352
CHAPTER 7. LABORATORY WAVE GENERATION
Figure 7.3: Dimensionless Mean Wave Power for Two-Dimensional Flumes
With Water on One Side of the Wave Board.
Experimental Validation
Ursell, Dean, and Yu (1960) provided experimental verification of the firstorder wavemaker theory for the case of a piston-type wave board. They
conducted experiments in a rectangular wave channel that was 90 cm deep,
76 cm wide, and about 30 m long. A 1:15 sloping beach was used to
absorb the wave energy. For small values of wave steepness in the range
0.002 < H/L < 0.03, their measurements of H/So were on the average 3.4%
below the first-order theory prediction for the range 0 < kh < 5. They
attributed the difference to leakage past the sides and bottom of the wave
board and to finite amplitude effects. The variation between the average
deviation and individual observations gave an estimated experimental error
of about 2%.
Finite amplitude effects were observed when Ursell, et al. (1960) compared theory to measurements of steeper waves in the range 0.045 < H/L <
0.048. Observed values of H/So averaged about 10% less than theory with
a deviation again on the order of 3%. This demonstrated that steep fl
CHAPTER 7. LABORATORY WAVE GENERATION
Figure 7.3: Dimensionless Mean Wave Power for Two-Dimensional Flumes
With Water on One Side of the Wave Board.
Experimental Validation
Ursell, Dean, and Yu (1960) provided experimental verification of the firstorder wavemaker theory for the case of a piston-type wave board. They
conducted experiments in a rectangular wave channel that was 90 cm deep,
76 cm wide, and about 30 m long. A 1:15 sloping beach was used to
absorb the wave energy. For small values of wave steepness in the range
0.002 < H/L < 0.03, their measurements of H/So were on the average 3.4%
below the first-order theory prediction for the range 0 < kh < 5. They
attributed the difference to leakage past the sides and bottom of the wave
board and to finite amplitude effects. The variation between the average
deviation and individual observations gave an estimated experimental error
of about 2%.
Finite amplitude effects were observed when Ursell, et al. (1960) compared theory to measurements of steeper waves in the range 0.045 < H/L <
0.048. Observed values of H/So averaged about 10% less than theory with
a deviation again on the order of 3%. This demonstrated that steep fl