Main Page
Overview
openpipeflow.org is a free resource for researchers, engineers, educators and the interested public.
A simulation code and documentation on techniques and methods are provided. The majority of mathematical techniques described on these pages are applicable to a huge range of problems beyond pipe flow. The core code is designed to be flexible, and subroutines for some well-known methods are designed to be problem-independent.
Aims
- To make accessible a range of modelling techniques.
- To facilitate rapid entry into the world of numerical simulation and fluid dynamics.
- To provide flexible modules for more the use and development of advanced techniques in research.
Code features
- Primitive-variable pipe-flow code for incompressible flow.
- Simple scripts for visualisation with Matlab/Octave/Visit.
- May be run serial or parallel (with MPI). Essentially linear scaling with number of cores.
- [NEW July 2015] '2-dimensional' parallelisation, radial+axial split.
- Readable Fortran 90, uses modules and derived types, no esoteric extensions.
- Core program <3000 lines.
- Spatial discretisation: double-Fourier (theta,z) + finite difference (r).
- PPE formulation; influence matrix corrects boundary conditions to machine precision.
- Second-order predictor-corrector method, automatic timestep control.
Manual, Tutorial, FAQ
Links to the Manual, Tutorial and FAQ can be found on the left sidebar.
The Manual covers
- setup and typical usage of the code,
- definition of the model,
- mathematics behind the methods,
- conventions used in the code,
- description of utility codes.
The Tutorial guides a new user through
- setting up parameters for a job,
- monitoring a job's progress,
- simple plotting of time series from a run,
- visualisation of structures in a snapshot,
- manipulating data.
Download
See Download on left side-bar.
Database
The Database provides sample parameters and initial conditions from which to launch new simulations. In general, simulations start most reliably from an initial state computed for similar parameters. A range of starting points are provided.
Features to appear/wishlist
- Utilities for Krylov methods -- Newton-Krylov, Arnoldi.
- Module for the immersed boundary method (IBM).
- More FAQ + documentation.
Citation
- In talks:
openpipeflow.org
- In articles:
e.g. "using openpipeflow.org, based on code described in \cite{WK09}." @article{WK09, Author = {A. P. Willis and R. R. Kerswell}, Year = {2009}, Title = {Turbulent dynamics of pipe flow captured in a reduced model: puff relaminarisation and localised `edge' states}, Journal = {J.\ Fluid Mech.}, Volume = {619}, Pages = {213-233} }
Author
- Ashley P. Willis,
- School of Mathematics and Statistics (SoMaS),
- University of Sheffield, U.K.
- ashleypwillis/at/gmail.com
Thanks
- John Gibson (channelflow.org)
- Predrag Cvitanović (GaTech chaosbook.org)
- Rich Kerswell (Bristol)
- many other people!
- EPSRC GR/S76144/01, EP/K03636X/1
- The University of Sheffield.