Negative Total Pressure Loss Coefficient near the casing in axial compressor
 

Hi!
My question is specific to CFX Turbomachinery, axial flow compressor.

I am trying to plot the circumferentially averaged value of total pressure loss (occurred between the stator inlet and stator outlet stations) along the annulus height (from Hub to casing),i.e along the hub to shroud line.

Total Pressure Loss Coefficient= (P03-P02)/(rho*V^2);

But i find that very near to the casing i.e. at nearly 99.5% of annulus height, i find an increase in pressure or a small negative pressure loss coefficient,which means energy is being created,which does not happen within a stator passage.Does it mean that theres an energy transfer/migration from somewhere to the viscous layer nearby the casing region? I donot know how to explain the negative number(rise in total pressure at a single point in the viscous region).The entropy rise is positive at that location , obeying thermodynamics well

Please ,if any one has any idea of where i am going wrong,let me know.
:)

Hi, I am also facing a similar problem at rotor hub, the loss coefficient is coming negative from 0 to .15 span. were you able to find any solution to your problem?