how to solve max_error

[wanghai1988]

Hello,

I'm encountering a MassBalanceError while using ITZI and I'm seeking guidance on parameter adjustment. According to the documentation (since version 25.7), when volume error exceeds max_error, there are two main approaches to control it:

Reducing the time-step by adjusting the CFL parameter

Setting a maximum value for the time-step using dtmax

My questions are:

1、For the CFL parameter: should I decrease or increase its value to resolve mass balance issues?

2、For dtmax: what's the recommended adjustment strategy for this parameter?

Are there any general guidelines or best practices for tuning these parameters to achieve better mass conservation?

I'd appreciate any insights or recommendations on how to properly adjust these parameters to eliminate the MassBalanceError.

Thank you for your help!

[lrntct]

Hi. Lowering the values of both parameters will reduce the time-step duration, and therefore lower the mass balance error. Lower time-step duration also means slower simulation. So it's a balancing act between having good mass conservation and adequate speed.