Comparison of hydrodynamic performance of two types of wave energy converter-floating breakwater
-
摘要: 波能装置−浮式防波堤是将浮式防波堤与波能转换装置集成,兼具防波消浪和捕获波浪能的集成装置,能够有效降低单一功能波能转换装置的成本。研究者们提出了许多波能装置−浮式防波堤的结构型式,其中非对称式浮体结构相比于对称式浮体结构,在单向入射波的水动力性能方面拥有一定的优势。本文针对导桩锚泊的非对称式方箱−三角形挡浪板和方箱−垂直挡浪板两种浮体结构型式,通过数值模拟的方式,对比分析其水动力特性和波能俘获特性。数值模型基于黏性流体理论,以Navier-Stokes方程为控制方程,并采用VOF方法和浸没边界法求解自由面边界和流固耦合作用,探究不同入射波周期、水深和浮体排水条件下集成装置水动力性能(消波特性、能量耗散特性和波能俘获特性)变化趋势。结果表明,在近岸波浪条件下(5~8 s),垂直挡板型式集成装置适用于较小周期波浪(5~6 s),而三角挡板型式集成装置适用于较大周期波浪(6~7.5 s)。随着水深增大,波能俘获比总体上呈现缓慢增长的趋势。在主浮体吃水相同的情况下(排水量不同),两种结构的透射系数基本一致;而在排水量相同(主浮体吃水不同)的情况下,垂直挡板结构型式的防波效果更好,三角挡板结构型式波能俘获性能要优于垂直挡板结构型式。
-
关键词:
- 波能装置−浮式防波堤 /
- 结构型式 /
- 水动力性能 /
- 波能俘获 /
- 消波性能
Abstract: The wave energy converter-type floating breakwater is an integrated device of floating breakwater and wave energy converter, with both functions of wave protection and wave energy capture. The integration can effectively reduce the cost of wave energy converter with one single function. Researchers have proposed a variety of structural types of this integrated device. Among them, the asymmetric type has some advantages in hydrodynamic performance compared with the symmetric type under one single direction wave. In this study, two structural types of a square box-triangle baffle and a square box-vertical baffle are chosen to investigate the hydrodynamic characteristics and wave energy capture characteristics by numerical models. Based on the viscous fluid theory, the numerical model takes the Navier-Stokes equation as the control equation, and uses VOF method and immersion boundary method to solve the free surface boundary and fluid-structure interaction. The variation trend of hydrodynamic performances (transmission coefficient, energy dissipation and energy capture ratio) of the integrated device under different conditions of incident wave period, water depth and displacement volume are explored. The results show that, for the near shore waves, the vertical baffle type integrated device is suitable for the smaller period waves of 5−6 s, while the triangular baffle type integrated device is suitable for the bigger period waves of 6−8 s. As the water depth increases, the wave energy capture ratio generally shows a slow growth trend. In the case of the same draft of the main floating body (different displacement volume), the transmission coefficients of the two structures are basically the same. In the case of the same displacement volume (different draft of the main floating body), the vertical baffle structure has better wave-proof effect, and the wave energy capture performance of the triangular baffle structure is better than that of the vertical baffle structure. -
表 1 水深波浪周期和PTO阻尼系数工况参数表
Tab. 1 Table of condition parameter for water depth,wave period and PTO damping coefficient
结构型式 水深/m 波浪周期/s PTO阻尼系数/(kg·s−1) 三角挡板、垂直挡板 1.5 1.20 60,100,150,200,250 1.5 1.40 60,100,150,200,250 1.5 1.58 60,100,150,200,250 1.5 1.79 60,100,150,200,250 三角挡板 1.50,1.75,2.00,2.25,2.50 1.40 150 垂直挡板 1.50,1.75,2.00,2.25,2.50 1.40 200 表 2 主浮体吃水和排水量工况参数表
Tab. 2 Table of condition parameters for box draft and displacement volume
结构型式 主浮体吃水/m 排水量/m3 垂直挡板 0.15 0.0565 三角挡板 0.15 0.0978 垂直挡板 0.36 0.0978 表 3 网格参数设置
Tab. 3 Mesh parameter setting
算例 网格数 Δx/cm Δy/cm Test 1 458×170 2 1 Test 2 458×246 2 0.5 Test 3 554×246 0.8 0.5 Test 4 554×514 0.8 0.2 Test 5 718×514 0.4 0.2 Test 6 718×1 033 0.4 0.1 Test 7 958×1 033 0.2 0.1 表 4 两种结构型式在不同波浪周期下的最优PTO阻尼系数(BOPTO)
Tab. 4 Optimal PTO damping coefficient BOPTO of two structures in different wave periods
结构型式 入射波周期/s BOPTO/(kg·s−1) 三角挡板 1.20 150 1.40 100 1.58 150 1.79 200~250 垂直挡板 1.20 150 1.40 150 1.58 200 1.79 250 -
[1] 刘延俊, 武爽, 王登帅, 等. 海洋波浪能发电装置研究进展[J]. 山东大学学报(工学版), 2021, 51(5): 63−75.Liu Yanjun, Wu Shuang, Wang Dengshuai, et al. Research progress of ocean wave energy converters[J]. Journal of Shandong University (Engineering Science), 2021, 51(5): 63−75. [2] 谢典, 顾煜炯, 余志文, 等. 波浪能发电装置的性能分析及综合评价[J]. 水力发电学报, 2017, 36(8): 113−120.Xie Dian, Gu Yujiong, Yu Zhiwen, et al. Performance analysis and comprehensive evaluation of wave energy power generation devices[J]. Journal of Hydroelectric Engineering, 2017, 36(8): 113−120. [3] 孙科, 解光慈, 周斌珍. 波能装置浮子选型及水动力性能分析[J]. 哈尔滨工程大学学报, 2021, 42(1): 8−14. doi: 10.11990/jheu.201908011Sun Ke, Xie Guangci, Zhou Binzhen. Type selection and hydrodynamic performance analysis of wave energy converters[J]. Journal of Harbin Engineering University, 2021, 42(1): 8−14. doi: 10.11990/jheu.201908011 [4] Ning Dezhi, Zhao Xuanlie, Göteman M, et al. Hydrodynamic performance of a pile-restrained WEC-type floating breakwater: an experimental study[J]. Renewable Energy, 2016, 95: 531−541. doi: 10.1016/j.renene.2016.04.057 [5] Zhao Xuanlie, Ning Dezhi. Experimental investigation of breakwater-type WEC composed of both stationary and floating pontoons[J]. Energy, 2018, 155: 226−233. doi: 10.1016/j.energy.2018.04.189 [6] 毛艳军, 马哲, 程勇, 等. 动力输出系统(PTO)对集成波能转换装置式防波堤消波性能及波能捕获率影响研究[J]. 海洋工程, 2019, 37(4): 45−53.Mao Yanjun, Ma Zhe, Cheng Yong, et al. Effect of the PTO damping force on the wave damping performance and wave capture efficiency of a WEC-type breakwater[J]. Ocean Engineering, 2019, 37(4): 45−53. [7] 张恒铭. 波能装置与浮式防波堤集成系统的水动力特性研究[D]. 哈尔滨: 哈尔滨工程大学, 2019.Zhang Hengming. Study on hydrodynamic characteristics of integrated system of wave energy converter and floating breakwater[D]. Harbin: Harbin Engineering University, 2019. [8] 王世林, 于定勇, 谢雨嘉, 等. 方箱−垂直板浮式防波堤水动力特性研究[C]//海洋工程学会. 第十九届中国海洋(岸)工程学术讨论会论文集(上). 北京: 海洋出版社, 2019: 421-428.Wang Shilin, Yu Dingyong, Xie Yujia, et al. Study on hydrodynamic characteristics of square box-vertical plate floating breakwater[C]//Chinese Society for Oceanography. Proceedings of the Nineteenth Chinese Symposium on Ocean (Coastal) Engineering (I). Beijing: China Ocean Press, 2019: 421−428. [9] Ji Qiaoling, Xu Chenghao, Jiao Chunshuo. Numerical investigation on the hydrodynamic performance of a vertical pile-restrained reversed L type floating breakwater integrated with WEC[J]. Ocean Engineering, 2021, 238: 109635. doi: 10.1016/j.oceaneng.2021.109635 [10] 刘崇期. 兼具波浪能提取功能的浮式防波堤性能研究[D]. 大连: 大连理工大学, 2015.Liu Chongqi. Performance of floating breakwater double used as wave energy convertor[D]. Dalian: Dalian University of Technology, 2015. [11] 张亮, 国威, 王树齐. 一种点吸式波浪能装置水动力性能优化[J]. 哈尔滨工业大学学报, 2015, 47(7): 117−121.Zhang Liang, Guo Wei, Wang Shuqi. Hydrodynamic performance optimization of a point absorber[J]. Journal of Harbin Institute of Technology, 2015, 47(7): 117−121. [12] 陈子和, 嵇春艳, 郭建廷, 等. 振荡浮子式波能发电浮堤一体化装置性能研究[J]. 船舶工程, 2021, 43(10): 22−30.Chen Zihe, Ji Chunyan, Guo Jianting, et al. Performance investigation of an integrated device of oscillating buoy wave energy converter and Floating Breakwater[J]. Ship Engineering, 2021, 43(10): 22−30. [13] Zhu Xinying. Application of the CIP method to strongly nonlinear wave-body interaction problems[D]. Trondheim: Norwegian University of Science and Technology, 2006. [14] 赵西增, 刘必劲, 梁书秀, 等. 紧致插值曲线CIP方法及其应用[J]. 船舶力学, 2016, 20(4): 393−402.Zhao Xizeng, Liu Bijin, Liang Shuxiu, et al. Constrained Interpolation Profile (CIP) method and its application[J]. Journal of Ship Mechanics, 2016, 20(4): 393−402. [15] Xu Sheng, Wang Z J. An immersed interface method for simulating the interaction of a fluid with moving boundaries[J]. Journal of Computational Physics, 2006, 216(2): 454−493. doi: 10.1016/j.jcp.2005.12.016 [16] Xiao F, Honma Y, Kono T. A simple algebraic interface capturing scheme using hyperbolic tangent function[J]. International Journal for Numerical Methods in Fluids, 2005, 48(9): 1023−1040. doi: 10.1002/fld.975 [17] Xu Jing, Wang Dongshi, Huang Hui, et al. A vortex-induced vibration model for the fatigue analysis of a marine drilling riser[J]. Ships and Offshore Structures, 2017, 12(S1): S280−S287. [18] 刘冲. 垂直导桩锚固方箱−水平板式浮防波堤试验研究[D]. 大连: 大连理工大学, 2008.Liu Chong. Experimental study on pile-restrained pontoon-plates floating breakwater[D]. Dalian: Dalian University of Technology, 2008. [19] Koutandos E, Prinos P, Gironella X. Floating breakwaters under regular and irregular wave forcing: reflection and transmission characteristics[J]. Journal of Hydraulic Research, 2005, 43(2): 174−188. doi: 10.1080/00221686.2005.9641234 [20] He Fang, Huang Zhenhua, Law A W K. An experimental study of a floating breakwater with asymmetric pneumatic chambers for wave energy extraction[J]. Applied Energy, 2013, 106: 222−231. doi: 10.1016/j.apenergy.2013.01.013