PNNL-13501 - Pacific Northwest National Laboratory

Figure 3a. Transparent Oso rendering of a particle trap
flow field experiment with thermal coupling being developed
in the EMSL. Two thick hollow cylinders are aligned endto-end
along the long axis of an enclosing cylinder. A
laminar flow field is induced within the enclosing cylinder
such that there will be a constant inflow (or outflow) into the
gap space between the two opposing cylinders. The purpose
of the computational experiment is to determine how to
control the flow field within the gap as a function of gas
material, geometric gap separation distance, and the flow
parameters.
Figure 3b. Slice of a NWGrid quarter mesh through the
flow cell in Figure 3a. The left-most edge is the vertical
centerline, and the right-most edge is in the air field external
to the apparatus. The horizontal centerline passes through
the middle of the gap space between the two opposing
annuli. Note the variation of the mesh resolution as a
function of geometric complexity. Faithful modeling of the
curved surfaces leading into and out of the central core gap
region is extremely important to the accuracy of the
hydrodynamic flow model.
114 FY 2000 Laboratory Directed Research and Development Annual Report
Figure 4a. Oso rendering of a stable, 3D ion trap, which is
designed to investigate the behavior and properties of ions in
coupled electric and magnetic fields. The apparatus has
been designed such that there are two ceramic insulation
supports, into which fit two symmetrically opposing goldplated
end disks. There is a pinhole in each end cap,
through which an ion stream will run for alignment
purposes. The eight gold-plated aluminum ring electrodes
sit on the ceramic insulation supports such that each
electrode is isolated, including from the top and bottom end
caps.
Figure 4b. Slice of a NWGrid mesh through the gap
between the gold-plated aluminum ring electrodes of the ion
trap experiment in Figure 4a. Refinement of the mesh
through the gap has been designed to allow the physics
package to resolve the boundary conditions of the field with
the geometric constraints of the electrodes.
as-needed basis. We also obtained LANL’s fully
parallelized X3D (for the generation of unstructured
grids), OSO (their volume rendering code to which may be
input CAD output), FEHM (their subsurface modeling
code), and CHAD (their combustion code). We
developed test problems. We also purchased