TurTLE stands for "Turbulence Tools: Lagrangian and Eulerian" and it is developed and maintained by the Wilczek group at the Max Planck Institute for Dynamics and Self-Organization and the University of Bayreuth in collaboration with the Application Support Group of the Max Planck Computing and Data Facility.
TurTLE is a framework for pseudo-spectral simulations of turbulence, with a highly optimized particle tracking method. It consists of a C++ core library, as well as a Python "wrapper" library. TurTLE is open sourced (GPLv3), you may access it here.
The documentation consists of two parts: