient by AUNGIER/ WIESNER

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Outflow (slip) coefficient γ is defined for the decreased energy transmission:



The cu-difference is called slip velocity.


The smaller the outflow coefficient, the higher the deviation of flow compared to the direction given by blade.


Aungier adjusted Wiesner's original empirical equation for the estimation of outflow coefficient:


The limiting radius ratio εLim is given by:


The slip factor is corrected for radius ratios ε = r/r2 >  εLim with:


[ Compressors only ]

The model is further adjusted in case it is applied to splitter blades. Then the number of blades in the above equation is corrected by the relative splitter blade length with respect to the main blade length.


Circumferential component of blade congruent flow can be calculated as follows: