Closure Schemes for Nonlinear Bi-stable Systems subjected to Correlated Noise - Applications to Energy Harvesting from Water Waves

Moment Equation Closure Minimization (MECM) method has been developed for the inexpensive approximation of the steady state statistical structure of bistable systems which have bimodal potential shapes and which are subjected to correlated excitation. Our approach relies on the derivation of moment equations that describe the dynamics governing the two-time statistics. These are then combined with a closure scheme which arises from a non-Gaussian pdf representation for the joint response-excitation statistics. We demonstrate its effectiveness through the application on a bistable nonlinear single-degree-of-freedom ocean wave energy harvester with linear damping and the results compare favorably with direct Monte Carlo Simulations.