Flow analysis of container containing a perforated pipe


#1

Hello,
I am currently working on a project involving analysis of a container which has a perforated pipe and various chambers in it. I wish to apply pressure at both the inlets and outlets and see the variation in flow throughout the container. Currently i am facing difficulty in meshing it as it involves a perforated pipe in it i am unable to mesh it. Can anyone suggest me what all changes are required in my current CAD for the same .
Thank you.
https://www.simscale.com/projects/omkar/cfd_analysis_of_muffler_1_1/


#2

Hi @omkar and thanks for posting your issue here in the forum!

I will look at your project later on and see what we can optimize in your case.

Cheers and all the best!

Jousef


#3

Hi @omkar!

Coming back to you with a small delay. I have created a first simulation with boundary conditions that can be adapted by you. Make sure you run the simulation a bit longer as the simulation is not converged! Please take into account a higher inlet pressure as well as the back pressure (if you even want to investigate that).

Let me know if you need any help or have any questions in general.

Best,

Jousef


#4

Please send me the link of the simulation which you have done in the above message.


#5

You should have received a message @omkar!

Cheers!

Jousef


#6

You mentioned about monitoring of the back pressure can you suggest a way to do that ?


#7

Hi @omkar!

It was just an idea if you want to take care of that pressure inside the simulation. Back pressure is defined like an “extra static pressure” exerted by muffler in an engine through restriction in flow of exhaust gases. The higher the back pressure the less efficiency, more fuel consumption, overheating you might have (can also cause shutdown of an engine if the exhaust is poorly designed). We always want the lowest pressure possible in the branch of the manifold because when the exhaust valve opens it tries to push out old exhaust gas allowing more oxygen to be drawn into the cylinder on the next intake stroke. There are some good papers I found taking into account the perforations of the muffler (and the back pressure also being influenced by these perforations).

  1. Backpressure Study in an Exhause

  2. CFD ANALYSIS OF BACK PRESSURE OF REACTIVE MUFFLER

Those two papers should be a good start to delve into this subject. I mean if this is not relevant for your studies and the back pressure is negligible in the first place do not worry too much about it but I thought it is good to know about it.

Best,

Jousef


#8

I am getting an error stating fatal input/ ouput error when I do my simulation run. Please suggest a solution for it.
https://www.simscale.com/projects/omkar/muffler_4-2_2/


#9

Having a look at it @omkar. :+1:


#10

Hi @omkar!

You may now proceed with your simulations :+1: The issue has been resolved by our engineers.

Sorry for the lost productivity again. Please let me know if I can do anything for you.

Cheers!

Jousef


#11

Thanks @jousefm.


#12

Can you suggest a way to measure the exact value of pressure at outlet of muffler from cfd analysis??


#13

Hi @omkar!

You can create a Result Control item and use Area average for instance at the inlet as well as the outlet to either see the pressure drop or just the pressure at the specific surfaces you have selected. I am currently running an example to show you what I have done and share it with you later on. Hope that’s fine!

Cheers!

Jousef


#14

Sure :+1:t2: @jousefm


#15

Thank you :+1:t2: @jousefm