After gaining more experience with ASL I'm convinced that it is the best accelerated open source LBM-solver as of end of 2015. It has following important advantages:
- simple C++ API (and only C++ - no need to know OpenCL or Python even for adding new numerical methods (which will automatically become hardware accelerated)!)
- remarkable performance
- multiphysics: many other physical/chemical phenomena beside LBMbesides CFD (Lattice Boltzmann method is used in ASL)
- hardware accelerated, can be deployed on CPU/GPU/FPGA/DSP/APU-clusters
- mesh-free, immersed boundary technology allows to move from CAD directly to simulation (important for automated design optimization).
- dynamic compilation approach enables an additional layer of optimization at run-time (i.e. for a specific parameters set the application was provided with)
- open source: AGPL + optional commercial license for closed-source projects.