Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

How does COMSOL treat the space around the geometry

Please login with a confirmed email address before reporting spam


Dear all

I have a model, in which a cylindrical geometry is in contact with the room temperature. I'd like to know the final temperature distribution in between the two walls of the cylinder.
So, my question is whether I should set both the initial temperatur and the wall's temperature to 20°C or only the initial temperature?
Generally, how will COMSOL treat the surrounding environment, which my geometry is in contact with? because I only like to make it understand that my geometry is functioning in the room temperature.
--
Regards

1 Reply Last Post 27.09.2016, 15:02 GMT-4
Robert Koslover Certified Consultant

Please login with a confirmed email address before reporting spam

Posted: 8 years ago 27.09.2016, 15:02 GMT-4
If the resulting distribution or flow of heat within the surrounding volume itself is not of interest to you, then you may be able to represent that surrounding volume by a boundary condition on your object. The choice of boundary condition depends on what you need to represent. For example, for an object immersed in a constant-temperature, high thermal conductivity heat reservoir, you might want to specify a fixed temperature (i.e., the temperature of the heat reservoir) on the boundary of your object. On the other hand, for an object surrounded by a thermally insulating environment, you might want to specify a thermal insulation boundary condition. For conditions in-between those extremes, you'll need to come up with something else that is realistic, or you'll risk getting the wrong answer. In that case, you may need to include at least some of that surrounding volume in your computation space, and then surround that larger volume with an appropriate boundary condition.
If the resulting distribution or flow of heat within the surrounding volume itself is not of interest to you, then you may be able to represent that surrounding volume by a boundary condition on your object. The choice of boundary condition depends on what you need to represent. For example, for an object immersed in a constant-temperature, high thermal conductivity heat reservoir, you might want to specify a fixed temperature (i.e., the temperature of the heat reservoir) on the boundary of your object. On the other hand, for an object surrounded by a thermally insulating environment, you might want to specify a thermal insulation boundary condition. For conditions in-between those extremes, you'll need to come up with something else that is realistic, or you'll risk getting the wrong answer. In that case, you may need to include at least some of that surrounding volume in your computation space, and then surround that larger volume with an appropriate boundary condition.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.