Mixing tank impeller

Onicon · April 17, 2014, 17:29

Hello. I am trying to model a mixing tank with a single impeller. I am using a rotating reference frame, where I've created a cylindrical rotating fluid around the impeller and defined its rotation.

The problem I'm having is that, when run as steady state, the non-rotating fluid hardly seems affected by the rotating fluid (which in turn doesn't seem affected by the impeller). I've tried different impeller sizes/shapes/blades, but it hardly seems to have an affect on the flow, it mostly just looks like a rotating cylinder of fluid.

In a 1000L mixing tank, I'm seeing very slow velocities away from the rotating fluid zone, 0.01 - 0.10 ft/s, with the rotating fluid moving at 200rpm. I have run the mixing tank in person, and clearly there is more activity irl.

Any thoughts on what I'm missing?

Natali · March 24, 2015, 03:43

Hi, Onicon. I have the same problem as you. Have you decided this problem? I have two parts. One part is a rotating cylinder with emptiness inside in the form of mixer. And the second part is square tank, that surrounds rotating frame.

April 17, 2014, 17:29	Mixing tank impeller	#1
Onicon New Member JK Join Date: Apr 2014 Location: MA Posts: 1 Rep Power: 0	Hello. I am trying to model a mixing tank with a single impeller. I am using a rotating reference frame, where I've created a cylindrical rotating fluid around the impeller and defined its rotation. The problem I'm having is that, when run as steady state, the non-rotating fluid hardly seems affected by the rotating fluid (which in turn doesn't seem affected by the impeller). I've tried different impeller sizes/shapes/blades, but it hardly seems to have an affect on the flow, it mostly just looks like a rotating cylinder of fluid. In a 1000L mixing tank, I'm seeing very slow velocities away from the rotating fluid zone, 0.01 - 0.10 ft/s, with the rotating fluid moving at 200rpm. I have run the mixing tank in person, and clearly there is more activity irl. Any thoughts on what I'm missing? Last edited by Onicon; April 18, 2014 at 12:44.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[ICEM] Tutorial of a mixing time tank equipped with an impeller	Alex69	ANSYS Meshing & Geometry	1	July 18, 2013 04:24
how to start for modelling n meshing a mixing tank with impeller	jeevan	ANSYS Meshing & Geometry	9	July 16, 2013 08:06
3D mixing tank using MRF/SRF	cfd_confuse	FLUENT	0	October 2, 2010 04:46
What method use to modelate a side-entry impeller in a large scale mixing tank?	fcabrales	Main CFD Forum	0	January 29, 2010 15:24
To determine mixing tank with anchor impeller	p prajapati	FLUENT	1	December 12, 2007 16:27

March 24, 2015, 03:43		#2
Natali New Member Nataliia Tatyanko Join Date: Aug 2012 Posts: 3 Rep Power: 14	Hi, Onicon. I have the same problem as you. Have you decided this problem? I have two parts. One part is a rotating cylinder with emptiness inside in the form of mixer. And the second part is square tank, that surrounds rotating frame.