On Fri, Nov 15, 2013 at 3:40 PM, Geoffrey Irving <[email protected]> wrote: > On Fri, Nov 15, 2013 at 3:37 PM, Matthew Knepley <[email protected]> wrote: >> On Fri, Nov 15, 2013 at 5:31 PM, Geoffrey Irving <[email protected]> wrote: >>> >>> On Fri, Nov 15, 2013 at 3:21 PM, Matthew Knepley <[email protected]> >>> wrote: >>> > On Fri, Nov 15, 2013 at 5:09 PM, Geoffrey Irving <[email protected]> wrote: >>> >> >>> >> Is the second equation the weak form of incompressibility? If so, why >>> >> isn't q u? It's used as q several places throughout the code, so it >>> >> seems more likely to be my misunderstanding than a typo. >>> >> >>> >> < \nabla v, \nabla u + {\nabla u}^T > - < \nabla\cdot v, p > + < v, f >>> >> > = 0 >>> >> < q, \nabla\cdot v > >>> >> = 0 >>> > >>> > u, v \in V and p, q \in P, and hopefully \div V = P for stability. >>> >>> Are you using the same variables as >>> >>> >>> http://fenicsproject.org/documentation/dolfin/dev/python/demo/pde/stokes-iterative/python/documentation.html >>> >>> If so, maybe that line should be >>> >>> < q, \nabla\cdot u > >>> >>> I.e., "u" instead of "v"? >> >> >> Damn, you are right. > > Great, that makes it easier to understand. I'm trying to reverse > engineer the general definitions of all the fields in PetscFEM. It's > okay that they're not written down yet; it's probably better for me to > do this myself anyways to get a better feel for everything.
On irving/doc-cleanup as 30f909e1127f96586767d1a276195e9ca312e66c. Geoffrey
