Synthetic Turbulence Generator Parameters

Since revision r2259, a synthetic turbulence generation method is available in PALM. The turbulence generator follows the method proposed by Xie and Castro (2008) with a modification by Kim et al. (2013). Please see the documentation for a detailed description of the synthetic turbulence generator.

All parts of the synthetic turbulence generator are modularized in module synthetic_turbulence_generator_mod. In this context, a new Fortran NAMELIST stg_par was added, containing all related steering parameters.

NAMELIST group name: stg_par

Parameter Name	FORTRAN Type	Default Value	Explanation
dt_stg_adjust	R	300	Time interval (in seconds) to adjust the turbulence statistics, i.e. the Reynolds-stress tensor, which define the amplitude and correlation of imposed correlation. Please note, this parameter becomes only effective if turbulence statistics are parametrized, i.e. if they are not read from the ASCII input file. Further, dt_stg_adjust is only relevant in case of a daily cycle, where the strength of turbulence and boundary-layer depth changes in time.
dt_stg_call	R	5	Time interval to call the synthetic turbulence generator. With this parameter it is possible to skip calling the turbulence generator, in order to save computational resources.
use_syn_turb_gen	L	.F.	Flag to switch on the synthetic turbulence generator. If use_syn_turb_gen = .T., it is required to also set initializing_actions to either 'set_constant_profiles' or 'read_restart_data'. Also, non-cyclic boundary conditions along x-direction (bc_lr='dirichlet/radiation') and cyclic boundary conditions along y-direction (bc_ns='cyclic') have to be used. Using turbulence recycling (turbulent_inflow=.T.) together with the synthetic turbulence generator is not allowed.