This repository is the reference implementation of the GKE described in
D. Gatti et al., "An efficient numerical method for the Generalized Kolmogorov Equation", Journal of Turbulence, 20 (8), 457–480, 2018
The code is:
- Simple: it consists of few lines of code
- Parallel: with shared and distributed memory parallelization
- Efficient: it leverages Fast Fourier Transform algorithms whenever possible
The code is written in the programming language CPL, whose compiler can be downloaded here.
The computation is divided in three steps, each of them provided as a separate program:
- step1/step1_singlepoints.cpl: the computation of the single-point budgets of the Reynolds stresses
- step2/step2_gke.cpl: the computation of the GKE terms that do not involve a wall-normal derivatives
- step3/step3_gke.cpl: the computation of the GKE terms involving wall-normal derivatives
In the directory tutorial you can find the bash script tutorial/run_tutorial.sh which will compile the code and run it on simple test data, which correspond to a Minimal Flow Unit (MFU) at a friction Reynolds number of . The tutorial requires a working CPL installation and MATLAB, in order to visualise the results.
The memory requirement of Step 2) can be further reduced by commenting the line
#define wholefiled
of step2/step2_gke.cpl (line 17). Doing so will deactivate loading the whole velocity field and only a pair (iy1,iy2) of wall-parallel planes of the velocity field will be loaded at a time. Beware that this increases the I/O and possibly slows down calculations.
The directory database constains the GKE analysis performed for turbulent channels at two different values of friction Reynolds number Retau=200 and Retau=1000. Refer to database/README.md for further information!
Dr. Davide Gatti
davide.gatti [at] kit.edu
msc.davide.gatti [at] gmail.com
Karlsruhe Institute of Technology
Institute of Fluid Dynamics
Kaiserstraße 10
76131 Karlsruhe
If you use this code and find it helpful, please cite:
D. Gatti et al., "An efficient numerical method for the Generalized Kolmogorov Equation", Journal of Turbulence, 20 (8), 457–480, 2018