PySPH: a Python-based SPH framework¶

Features¶

• User scripts and equations are written in pure Python.
• Flexibility to define arbitrary SPH equations operating on particles.
• Ability to define your own multi-step integrators in pure Python.
• High-performance: our performance is comparable to hand-written solvers implemented in FORTRAN.
• Seamless multi-core support with OpenMP.
• Seamless parallel integration using Zoltan.
• BSD license.

SPH formulations¶

Currently, PySPH has numerous examples to solve the viscous, incompressible Navier-Stokes equations using the weakly compressible (WCSPH) approach. The following formulations are currently implemented:

• Weakly Compressible SPH (WCSPH) for free-surface flows (Gesteira et al. 2010, Journal of Hydraulic Research, 48, pp. 6–27)

3D dam-break past an obstacle SPHERIC benchmark Test 2

• Transport Velocity Formulation for incompressilbe fluids (Adami et al. 2013, JCP, 241, pp. 292–307).

Streamlines for a driven cavity

• SPH for elastic dynamics (Gray et al. 2001, CMAME, Vol. 190, pp 6641–6662)

Collision of two elastic rings.

• Compressible SPH (Puri et al. 2014, JCP, Vol. 256, pp 308–333)

Credits¶

PySPH is primarily developed at the Department of Aerospace Engineering, IIT Bombay. We are grateful to IIT Bombay for the support. Our primary goal is to build a powerful SPH-based tool for both application and research. We hope that this makes it easy to perform reproducible computational research.

Lead developers:

• Prabhu Ramachandran
• Kunal Puri

Earlier developers:

• Pankaj Pandey (stress solver and improved load balancing, 2011)
• Chandrashekhar Kaushik (original parallel and serial implementation in 2009)

The following have contributed bug-fixes, features, documentation etc.

• Arkopal Dutt, Arpit Agarwal, Sarang Minhas, S Saravanan, Vishnu Sivadasan

Citing PySPH¶

We are in the process of writing up an article on the new PySPH framework as it stands today. In the meanwhile, if you use PySPH and wish to cite it you may use this:

• Prabhu Ramachandran and Kunal Puri, PySPH: A framework for parallel particle simulations, In proceedings of the 3rd International Conference on Particle-Based Methods (Particles 2013), Stuttgart, Germany, 18th September 2013.

History¶

• 2009: PySPH started with a simple Cython based 1D implementation written by Prabhu.
• 2009-2010: Chandrashekhar Kaushik worked on a full 3D SPH implementation with a more general purpose design. The implementation was in a mix of Cython and Python.
• 2010-2012: The previous implementation was a little too complex and was largely overhauled by Kunal and Pankaj. This became the PySPH 0.9beta release. The difficulty with this version was that it was almost entirely written in Cython, making it hard to extend or add new formulations without writing more Cython code. Doing this was difficult and not too pleasant. In addition it was not as fast as we would have liked it. It ended up feeling like we might as well have implemented it all in C++ and exposed a Python interface to that.
• 2011-2012: Kunal also implemented SPH2D and another internal version called ZSPH in Cython which included Zoltan based parallelization using PyZoltan. This was specific to his PhD research and again required writing Cython making it difficult for the average user to extend.
• 2013-present In early 2013, Prabhu reimplemented the core of PySPH to be almost entirely auto-generated from pure Python. The resulting code was faster than previous implementations and very easy to extend entirely from pure Python. Kunal and Prabhu integrated PyZoltan into PySPH and the current version of PySPH was born. Subsequently, OpenMP support was also added in 2015.

Support¶

If you have any questions or are running into any difficulties with PySPH, please email or post your questions on the pysph-users mailing list here: https://groups.google.com/d/forum/pysph-users

Please also take a look at the PySPH issue tracker.

Changelog¶