Calculations
Using OWC to Estimate Wave Height
} Wave Pressure: P(z)=-ρgz + ρgKpη
} Assume Shallow Water => Kp = 1 } Assume: Max U occurs at τ/2 } Therefore: ΔP = ρgH, ΔV=H * A0, Δt=τ/2 } Q=H*A0/(τ/2) } Q= A1*U } H= A1*U*(τ/2)/A0 |
Results} Measured:
A0= 45.6 cm. sq. A1=1.27 cm. sq. τ = 2 sec. U= 20 cm/s H=2.54 cm } Calculated: H= A1*U*(τ/2)/A0 H=0.55 cm |
Discussion} Possible Sources of Error
-Shallow Water Assumption: formulas used would have changed -Strainer Blocking Flow: not a big of pressure difference created as what could have been -Oscillating Air Flow Interference -Wave Reflection Interference: Readings desturbed because of the waves refraction on the bathtub walls -Measurement Error: human error -Uneven wave generation |
ConclusionOscillating Water Column is an excellent method for converting wave energy to usable power. Unfortunatly it is not being used yet as a common source of energy.
Using OWC to indirectly measure wave height should only be considered if interfering variables can be kept to a minimum. |
University of Wisconsin Madison
CEE 514: Final Project
By: Nicole Johnson & Eric Olson
Copyright 2010
CEE 514: Final Project
By: Nicole Johnson & Eric Olson
Copyright 2010