Taylor Green Vortex

The Taylor-Green Vortex is a 3D turbulent flow benchmark case. It is particularly useful for code validation because the flow evolves in a deterministic manner from a simple initial condition. To set up the case, the following parameters are selected in the input file:

* ic_form=7 (selects the sinusoidal initial conditions)
* dt=0.0005
* n_steps=20/dt (the problem should be run for 20 seconds)
* dx_cyclic=2*pi
* dy_cyclic=2*pi
* dz_cyclic=2*pi (triply periodic boundaries)
* n_diagnostic_fields="2 vorticity q_criterion" (to see the turbulent flow structures)
* monitor_integrals_freq=100 (write integrated quantities every 100 timesteps)
* n_integral_quantities="2 kineticenergy vorticity" (write integrated kinetic energy and vorticity to history file)
* Mach_free_stream=0.08
* Re_free_stream=1600
* L_free_stream=1
* T_free_stream=300
* Mach_wall=0
* T_wall=300
* Mach_c_ic=0.08
* Re_c_ic=1600
* T_c_ic=300
* rho_c_ic=1

Set all the nx_, my_, mz_ and u_, v_, w_ parameters to 0.

To run the case you will need (preferably) at least 8 processors.

The results can be post-processed using the script plotstats.py. This will plot the integrated kinetic energy as tke.pdf. It will also plot the dissipation rate computed 2 ways: as the negative time derivative of integrated kinetic energy, and as a function of integrated vorticity. The dissipation rates are compared to DNS and DG results by Beck and Gassner (2012) and Chapelier et al (2012).