Dear users

In the Fluid Mechanics literature, for example written by Frank M. White in my case, we have a diagram of "flow losses in a gradual conical expansion region". It is the pressure loss curve for the flow in pipes situation. The pipe has a conical expansion and the loss K is clearly obtained from here.

Now my problem is I can't verify any result of K although i have accomplished to do the analysis properly in Fluent. I have made many tries with several conical angles and several inlet velocity values. Just for an example i find K=0,09 although it is K=0,5-0,6 from the diagram in the textbooks.

Do you have any experience on this or do you have any sugestions?

I can send you my model.

I also have the same experience in the simulation of straight circular pipe. The result by K-e model is close to the that of Frank M. White But the The result by RSM model have a big difference though y+~1.

I have used the k-e model. Do you think RSM improves the results? Big difference ı have though.

No, I feel RSM model gives big difference between the simulation and empirical formula, k-e model gives a good result. I don't know the reason.

What was the % error in your study comparing to the literature?

RSM model gives about half of the empirical formula's result.