The performance of Overtopping Wave Energy Converters is significantly dependent on the accurate estimation of wave overtopping discharge, which makes this parameter a key factor in the design of such structures. Analysis an‎d understan‎ding of the wave overtopping phenomenon requires precise examination of device geometry, sea state conditions, an‎d the hydraulic performance of wave run-up an‎d overtopping on the structureʹs slope. In the present research, 180 two-dimensional experiments were conducted to investigate wave overtopping an‎d run-up behavior under the influence of various OBREC device geometries an‎d different wave conditions. In this regard, a novel dimensionless parameter (H*√T*) was introduced to jointly eva‎luate the effects of wave height an‎d period, an‎d a new overtopping parameter (NOT) was proposed considering wave breaker type. Results indicated that the NOT parameter has appropriate predictive capability, with its coefficient of determination for plunging an‎d surging waves obtained as 88% an‎d 97%, respectively. Also, by analyzing wave behavior on the structureʹs slope, a critical value of the surf similarity parameter equal to 4.2 was identified between the plunging an‎d surging breaker ranges, which creates a distinct behavioral change in the wave run-up an‎d overtopping process. Analysis of the structureʹs geometry showed that increasing the freeboard of the reservoir slope an‎d a gentler reservoir slope lead to increased wave overtopping, while increasing the height of the reservoir slope an‎d a gentler breakwater slope result in reduced wave overtopping. Finally, through systematic investigation of all effective geometric an‎d sea state parameters, a predictive equation for both wave breaker types was presented with coefficients of determination of 82% an‎d 84%, for plunging an‎d surging waves, respectively. Compared to the best existing model, the proposed formula reduced the mean relative error by 98% an‎d achieved an average coefficient of determination of 83%. Given the complexity of wave-structure interaction, investigating wave run-up an‎d overtopping with a physics-based approach can provide deep insight into overtopping behavior in coastal structures, particularly in OBREC devices. In this research, a novel physics-based method for estimating wave run-up height an‎d overtopping discharge is presented, in which the maximum wave momentum flux at the structureʹs toe is correlated with the volume of the water wedge run up the structureʹs slope an‎d the water wedge that reaches the OBREC deviceʹs crest an‎d overtops it. Using this approach, an analytical-empirical model was developed capable of predicting wave run-up height with a coefficient of determination of 92% an‎d wave overtopping discharge of 87.34%. This model also considers flow thickness an‎d velocity at the reservoir crest. The main advantage of this method is its reliance on the physical principles of wave-structure interaction rather than sole dependence on empirical data. The proposed formulas, after validation with laboratory data, showed excellent agreement an‎d higher accuracy compared to conventional empirical methods. The findings of this research provide a reliable approach with systematic investigation of effective parameters across a wide range of data an‎d based on physical principles for the design of OBREC devices an‎d for improving the accuracy of predicting wave run-up an‎d overtopping.

محمدنويد مقيم

مهدي شفيعي فر

شهريار منصورزاده , بيژن برومند قهنويه , حسين افضلي مهر