p.v. panel wind load effects m arch 2011 arman hemmati, brady zaiser, chaneel park, jeff symons,...
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P.V. PANEL WIND LOAD EFFECTS
MARCH 2011
Arman Hemmati , Brady Zaiser, Chaneel Park, Jeff Symons, Katie Olver
In-Class Presentation
TEAM 12
MARCH- 2011In-Class Presentation: DeLoPREC
2
Introduction – Problem
• Most efficient sun capture at 51°
• Higher angle means greater aerodynamic forces
• Ballast required to hold the panel down
• Too much weight for the roof?
• Want to better understand wind loads on PV panels:
▫ Wind Tunnel Testing▫ Computational (CFD) Analysis
MARCH- 2011In-Class Presentation: DeLoPREC
3
Objectives – Functional Requirements
1. Effect of Wind Direction▫ Front or back
2. Effect of Panel Tilt ▫ Preferred angle is 51°
3. Proximity of Panel to the Ground▫ Should reduce drag to a point
MARCH- 2011In-Class Presentation: DeLoPREC
4
Wind Tunnel – Test Apparatus
MARCH- 2011In-Class Presentation: DeLoPREC
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Wind Tunnel – Testing Parameters
•Wind direction▫How does the force on the panel change
depending on the wind direction? Front, back
▫2 levels
MARCH- 2011In-Class Presentation: DeLoPREC
6
Wind Tunnel – Testing Parameters•Panel angle
▫How does the force on the panel change as the angle increases?
▫In Calgary the ideal angle is 51°▫Testing at:
35°, 50°, 65° and 80°▫4 levels
MARCH- 2011In-Class Presentation: DeLoPREC
7
Wind Tunnel – Testing Parameters
•Panel height▫How does the force on the panel change as
the distance between the ground and the bottom of the panel increases?
▫Unable to use CFD for this▫ Testing at:
0, 1”, 2”, …, 6”▫7 levels
MARCH- 2011In-Class Presentation: DeLoPREC
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Wind Tunnel – Testing Procedure
•How many runs?▫2∙4∙7 = 56 runs per replication▫2 replications = 112 runs
•Randomize run order▫Lots of set-up between runs
•How long will it take?▫5 min/run + daily set-up ▫Estimate 15 hours 1 week
MARCH- 2011In-Class Presentation: DeLoPREC
9
Computational Fluid Dynamics
• 2D Simulations• Using Comsol Multiphysics and Ansys CFX
MARCH- 2011In-Class Presentation: DeLoPREC
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CFD - Verification
• Results recorded in ratios (CL, CD, CP)
• Vertical Flat Plate
• Reference: “On the Flow of Air Behind an Inclined Flat Plate of Infinite Span” -Fage and Johansen, 1927.
MARCH- 2011In-Class Presentation: DeLoPREC
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13 13.5 14 14.5 15 15.5
-1.6
-1.1
-0.6
-0.1
0.4
0.9
FrontBack
Distance Along Y-Axis (m)
Pre
ssure
(P
a)
MARCH- 2011In-Class Presentation: DeLoPREC
www.ucalgary.ca/deloprec
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