KTH_Examples

This repository contains set of examples demonstrating the use of Nek5000 framework and toolboxes developed at KTH. The more in-depth description of the framework can be found at its doxygen documentation page, which contains variety of important information starting at downloading options and ending with detailed code description. List of all available tools can be found here.

Usage

All examples contain necessary files for code compilation and running the case except those, that can be easily recreated using genbox or genmap. Moreover, to reduce a number of binary files in the repository, we do not include multiple copies of the same file, so e.g. ext_cyl.re2 exists only under ext_cyl_DNS and it has to be copied to ext_cyl_LIN or ext_cyl_SFD.

Each example consists of:

• required tools source and include files
• setup source file ###.usr
• required SIZE file containing definitions of static arrays dimensions
• compilation script compile_script
• makefile_usr.inc describing compilation rules for tools files
• runtime parameters file ###.par
• mesh description; it can be ###.box or ###.re2
• README.md listing all the tools

To compile the code:

• make sure compile_script has set execute bit (chmode u+x compile_script)
• edit compile_script to set proper compilers
• if you have not cloned this repo as a submodule of KTH_Framework, make sure that in the compile_script the TOOLBOX_SRC variable points to the root of KTH_Toolbox, and NEK_SOURCE_ROOT points to the root of Nek5000.
• clean directory ./compile_script --clean (with the first compilation on a given machine clean the libraries as well)
• build the code ./compile_script --all

To run the code:

• regenerate the mesh using genbox if ###.re2 is not present
• generate map file using genmap
• execute the code using scripts from Nek5000/bin/ directory

Example list

• ext_cyl_DNS - nonlinear simulation of the flow past circular cylinder
• ext_cyl_LIN - linear simulation of the flow past circular cylinder
• ext_cyl_SFD - nonlinear simulation of the flow past circular cylinder with Selective Frequency Damping to calculate base flow
• ext_cyl_ARN - linear stability tool for spectra calculation with Arnoldi algorithm
• ext_cyl_PWI - linear stability tool, power iteration
• phill_STAT - nonlinear simulation of flow over periodic hill to calculate turbulence statistics (can be run in 2D or 3D mode)
• phill_PSTAT2D - two-dimensional postprocessing of files produced by phill_STAT
• phill_PSTAT3D - three-dimensional postprocessing of files produced by phill_STAT
• pipe_STAT - like phill_STAT but with preriodic pipe and mesh generated with gmsh
• pipe_PSTAT2D - like phill_PSTAT2D but with preriodic pipe and mesh generated with gmsh
• phill_TRIP - nonlinear simulation of flow over periodic hill with tripping line
• phill_TSRS - nonlinear simulation of flow over periodic hill to collect time series for point set.
• pipe_gSyEM - generalsed synthetic eddy method for pipe inflow