The dual flap paddle consists of a moving paddle with two horizontal hinges. The first one is located near the bottom and the other near the surface. Below the first hinge the wavemaker is stationary. The geometry is input into the applet by the elvations of the hinges above the wave tank bottom.

The wavemaker can move in several different modes. Three are allowed here: the first is the upper paddle (above the second hinge) alone is moving, the second is that the upper paddle and the second move together as a single flap wavemaker, and the third mode is that the upper paddle is kept vertical. You can chose any of these modes.

The height of the wave created by the paddle motion is related to the stroke of the paddles, which will be denoted by the total horizontal displacement of the paddle at the still water line for all modes. This applet solves for the stroke, given the desired wave height and period.

The mean power (given in watts) required to make the desired wave is determined using a fluid density of 1000 kg per cubic meter. For different fluid densities, divide the result by 1000 and multiply by your density. The instantaneous power required to make the waves will be more than twice the mean power.

Comments: Robert Dalrymple
Center for Applied Coastal Research
University of Delaware, Newark DE 19716
USA