文档介绍：Solver Control
Solver Control
Settings for the behavior of the CFX-5 solver
Maximum number of timesteps
Timestep selection
Transient timestep control for results output
Convergence criteria
Order of differencing scheme
Advanced Options
Mesh Adaption
Flow Solver Parameters Form
Convergence Control
Convergence criteria
Advection scheme
Options
Mesh Adaption
Also Timestep results selection for transient simulations
Transient Timesteps
Specify creation of transient results files
Set time to every for intervals or at for specific time values
Set Minimal Results File with specific variables to reduce file sizes (if not full results files get written at each timestep)
Only accessible if transient was selected in the Domain Options of the Domains form
Flow Solver Parameters Form
Convergence Control
Max. Number of Timesteps
Sets the maximum timesteps for the current run
Equation Class Scope
Timestep Selection
Auto Timestep
Physical Timestep
Auto Timestep User Max
Local Timestep Factor
Solver Parameters
Auto timestep.
Default setting for timestep control.
Use internally calculated fixed physical timestep size based on boundary conditions, initial guess and geometry of the domain.
Auto timestep: user maximum.
Use an internally calculated timestep, but the value is capped by a user specified maximum.
If the internally calculated timestep is less than the specified maximum, the solver uses this value for the first five timesteps. After five timesteps, the timestep is doubled for each essive timestep and checked against the specified maximum value. When this value is reached, it is used for the remaining timesteps.
If the internally calculated value is greater than or equal to the specified maximum, the maximum value is used for all timesteps.
Solver Parameters
Physical timestep
Permits true transient simulation
Value near an L/V scale usually gives good convergence rate
Not obvious sometimes
Solver Parameters
Local timestep factor, E.
Different time scales are used