Flow Separation in GE frame 9 Compressor CFD simulation

chocolater · October 23, 2017, 14:54

Has anybody simulated GE frame 9 Compressor? I had simulated this 17th stages compressor with the CFX; when I used a coarse mesh with y+=30 and k-w turbulence model, there is no problem in convergence and everything in CFD-POST is fine. But when it comes to simulating with a fine mesh, y+=1 and SST turbulence model; Inlet mass decreases and post-process show a big region of flow separation near the leading edge close to the hub. Can anybody give me any tips?

CFDpal · October 27, 2017, 11:35

Typically, certain flow effects are not captured on coarse mesh. They are smeared over the cell volume. Separation at the hub is a problem. Try to eliminate/isolate the problem and simulate the stage with different boundary conditions (reduce discharge pressure, or mass for example). See if the separation is still present.

Frankly, I do not have experience with that particular frame.

CFDpal

October 23, 2017, 14:54	Flow Separation in GE frame 9 Compressor CFD simulation	#1
chocolater New Member i man Join Date: Feb 2013 Posts: 10 Rep Power: 13	Has anybody simulated GE frame 9 Compressor? I had simulated this 17th stages compressor with the CFX; when I used a coarse mesh with y+=30 and k-w turbulence model, there is no problem in convergence and everything in CFD-POST is fine. But when it comes to simulating with a fine mesh, y+=1 and SST turbulence model; Inlet mass decreases and post-process show a big region of flow separation near the leading edge close to the hub. Can anybody give me any tips?

October 27, 2017, 11:35		#2
CFDpal New Member CFDpal Join Date: Mar 2017 Location: Boston, MA Posts: 20 Blog Entries: 1 Rep Power: 9	Typically, certain flow effects are not captured on coarse mesh. They are smeared over the cell volume. Separation at the hub is a problem. Try to eliminate/isolate the problem and simulate the stage with different boundary conditions (reduce discharge pressure, or mass for example). See if the separation is still present. Frankly, I do not have experience with that particular frame. CFDpal chocolater likes this.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Which turbulence model is applicable for Plain diffuser flow simulation in openFOAM?	mukut	OpenFOAM Running, Solving & CFD	4	January 30, 2015 08:06
how to get a time-accurate solution in Flow Simulation	drdet	FloEFD, FloWorks & FloTHERM	4	January 20, 2015 07:11
Waterwheel shaped turbine inside a pipe simulation problem	mshahed91	CFX	3	January 10, 2015 11:19
[CFX] Simulation of Flow Separation in a rectangular diffuser - Convergence Problem	anon_b	CFX	11	May 6, 2012 20:16
Differences and functions of Solidworks Simulation and Solidworks Flow Simulation?	alpharays	Main CFD Forum	0	April 19, 2012 03:13