Ocean wave energy is a significant and promising source of renewable energy.However,the energy harvesting is challenging due to the multi-directional nature of waves.This paper proposes a magnetic-field-assisted tribo...Ocean wave energy is a significant and promising source of renewable energy.However,the energy harvesting is challenging due to the multi-directional nature of waves.This paper proposes a magnetic-field-assisted triboelectric nanogenerator(MFATENG)for harvesting multi-directional wave energy.By incorporating a magnetic field,the planar motion of the pendulum is converted into spatial motion,increasing the triggering of multilayered TENG(M-TENG)and enhancing the output energy of the MFA-TENG.Experimental results demonstrate that the output energy of the MFA-TENG is increased by 73%by utilizing the magnetic field.Moreover,a spring model based on the origami-structured M-TENG is established to analyze the effect of different equivalent stiffnesses on the performance of the M-TENG,aiming to obtain optimal output performance.The results showcase the impressive output performance of the M-TENG,generating outputs of 250 V,18μA,and 255 nC.Furthermore,the proposed MFA-TENG effectively harvests multi-directional wave energy under water-wave driven conditions.This study significantly enhances the ability of the MFA-TENG to harvest multi-directional wave energy and presents a promising approach for self-powered marine monitoring in the future.展开更多
A numerical model is proposed based on the time domain solution of the Boussinesq equations using the finite element method in this paper. The typical wave diffraction through a breakwater gap is simulated to validate...A numerical model is proposed based on the time domain solution of the Boussinesq equations using the finite element method in this paper. The typical wave diffraction through a breakwater gap is simulated to validate the numerical model. Good agreements are obtained between the numerical and experimental results. Further, the effects of the wave directionality on the wave diffraction through a breakwater gap and the wave transformation on a planar bathymetry are numerically investigated. The results show that the wave directional spreading has a significant effect on the wave diffraction and refraction. However, when the directional spreading parameter s is larger than around 40, the effects of the wave directional spreading on the wave transformation can be neglected in engineering applications.展开更多
Extensive 3-D model tests have been performed to study the effects of wave obliquity and multi-directionality on the wave loads acting on vertical breakwaters. The variation of horizontal and uplift forces acting on a...Extensive 3-D model tests have been performed to study the effects of wave obliquity and multi-directionality on the wave loads acting on vertical breakwaters. The variation of horizontal and uplift forces acting on an unit length of a breakwater with wave direction, the longitudinal distribution of wave forces, as well as the longitudinal load reduction are analyzed. Some empirical formulae of the longitudinal distribution coefficient and the longitudinal load reduction factor are presented for practical use.展开更多
基金supported by the National Key Research and Development Project from Minister of Science and Technology of China(Nos.2021YFA1201604 and 2021YFA1201601).
文摘Ocean wave energy is a significant and promising source of renewable energy.However,the energy harvesting is challenging due to the multi-directional nature of waves.This paper proposes a magnetic-field-assisted triboelectric nanogenerator(MFATENG)for harvesting multi-directional wave energy.By incorporating a magnetic field,the planar motion of the pendulum is converted into spatial motion,increasing the triggering of multilayered TENG(M-TENG)and enhancing the output energy of the MFA-TENG.Experimental results demonstrate that the output energy of the MFA-TENG is increased by 73%by utilizing the magnetic field.Moreover,a spring model based on the origami-structured M-TENG is established to analyze the effect of different equivalent stiffnesses on the performance of the M-TENG,aiming to obtain optimal output performance.The results showcase the impressive output performance of the M-TENG,generating outputs of 250 V,18μA,and 255 nC.Furthermore,the proposed MFA-TENG effectively harvests multi-directional wave energy under water-wave driven conditions.This study significantly enhances the ability of the MFA-TENG to harvest multi-directional wave energy and presents a promising approach for self-powered marine monitoring in the future.
基金Project supported by the National Natural Science Foun-dation of China(Grant Nos.51079023,51221961 and 51309050)the National Basic Research Development Program of China(973 Program,Grant Nos.2013CB036101,2011CB013703)
文摘A numerical model is proposed based on the time domain solution of the Boussinesq equations using the finite element method in this paper. The typical wave diffraction through a breakwater gap is simulated to validate the numerical model. Good agreements are obtained between the numerical and experimental results. Further, the effects of the wave directionality on the wave diffraction through a breakwater gap and the wave transformation on a planar bathymetry are numerically investigated. The results show that the wave directional spreading has a significant effect on the wave diffraction and refraction. However, when the directional spreading parameter s is larger than around 40, the effects of the wave directional spreading on the wave transformation can be neglected in engineering applications.
文摘Extensive 3-D model tests have been performed to study the effects of wave obliquity and multi-directionality on the wave loads acting on vertical breakwaters. The variation of horizontal and uplift forces acting on an unit length of a breakwater with wave direction, the longitudinal distribution of wave forces, as well as the longitudinal load reduction are analyzed. Some empirical formulae of the longitudinal distribution coefficient and the longitudinal load reduction factor are presented for practical use.
