# Guide to Version v7

With v7.0 we have introduced a lot of updates and changes that affect how you interact with the code. This document gives an overview on the most important changes, so that you can quickly update your existing config files to be compatible with v7.0.

### Definition of the physical problem and solver

The option PHYSICAL_PROBLEM has been renamed to SOLVER. The rational behind this change is that we are going to have several different solvers in the future which essentially solve the same physical problems. You can find a list of current solvers in the new Solver Setup section.

### Definition of the incompressible solver

The option REGIME_TYPE has been removed. In line with the change above, the incompressible solver is now specified using the SOLVER option by setting it to INC_EULER, INC_NAVIER_STOKES or INC_RANS.

### Controlling the solver

We have made the control of the different solvers more consistent. In particular setting the number of iterations. The option EXT_ITER has been removed and is replaced depending on the definition of the problem. Options for defining a time-dependent problem also changed. More details can be found in the table below and in section Solver Setup.

Old option name New option name Note
EXT_ITER INNER_ITER/ITER or OUTER_ITER or TIME_ITER Depending on the problem
UNSTEADY_SIMULATION TIME_MARCHING Option values are the same as before
- TIME_DOMAIN Value YES enables the time-dependent mode (default is NO)
UNST_TIMESTEP TIME_STEP -
UNST_TIME MAX_TIME -
UNST_TIME_ITER INNER_ITER -

### Output options

A lot of effort has been put into making the output more customizable. Below you find a list of options that have changed.

Old option name New option name Note
SOLUTION_FLOW_FILENAME SOLUTION_FILENAME -
RESTART_FLOW_FILENAME RESTART_FILENAME -
SURFACE_FLOW_FILENAME SURFACE_FILENAME -
VOLUME_FLOW_FILENAME VOLUME_FILENAME -
OUTPUT_FORMAT TABULAR_FORMAT This option now defines only the format of tabular outputs like the history files (values are CSV, TECPLOT)
- OUTPUT_FILES Replaces the options WRT_VOL_SOL, WRT_SRF_SOL, WRT_CSV_SOL, WRT_BINARY_RESTART, by specifying a list of files to output (see Custom Output)
WRT_SOL_FREQ_DUALTIME, WRT_SOL_FREQ OUTPUT_WRT_FREQ -
WRT_CON_FREQ_DUALTIME, WRT_CON_FREQ SCREEN_WRT_FREQ_INNER, SCREEN_WRT_FREQ_OUTER, SCREEN_WRT_FREQ_TIME Same options exist for history output (by replacing SCREEN_* with HISTORY_*)
WRT_OUTPUT - Removed. Equivalent behavior can be achieved by setting OUTPUT_FILES to NONE
WRT_RESIDUALS, WRT_LIMITERS VOLUME_OUTPUT Add the corresponding fields to the new option
LOW_MEMORY_OUTPUT - Removed. Equivalent behavior can be achieved by setting VOLUME_OUTPUT to COORDINATES, SOLUTION

Important note: Visualization files are now also written when the code runs in parallel (if added to OUTPUT_FILES).

### ASCII Restart format

The ASCII restart format has been changed to a CSV format. As a consequence ASCII restart files generated with a version before 7.0 are not compatible any more. However, in your installation directory you will find a python script called convert_to_csv.py that will convert old restart files to the new format. On your commandline use

convert_to_csv.py -i your_restart.dat


to run the script. This will create a file called your_restart.csv wich can be used as input if you disable reading binary files with READ_BINARY_RESTART set to NO.

### Grid/mesh movement

Mesh movement has been split into grid movement (motion is applied on the whole mesh, GRID_MOVEMENT option) and surface movement (motion is defined for a particular marker, SURFACE_MOVEMENT option).

Option Option values Options to define the movement
GRID_MOVEMENT RIGID_MOTION, ROTATING_FRAME, STEADY_TRANSLATION MOTION_ORIGIN, TRANSLATION_RATE, ROTATION_RATE, PITCHING_OMEGA, PITCHING_AMPL, PITCHING_PHASE, PLUNGING_OMEGA, PLUNGING_AMPL
SURFACE_MOVEMENT DEFORMING, MOVING_WALL, EXTERNAL, EXTERNAL_ROTATION SURFACE_MOTION_ORIGIN, SURFACE_TRANSLATION_RATE, SURFACE_ROTATION_RATE, SURFACE_PITCHING_OMEGA, SURFACE_PITCHING_AMPL, SURFACE_PITCHING_PHASE, SURFACE_PLUNGING_OMEGA, SURFACE_PLUNGING_AMPL

### Setting convergence criteria

Below are the options that have changed or are removed:

Old option name New option name Note
RESIDUAL_MINVAL CONV_RESIDUAL_MINVAL -
CAUCHY_ELEMS CONV_CAUCHY_ELEMS -
CAUCHY_EPS CONV_CAUCHY_EPS -
CONV_CRITERIA CONV_FIELD Accepts all fields available as output for the current solver (see Solver Setup)
RESIDUAL_REDUCTION - Removed. Equivalent behavior can be achieved by choosing a relative residual field for CONV_FIELD and setting CONV_RESIDUAL_MINVAL appropriately.