Numerical Study on the Linear and Nonlinear Behavior of A Fluid-Filled Piezoelectric Membrane Under Gravity Waves

This study integrated piezoelectric layers in a flexible membrane to form a piezoelectric membrane.A fluid-filled piezoelectric membrane,which can be used as breakwater and wave energy converter simultaneously,was presented.The mathematical models to describe the interactions of the waves with the piezoelectric membrane were given.The dimensionless parameters to control the behavior of the piezoelectric membrane were obtained.The mixed EulerianLagrangian method was employed to simulate the mathematical models.The simulation code was verified.Based on the simulation results,the effects of dimensionless elastic modulus of the membrane E^(*),tension of the membrane T_(0)^(*)and the resistance of the load R^(*)on the behavior of the piezoelectric membrane were discussed.As E^(*)is small(E^(*)<0.04)and T_(0)^(*)is not too small(T_(0)^(*)>0.0001),the response of the piezoelectric membrane can be considered as linear.For linear response,the minimum transmission coefficient and maximum output electric power of the piezoelectric membrane can be achieved simultaneously by adjusting T_(0)^(*)and R^(*).For larger E^(*),nonlinear behavior of the piezoelectric membrane is observed.At some larger values of E^(*),working frequency of piezoelectric elements can reach eight times the wave frequency.In these cases,higher output electric power can be achieved for smaller strain of the membrane.