T-SAIL WiKi

In the summer of 2019, two new honeycombs were installed on the shelf of the wind flume.

The honeycomb was ordered from PLASCORE with the following parameters:

• ALSLICE ALUMINUM HONEYCOMB
  
• PCGA-XR2-1.2-1/0-30-P-3003
  
• 70 X 1524 X 2000 [mm^3]
• Perforated core
• Expanded Sheets
• XR2 corrosion coating is a chrome-free clear protective film
  • cost was 837.34 USD for two sheets, including shipment, NOT including tax.

The honeycombs were glued on to aluminum frames (80 [mm] depth) and placed in two locations:

• Upper honeycomb:
  • roughly 31 [cm] height
  • roughly 100 [cm] from wind inlet
  • tilted forward roughly 8 [deg]
  • held into place by two bolts and two 90 degree angles that were drilled into the shelf

• Lower honeycomb:
  • roughly 58 [cm] height
  • roughly 175 [cm] from wind inlet
  • has two main vertical positions:
    • straight (i.e. STR)- positioned vertically relative to water surface
    • angled (i.e. ANG)- positioned forward to roughly 8 [deg]
  • held into place by two bolts and two 90 degree angles that were drilled into the shelf

On July 16-17 2019, measurements of instantaneous water surface fluctuations were performed, using three consecutive wave gauges (WG) with the following parameter changes:

• blower frequencies (20, 30 & 40 [Hz])
• fetches (450 & 1100 [cm]) from the upper honeycomb
• vertical position of the Lower honeycomb (STR & ANG)

Measurement constants:

• water depth of 72 [cm] (overflowing the shelf)
• sample frequency of 80 [Hz]
• measurement time of 6,000 [sec]
• surge distances between the WG were:
  • 2.05 [cm] between WG1 & WG2
  • 9.75 [cm] between WG2 & WG3

Window averaging (No Overlapping) was preformed on the measurements with the following parameters:

• window size- 409.6 [sec]
• number of windows- 14

Spectra of both amplitude and power density (PDS) were plotted and are presented here: