Discussion Groups

Simulation Mechanical and Multiphysics

Reply
Active Contributor
Sultan9009
Posts: 34
Registered: ‎06-19-2012

Steady coupled thermal and fluid flow help

122 Views, 2 Replies
08-01-2012 09:32 AM

I need help with this analysis because every time, I run simulation, the results are always zero for velocity, calculated temperature, and I not getting any results for pressure. I also want to know if I will be able to have the shaft have a constraint of rotated frame. I know the velocity and initial temperature for the inlet but know nothing for the outlet.  I try uploading a ach file, but the file is too big

 

I have designed a water heater. I need to run a thermal and fluid analysis on the water heater. The water heater is driven by a motor through a gear ratio. There is a shaft rotating inside the water heater. It rotating at 1760 rpm. The initial conditons I know is, the initial temperature at inlet which is 30 degree celius. I also know the velocity at the inlet which is 1973.5mm/s. I want to perform, a steady fluid flow, steady thermal flow, and steady coupled fluid and thermal flow analysis. Also, when I am running the fluid flow analysis, I am using the internal volume of the water heater and setting it to water. But I want to use the rotating shaft, which is causing a increase in pressure and velocity of the water inside the water heater, however, I getting illegal elements and it is not meshing because the rotating shaft is not a fluid but a solid. Also I am getting the results as zero. But I checked and loads are not zero. I put a initial temperature and velocity at the inlet. I know the the conditions of the water, which I consider to be the internal volume. The outer case, I do not know any information. So i placed a 30 degree celius load on the surface of the inlet, and a velocity at the outlet.

 

Please use plain text.
Employee
INACTIVE_AstroJohn
Posts: 492
Registered: ‎03-25-2010

Re: Steady coupled thermal and fluid flow help

08-01-2012 01:43 PM in reply to: Sultan9009

Hi Sultan,

 

Sorry, but I do not think anyone will be able to solve the problem based on the written description along. I think we will need a model. Here are some ideas that come to mind:

 

  1. Perhaps the problem can be reproduced on a smaller model. It would not even need to be the "real design", just include all of the same loads and other setup.
  2. To reduce the size of the archive, you can review the suggestions on the thread "Create, Post, or Provide an Archive of your model".
  3. Contact technical support. I am sure that they have ways of obtaining models much larger than what can be posted to the Discussion Group. Support can be obtained through the Subscription Center or as described below.

You can access the Autodesk Subscription Center by accessing the following link:

http://subscription.autodesk.com/

You will need to log on using your Autodesk user id and password. From within the subscription center, you will be able to view past support issues, enter comments and open new support cases.

 

 

 

Sincerely,
John Holtz, P.E.
Senior User Experience Designer, Simulation
Autodesk, Inc.

Current version of Mechanical & Multiphysics: 2013 SP1 (2013.01.00.0012 28-Jun-2012)
Please use plain text.
Active Contributor
Sultan9009
Posts: 34
Registered: ‎06-19-2012

Re: Steady coupled thermal and fluid flow help

08-01-2012 05:21 PM in reply to: Sultan9009

Can I place my model on dropbox? I needed help with a model before and Joey X helped me, he was able to get to my model by going to my dropbox.

Please use plain text.