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drcsm March 18, 2015 07:35

Lobe pump
 
Dear all,

I am trying to solve a problem of lobe pump. for devlopement i used immersed solid method for both the lobes.

i am facing problem in.

1. In giving rotation to both the lobes as their rotation axis is not global axis.
2. If use two point method than how to locate those two points?
3. I have selected mass flow inlet and static pressure outlet with symmetry as boundary condition.
4. While solving problem my solver ges excited with " non zero exit error-2".

Guide me how to proceed with or without immerged body problem.

thanks.

ghorrocks March 18, 2015 18:22

Have you done the CFX tutorial examples? There is an example of exactly this sort of simulation.

Have a think about whether a mass flow inlet is appropriate. I would have thought a pressure inlet (or opening) would be more appropriate, as the flow is likely to be a bit pulsating.

drcsm March 19, 2015 05:17

Dear sir,

I think yiu are right but i am facing problem at the innitial stage only in terms of defining rotation axis for both the lobes... can you please guide how to locate he rotation axis which is other than global axis?

xiashang8898 March 31, 2015 04:40

hi
 
Dear sir,

I think wo do the same thing, my job is about a helical gear pump, if you join the QQ group (i built it for this reason) 337969380 , i think we will have a good discussion, or you can send me email 619313616@qq.com ,i hope we'll have a good talk!

Jan Smedseng April 23, 2015 10:19

Maybe twinmesh can help you
 
Hallo.

If you want to calculate lobe pumps with ANSYS CFX or ANSYS Fluent, I want to recommend the program Twinmesh, developed by CFX Berlin.
www.twinmesh.com

This program allowes you to generate the grids for each timestep and provides the complette setup of your simulation for ANSYS CFX.
The way using different grids will provide much better results as using immersed solids. As the meshes have the same topology, no interpolation between the timesteps is needed.
There are also tutorials for the usage of twinmesh and the calculation of lobe pumps in ANSYS CFX included.

Regards,
Jan Smedseng

xiashang8898 April 23, 2015 22:39

hi
 
Quote:

Originally Posted by Jan Smedseng (Post 543401)
Hallo.

If you want to calculate lobe pumps with ANSYS CFX or ANSYS Fluent, I want to recommend the program Twinmesh, developed by CFX Berlin.
www.twinmesh.com

This program allowes you to generate the grids for each timestep and provides the complette setup of your simulation for ANSYS CFX.
The way using different grids will provide much better results as using immersed solids. As the meshes have the same topology, no interpolation between the timesteps is needed.
There are also tutorials for the usage of twinmesh and the calculation of lobe pumps in ANSYS CFX included.

Regards,
Jan Smedseng

thank your recommendation,i wanted to have a try once ,but i do not have the program,and i am a student ,can not afford such a expensive software,even no matter how i want.

ghorrocks April 23, 2015 22:50

Then the immersed solids approach is likely to be your best path forward. It has limitations which you should be aware of, but is by far the easiest way of modelling these sort of pumps.

ghoshi1983 July 11, 2017 12:48

Following is the lobe pump simulation tutorial for people interested in such simulations: http://fetchcfd.com/view-project/730


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