CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > ANSYS > FLUENT

Inducer+centrifugal impeller

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Search this Thread Display Modes
Old   October 10, 2011, 11:01
Default Inducer+centrifugal impeller
New Member
Join Date: Mar 2009
Posts: 1
Rep Power: 0
marcelvduarte is on a distinguished road
Hi everyone,

Last months, I designed a high-speed centrifugal pump that is composed by an inducer +
centrifugal pump + volute + conical diffuser in this flow sequence.
It rotates 30000rpm. This is very common in turbopumps of Liquid Rocket Engines.

In my case I just have to simulate the centrifugal pump. Of course it is not the ideal solution. It must simulate the inducer together because the rotational component of velocity before the inlet of centrifugal pump. Any way I did the wrong way. The centrifugal pump was designed considering the component velocity.

In this simulation using Fluent v6.3, I considered the flow axially the inlet plane of centrifugal pump and without volute and conical diffuser, just an extension at inlet and outlet to improve the convergence of solution.
I know the volumetric flow and inlet pressure and the required outlet pressure at design condition.
My boundary conditions were inlet pressure at inlet and outlet pressure at outlet. Instead of it, if I considered mass flow inlet, the solution gave me wrong inlet pressure.

I got good convergence solution using steady, k-epsilon, SIMPLE, double-precision and hybrid mesh (boundary layer + tet) for large volumetric flow (overload conditon). Decreasing the volumetric flow (the Fluent gave the mass flow rate) I could not obtain convergence of solution. The pressure fluctuates too much. I think of that is the presence of unsteady phenomena rotating stall.

So if anyone can help, my questions are:
  1. my boundary conditions (inlet pressure and outlet pressure) are the correct decisions?
  2. is it really necessary to simulate the inducer with the centrifugal pump in my case?
  3. is it is necessary to simulate with volute?
  4. for steady, kappa-epsilon I can conclude that the problem is the rotating stall?
  5. unsteady solution will predict better the rotating stall?


marcelvduarte is offline   Reply With Quote

Old   October 11, 2011, 00:45
New Member
sabin's Avatar
sabin mathew
Join Date: Sep 2011
Location: Mumbai
Posts: 18
Rep Power: 14
sabin is on a distinguished road
Send a message via Skype™ to sabin
I think you cannot avoid inducer from the problem, since avoiding it will give wrong boundary condition to rest of CV.

In my opinion right boundary condition would be mass flow rate at inlet and pressure at outlet.

You need not go for unsteady formulation , instead you can try steady state in 'Moving Reference Frame' technique.

Sabin Mathew
sabin is offline   Reply With Quote


centrifugal pump, convergence, fluent, inducer

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
[ICEM] Meshing Centrifugal Impeller Bellmo ANSYS Meshing & Geometry 8 November 27, 2018 13:02
Centrifugal Pump Impeller design invincible328 Main CFD Forum 27 September 21, 2014 10:59
[ICEM] Meshing a centrifugal compressor impeller Mitpostdoc ANSYS Meshing & Geometry 8 February 25, 2011 10:51
[GAMBIT] influence between angle in impeller blade and centrifugal pump performance barak182 ANSYS Meshing & Geometry 2 August 18, 2010 03:07
centrifugal compressor impeller with splitter blad deepesh nanda Main CFD Forum 2 October 18, 2004 11:13

All times are GMT -4. The time now is 17:07.