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## Please help me find how to achieve this function.

Posted 03/12/2012, 23:45 GMT-05:00 Heat Transfer & Phase Change, Modeling Tools, Parameters, Variables, & Functions, Results & Visualization, Studies & Solvers 4 Replies

It seems to be a simple problem but I can't figure out how to make it.

Description: a 2d transient model of a square is built, the left, bottom, and right side is thermal insulation and the top side is under a convective cooling under air(300K). The domain has an initial temperature at 350K. Now I need my top side has a temperature at 400K for 15 seconds and then moved away to observe the cooling down by air. I tried two ways but none of them available.

1. In heat transfer module, I add a equation in "Temperature": 400*(t>=0[s] && t<=15[s])+(t>15[s]). After simulation, the temperature cool down rapidly to nearly 20K after 15s, and it seems that the temeprature of top side has turn to 0K after 15s.

2. In the study part, I separate the step into two steps(first is 0s-15s, and second is 15s-30s). In the second step, the "temperature" part was disabled. After simulation, the solution only provide the part of second step, but not the first step(0-15s).

Please help me find how to achieve this correctly? Thank you in advance.

Description: a 2d transient model of a square is built, the left, bottom, and right side is thermal insulation and the top side is under a convective cooling under air(300K). The domain has an initial temperature at 350K. Now I need my top side has a temperature at 400K for 15 seconds and then moved away to observe the cooling down by air. I tried two ways but none of them available.

1. In heat transfer module, I add a equation in "Temperature": 400*(t>=0[s] && t<=15[s])+(t>15[s]). After simulation, the temperature cool down rapidly to nearly 20K after 15s, and it seems that the temeprature of top side has turn to 0K after 15s.

2. In the study part, I separate the step into two steps(first is 0s-15s, and second is 15s-30s). In the second step, the "temperature" part was disabled. After simulation, the solution only provide the part of second step, but not the first step(0-15s).

Please help me find how to achieve this correctly? Thank you in advance.

4 Replies Last Post 07/12/2012, 02:41 GMT-05:00