The row-start pointer array provided performance benefits on old
computers but now that computation is often cache-miss limited the
benefit of avoiding a integer multiply is more than offset by the
addition memory access into a separately allocated array.
With the new addressing scheme LUsolve is 15% faster.
in terms of the rotation tensor \c E and translation vector \c r .
See Chapter 2 and Appendix A in reference:
Featherstone, R. (2008).
Rigid body dynamics algorithms.
Springer.
This work is sponsored by Carnegie Wave Energy Ltd
Henry G. Weller
CFD Direct
Based on definitions in chapter 2 of the book:
Featherstone, R. (2008).
Rigid body dynamics algorithms.
Springer.
This work is sponsored by Carnegie Wave Energy Ltd
The particular rotation sequence is specified via the enumeration:
//- Euler-angle rotation sequence
enum rotationSequence
{
ZYX, ZYZ, ZXY, ZXZ, YXZ, YXY, YZX, YZY, XYZ, XYX, XZY, XZX
};
and provided as an argument to the constructor from Euler-angles
//- Construct a quaternion given the three Euler angles:
inline quaternion
(
const rotationSequence rs,
const vector& angles
);
and conversion to Euler-angles:
//- Return a vector of euler angles corresponding to the
// specified rotation sequence
inline vector eulerAngles(const rotationSequence rs) const;
Provides '(i, j)' element access and general forms of inner and outer
products, transpose etc. for square and rectangular VectorSpaces.
VectorSpaces default to be column-vectors as before whereas row-vectors
may be represented as 1xn MatrixSpaces. In the future it may be
preferable to create a specializations of VectorSpace for column- and
maybe row-vectors but it would add complexity to MatrixSpace to handle
all the type combinations.
Tensor is now a 3x3 specialization of MatrixSpace.
Sub-block const and non-const access is provided via the
'.block<SubTensor, RowStart, ColStart>()' member functions. Consistent
sub-block access is also provide for VectorSpace so that columns of
MatrixSpaces may be accessed and substituted.
These new classes will be used to create a more extensive set of
primitive vector and tensor types over the next few weeks.
Henry G. Weller
CFD Direct
Foam::direction is an unsigned type which makes it easier for the
compiler to pickup and report errors in the instantiation of
VectorSpaces and associated types.
1. "foamCompiler" was changed to a more permanent "WM_COMPILER_TYPE"
environment variable, so that it can be used by 3rd party
installation scripts, such as "makeGcc", "makeLLVM" and so on. More
on this will be provided in issue #1215.
2. The script functions such as "_foamSource()" and "_foamAddPath()"
were moved to a new file "etc/config.sh/functions". It has the
ability to set or unset, depending on whether "WM_BASH_FUNCTIONS" is
defined or not. This allows for these functions to be reused by
other scripts, such as "makeGcc".
3. The script "etc/config.sh/CGAL" relies on whether a local
environment variable "SOURCE_CGAL_VERSIONS_ONLY" is defined or not,
so that it will load only the version settings if it's defined. This
is to make it easier to call this script from "makeCGAL". Although
it still feels a bit of a clunky hack, but I didn't manage to deduce
any other way we could do this :( I didn't add indentation within
the if-block, to make it easier to read the changes. In addition,
the local variable "common_path" is used to shorten the length of
the lines and use slightly less repeated code.
4. Added another new script "etc/config.sh/compiler", which has only
the version numbers for the compilers taken out from the "settings"
file. It currently depends on "WM_COMPILER_TYPE" for setting the
variables, the same way it did with "foamCompiler". This script is
now always sourced from the "settings" file, for the following
reasons:
- "makeGCC" and "makeLLVM" can now take advantage of this script file.
- The example "compiler" script (detailed next) can rely on this
script file and then override parameters on-demand, as well as
allowing for system compilers to have dedicated settings, such as
setting "WM_CC". This is similar to how the example environment
script for "paraview" works.
5. To the script "etc/config.sh/example/compiler" were added a few more examples:
- It now starts with a block where it first loads the default "compiler" script.
- Has a "WM_COMPILER=Gcc48u" case example for when we try to use GCC
4.8 in Ubuntu 15.10. This is just to give the idea that in a
particular system, we might have several system-wide compiler
versions. For example, in Ubuntu 15.10, there is GCC 4.7, 4.8 and
5.2, which could be used for testing performances or compatibility
with some other 3rd party library.
- Has the "WM_COMPILER=Icc" case example, related to the original bug
report, where "WM_CC=icc" and "WM_CXX=icpc", so that the user then
simply copies this file to their own local preferences folder.
6. Small bug fix in "etc/config.sh/mpi", where unsetting "minBufferSize" was missing at the end of the script.
7. Small change in "etc/config.sh/paraview", where "CMAKE_ROOT" is set
along with "CMAKE_HOME". This is due to a rare issue that occurs on
people's systems where they have a custom system-wide CMake version
installed and which is used by having "CMAKE_ROOT" set on that
environment. This can mess up OpenFOAM's custom ParaView builds,
given that conflicting CMake versions can lead to not building
ParaView at all.
- For more details about "CMAKE_ROOT":
https://cmake.org/Wiki/CMake_Useful_Variables [^]
8. The scripts "_foamAddPath _foamAddLib _foamAddMan" were not being
unset at the end of "settings". They are now unset at the end of
"bashrc", through a call to the new double-use "functions" script.
Additionally all references to "foamCompiler" have been changed to
"WM_COMPILER_TYPE".
See also http://www.openfoam.org/mantisbt/view.php?id=1232
Wall-velocity condition to be used in conjunction with the single rotating
frame (SRF) model (see: FOAM::SRFModel)
The condition applies the appropriate rotation transformation in time and
space to determine the local SRF velocity of the wall.
\f[
U_p = - U_{p,srf}
\f]
where
\vartable
U_p = patch velocity [m/s]
U_{p,srf} = SRF velocity
\endvartable
The normal component of \f$ U_p \f$ is removed to ensure 0 wall-flux even
if the wall patch faces are irregular.
\heading Patch usage
Example of the boundary condition specification:
\verbatim
myPatch
{
type SRFWallVelocity;
value uniform (0 0 0); // Initial value
}
\endverbatim
