Location 



Resistance wave gauges. Wave gauges were deployed at 12-ft (3.66-m) 

 intervals on the west wall of the channel. The most shoreward gauge was at 

 Station 6, x = 61 ft (18.6 m), and the most seaward at Station 21, jc = 241 ft 

 (73.5 m), in SUPERTANK coordinates (Chapter 1). The gauges were num- 

 bered 1 to 16 with Gauge 1 being the most shoreward and Gauge 16 the most 

 seaward. Gauge numbers correspond to the channels on which the data were 

 collected. Wave gauges were attached to the tank wall using existing 1-in. 

 (2.54-cm) wall inserts. Gauge mounts consisted of 1-in. (2.54-cm) aluminum 

 rods, threaded on one end to attach to the wall inserts. The other end of each 

 rod was machined to accept a Delrin plate, to which the wave gauge wires 

 were attached. The gauge mounts extended horizontally out from the wall 

 approximately 18 in. (0.46 m), y = 1.5 ft (0.46 m) and the gauges extended 

 vertically from z = -1.0 ft to -8.0 ft (-0.3 m to -2.4 m). The top mount 

 incorporated an adjustable eyebolt to set wire tension. 



Electromagnetic current meters. Fourteen current meters were deployed 

 on the east wall of the channel in vertical arrays of one to four gauges. The 

 arrangement of the current meters varied from week to week, with some 

 changes from run to run, to meet measurement objectives. Tables A2-A7 

 (contained in Volume II of this report) give the x, y, and z positions of the 14 

 wall-mounted current meters for the 6 weeks of SUPERTANK tests. The 

 current meters were numbered CM1 to CM18. Current meters CM13, 

 CM14, CM15, and CM16 were deployed in a vertical array (approximate 1-ft 

 (0.3-m) vertical spacing) off a mobile carriage. The position of the carriage 

 for each run is given in Table 1-2. The column labelled Elev is the vertical 

 reference for the current meters deployed off the carriage. The z position of 

 CM13, the bottom sensor in the array, is given by 4.9 ft (1.49 m) minus Elev 

 (Table 1-2); plus 0.98 ft (0.30 m) for z of CM14, plus an additional 0.90 ft 

 (0.27 m) for CM15, plus an additional 1.05 ft (0.32 m) for CM16. Columns 

 labelled Pos and RefSta (Table 1-2) are the horizontal references for the car- 

 riage. The x position of the current meters is located Pos inches seaward of 

 the given reference station. 



The current meter mounts consisted of aluminum plates and rods. The 

 plates were bolted into the wall inserts with 1-in. (2.54-cm) bolts. Spacers 

 welded to the back of the plates set the plates approximately 2 in. (5 cm) out 

 from the wall. A vertical array of rectangular slots was machined into the 

 plates at 6-in. (15.2-cm) spacings. Three-quarter-in. (1.9-cm) aluminum rods, 

 threaded and keyed on one end, slid into the slots in the plate and were 

 fastened with a nut on the backside of the plate (the space between the wall 

 and plate allowed access behind the plate). The elevation of the rods could be 

 easily adjusted between runs by removing the nut behind the plate and 

 refastening the rod into another slot. The opposite end of the rod was 

 machined flat on one side, and the mounting bar of the current meter was 

 attached to the flat portion of the rod with two small hose clamps. Current 

 meter cables were secured to the plate with cable ties attached through small 

 holes punched into the plate for that purpose. The meters extended 



Chapter 3 SUPERTANK Hydrodynamics 



57 



