## General Mechanical

#### How to set up time in transient thermal analysis?

• amando.gallardo
Subscriber

Hello!

I want to simulate a thermal cycling with time depending. Temperature goes: 20°C (12 hrs), 40°C (14 hrs), 80°C (6hrs), -40°C(6 hrs), 40°C(14 hrs) and 20°C(4 hrs).

I know it might be defined through step controls, however I am not pretty sure about the right set up for time.

Could you help me to clarify that please?

Thank you!

• peteroznewman
Subscriber
What is the Initial temperature of the parts? If it is 20C, then step 1 is irrelevant.nANSYS computes in seconds. The 40C is 14 hours = 50,400 seconds.nUnder Analysis Settings, change Auto Time Stepping to On.nInitial Time Step = 500 seconds or about 1%nMinimum Time Step = 50 seconds or about 0.1%nMaximum Time Step = 5000 seconds or about 10%nUse a similar pattern for the other steps.n
• amando.gallardo
Subscriber
Hello Peter!nYes, the initial temp of the parts if 20?C.nUnderstood, that was my doubt, it is clear now nThank you so much, I really appreciate your help!n
• amando.gallardo
Subscriber
HI Peter, I tried to set up the time step controls as you suggest, however I get an error: Invalid maximum time stepnHow can I to overcome this issue?nn