Flow over a heliostat example

[brookeslawski]

This pull request adds an example of using PVade to simulate wind loading of a heliostat (used in concentrating solar power) rather than a PV panel. The example is documented in User Manual > Examples > Heliostat 3D.

To adapt PVade to modeling heliostats, I created a geometry module folder called heliostats3d, which is similar to panels3d, but has different specification of the fixation points on the back side of the heliostat. These fixation points better represent how a typical heliostat is mounted.

This functionality and associated documentation will aid general users in modeling loads on generalized solar collector designs.

[brookeslawski]

To allow for heliostats, which are larger than PV panels

[arswalid]

pytests are passing, and documentation builds. other changes add if condition for heliostat

[eyoung55]

looks good to me! the domain setup and definitions, e.g., this is how we define chord", are awesome!

[eyoung55]

let's wait to merge until we get the code from kestrel (no rush to reproduce it locally) that rotates the measured point wrt the inflow wind direction.

[brookeslawski]

let's wait to merge until we get the code from kestrel (no rush to reproduce it locally) that rotates the measured point wrt the inflow wind direction.

Pulled in the code from kestrel. So once the checks complete, we should be all good.