Generation of Linear Waves with Bottom Wave Makers Using Analytical Solutions and Extended Mild-Slope Equations

In this study, rectangular and triangular bottom waver makers were developed to generate linear regular waves in a flume using both analytical solutions and extended mild-slope equations. The bottom wave makers were found to more efficiently generate wave heights with operable strokes in shallow water than conventional piston and flap wave makers. For the bottom wave makers, the ratios of generated wave amplitude to bottom movement amplitude varied depending on the ratio of wave maker length to wavelength and also relative water depth. The triangular bottom wave makers can generate more correct forms of linear sinusoidal waves than the rectangular bottom wave maker. Linear bichromatic and irregular waves were successfully generated with the bottom wave makers using the extended mild-slope equations. Numerical simulations of the extended mild-slope equations showed that waves reflected from structures pass over the bottom wave makers with negligibly small reflection. The bottom wave makers can be used to efficiently generate linear long waves in a flume without disturbances of reflected waves from structures.