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.

Heat Pulse - Laminar Flow

Please login with a confirmed email address before reporting spam

Hi,

I have a relatively simple problem; however, I'm finding it hard to find the solution.

I have laminar flow in a pipe and want to have a pulse of heat at the inlet for 0.5 seconds, I then want to monitor this pulse for ten seconds with the pulse switched off.

I can not find a way to generate this pulse and have tried to do this through generating a pulse in definitions; however, am not able to implement this after into the heat transfer in fluids physics.

Help would be greatly appreciated.

Thanks

1 Reply Last Post 2017年6月23日 GMT-4 02:21

Please login with a confirmed email address before reporting spam

Posted: 7 years ago 2017年6月23日 GMT-4 02:21
Updated: 7 years ago 2017年6月23日 GMT-4 02:22
Thomas,

You may use a rectangular function.

1) Go to model1 -> definition -> functions -> rectangle
change the lower and upper limits as you desire (i.e. 0 s and 0.5 s).

2) Define a heat flux at the inlet as: Q_inlet*rect1(t[1/s])

To monitor the outlet, you may integrate the total heat flux (ht.ntflux) at the outlet after you solved the problem and plot it with time.

Amin,
Thomas, You may use a rectangular function. 1) Go to model1 -> definition -> functions -> rectangle change the lower and upper limits as you desire (i.e. 0 s and 0.5 s). 2) Define a heat flux at the inlet as: Q_inlet*rect1(t[1/s]) To monitor the outlet, you may integrate the total heat flux (ht.ntflux) at the outlet after you solved the problem and plot it with time. Amin,

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.