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sherlock April 14, 2018 18:59

Transient Simulation Problem
 
Hello everybody,

I have a transient simulation. This simulation contains HVAC analysis of a tram. HVAC inlet is air conditioner. Inlet velocity is about 7 m/s and inlet temperature is 30 C. Initial temperature of tram is 10 C. Minimum mesh size is 2.5 e-3 m.

I tried different dt values. Finally, i worked with dt=0.5 s. It converges about 100 iteration with residual 5e-4. After a few dt, it starts to converge in 1-5 iterations. But results with short iteration period is not logical at the end of 5 minutes.

What is the problem in here?

Are residual values big?
Is dt big?

*I am using volume monitor to follow temperature.


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