1 Overview 2 Details of the Model Construction - Canada France ...

4 Dye Probe Locations
Dye probe ports were installed on the telescope floor, inside the, in the Cassegrain baffle and at several
locations on the terrain. The probe ports consisted of 9/32” (7.1 mm) brass tubing fitted with Delrin
caps and packed with dense open-cell foam (art foam) to provide friction. The Delrin caps were drilled
to allow insertion of 17 gauge 304 stainless hypodermic tubing. The inner and outer diameter of the
tubing was 0.047” (1.19 mm) and 0.058” (1.47 mm), respectively. With this arrangement the stainless
tubing could be easily moved up and down through the port to adjust the height of the probe in relation
to the model. The probes external to the model (labeled “B” below) had a 90 o , 0.25” radius bend, ~0.5”
(12.7 mm) long formed to allow the dye to be injected into the flow in a more laminar nature. The dye
ports were labeled as follows;
Inside the dome:
A1: Probe installed so that the dye exits at the level of the Cassegrain mirror fold above the
primary mirror.
A2: Probe on the north side of the telescope pier at a 2” (50.8 mm) radial distance from the
dome center.
A3: Probe on the east side of the dome (same radial distance from the dome center as A2).
A4: Probe on the south side of the telescope pier (same radial distance as A2).
A5: Probe on the west side of the telescope pier (same radial distance as A2).
Outside the dome:
B1, B2, B3, B4, B5: Probes from North to South respectively on the upwind (east) side of the
dome, 7.5 cm distant from the building measured along an east/west line.
B6: Probe located directly upwind (east) on the down-slope of the terrain, 20.7 cm from the
dome building as projected on the horizontal plane.
B7: Probe located directly downwind (west) of the dome, approximately 4 cm from the
building.
Probes B1 to B7 could be inserted to be at any level, from a maximum extension in level with the
mezzanine to being totally retracted in their grooves; this permitted us to visualize the flow at various
heights above the terrain.
5 The UWAL 30” Water Tunnel Facility
The UWAL 30” water tunnel is located in the Aerodynamics Laboratory on the UW main campus in
Seattle Washington. Jack Ross (electrical engineer) is the business manager for the Kirsten Wind
Tunnel as well as for the water tunnel facility. The water tunnel itself is maintained by Robert Gordon
(research engineer) and was originally built by professor Robert (Bob) Breidenthal and his students.
Following is the contact information for these individuals:
Jack Ross: 206 543-0439, jwross@u.washington.edu
Robert Gordon: 206 685-3011 (office), 206 713-2971 (cell), deepsnow@aa.washington.edu
Robert Breidenthal: 206 685-1098, breident@aa.washington.edu
The CFHT staff involved in performing the tests in Seattle were Karun Thanjavur, Tom Benedict and
Marc Baril. Derrick Salmon observed and provided guidance via internet teleconference from Waimea.