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.

A very basic question

Please login with a confirmed email address before reporting spam

Hi all,

I'm just getting to grips with COMSOL (version 5.0) and I've been following through this tutorial to try and get the hang of the modelling environment.

implicit.che.utah.edu/Teaching/6353/Introduction_to_Comsol.pptx

I'm having a little bother working out where I'm going wrong and would appreciate a few pointers to get me going. I've followed the steps through to the point of computing, but when I try to run the model I get an error saying

Unknown function or operator.
- Name: step1
- Feature: Time-Dependent Solver 1 (sol1/t1)

which I've traced back to the point at which I've defined the inlet velocity but beyond that I'm lost. Is this a predefined function for a previous version of comsol or do I need to define it somewhere else.

any help would be much appreciated.

cheers,

Jamie

2 Replies Last Post 8 mai 2015, 05:42 UTC−4
Jeff Hiller COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 7 mai 2015, 08:27 UTC−4
Hello James,
"step1" is the name COMSOL gives by default to the first step function the user creates in their model (under Global>Definitions>Functions>step), but from a quick look I took at the slides it does not look to me like the author of the slides ever creates such a step function. It looks like the author of the slides forgot to document that part of the model set up. You may want to contact them.

Alternatively, you can find dozens of up to date tutorials with step by step instructions inside the software under File>Application Libraries at version 5.1. In earlier versions, look for "Model Libraries" instead. The flow over a cylinder model in the slides seems to be borrowed from there, but you will find many more.

Best,
Jeff
Hello James, "step1" is the name COMSOL gives by default to the first step function the user creates in their model (under Global>Definitions>Functions>step), but from a quick look I took at the slides it does not look to me like the author of the slides ever creates such a step function. It looks like the author of the slides forgot to document that part of the model set up. You may want to contact them. Alternatively, you can find dozens of up to date tutorials with step by step instructions inside the software under File>Application Libraries at version 5.1. In earlier versions, look for "Model Libraries" instead. The flow over a cylinder model in the slides seems to be borrowed from there, but you will find many more. Best, Jeff

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 8 mai 2015, 05:42 UTC−4
Thanks for a quick response Jeff
Thanks for a quick response Jeff

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.