About CFX convergence, the main indexes are flow, momentum residual, iteration steps and the balance of import and export flow. The convergence of different models is different. Some problems require high flow, and the error of import and export flow is less than 0. 1%, and some are 0.2%. Generally, the residual of flow momentum is set to 1.0E-06 when Pre is set, but it is generally not achieved. There are two ways to stop programming: 1. Stop manually and click Stop (note: this method can use the current calculation result as the initial field of the next calculation). 2. Stop automatically. There are two reasons for automatic stop: one is that the number of iteration steps reaches the set value, and the other is that "all residual values" reach the set value, such as 1.0E-06. When my import and export flow error is less than 0. 1% and the residual curve tends to be flat, my calculation is stopped manually. (Note: The way to check the flow balance in and out is to right-click next to Turbulence (KE) in the work area, create a new monitor, then click OK, find the item "Unbalance", open the model tree, find "P- mass balance (%)" and check it, and then click OK. )