[rmotwan]

Hi all,

I'm running an engine simulation using G-Equation model. I noticed that my simulations are forced into recoveries and dt_chem limits the timestep to dt_min.

How does changing the value of mult_dt_chem affect the timestep changes? According to the description of mult_dt_chem, the value limits the change in temperature? What's the motivation behind limiting this temperature change?

Thank you for the help!

[rvigneshwar]

Originally Posted by rmotwan

Hi all,

I'm running an engine simulation using G-Equation model. I noticed that my simulations are forced into recoveries and dt_chem limits the timestep to dt_min.

How does changing the value of mult_dt_chem affect the timestep changes? According to the description of mult_dt_chem, the value limits the change in temperature? What's the motivation behind limiting this temperature change?

Thank you for the help!

dt_chem.png
The relation between the mult_dt_chem and the time step is shown in the image attached. The multiplier restricts the temporal jump in Temperature relative to the local temperature value, this is for smoothing the temperature with time. Generally, you can increase this multiplier (>0.5 and <1) if the simulation is getting restricted by this limiter. This will in turn remove the dt_chem limiter, but increase the solver load for solving transport equations.