双俘能原理波浪能转换装置的关键技术研究

A novel wave energy conversion device composed of a semi-submerged circular cylinder whose bottom and top are open and fitted with a gas turbine generator, respectively, and several floaters hinged around the cylinder is proposed, and an in-depth investigation into the performance of this device is conducted by using the combined method of theoretical analysis, numerical simulation and experimental study. A dynamic model for coupling fluid-structure-PTO-mooring system with multi-structures, multi-dimensional motion and multi-principles of energy harvesting is established. Based on this model an optimization theory for the wave energy conversion system with multi-structures is developed. The mechanism of interaction between two kinds of energy harvesting principles’ system under wave action is explored. The operation control strategy and system integration technology are put forward with the purpose of improving efficiency and ensuring safety. Mechanisms underlying the influence of multi structures on the capture width ratio and frequency response width is analyzed, the effectiveness of the proposed technology for improving capture width ratio and broadening frequency spectrum is evaluated. The dynamic behavior of the device and the maximum load at each connection in extreme sea conditions are revealed and the limit conditions for the survival of the device is determined. Through theoretical and experimental studies, a way and/or a method to improve the efficiency and survivability of the device system are further revealed. The theory developed, technology innovation made and the original results obtained, including the new conceptual wave energy conversion device proposed, and the technology for enhancing survivability enhancement and improving efficiency of wave energy converter with multi-structures, multi-dimensional motion and multi-principles of energy harvesting, has important guiding significance.

本项目采用理论分析、数值模拟、物理试验相结合的方法，对由两种俘能原理系统所组成的一种新型波浪能转换装置的性能进行研究。发展该装置的多体、多维、多俘能原理系统的动力学模型理论，探索波浪驱动浮体相对转动和圆柱腔室内水体振荡的两种俘能系统的相互作用机理，提出满足该装置高效、安全运行的控制策略和系统集成技术；剖析多结构体对提高俘获宽度比和频响宽度的影响机制，评估所提出俘获宽度比增大和频响宽度拓宽技术的有效性；揭示极限波况下装置的动力学行为特征和关键节点处的最大载荷，确定装置的生存能力。所发展的理论与技术创新及获得的原创性成果对于包括所提出的该混合式波能转换装置在内的各种多体结构组成的、多维运动的和多俘能原理的装置生存力增强和效率提高，具有重要指导意义。

本项研究考虑长期部署全天候独立作业模式和深远海服役环境，海洋装备普遍存在着能源供应难和环保性差等问题，如何因地制宜提供清洁、稳定、可靠的电力成为制约海洋装备发展的“卡脖子”问题，由于波浪能是海洋能中最具有应用前景的可再生能源，研发双俘能原理波浪能转换装置的关键技术，来破解制约海洋装备发展的瓶颈问题。研究围绕着: 1)双俘能原理波浪能转换装置的模拟技术研究；2）双俘能原理波浪能转换装置的物理试验研究；3)系统集成技术及控制策略的研究。建立了双俘能效应叠加的气动式波浪能转换系统从浪至电全过程耦合的模型理论，考虑了三维流体运动、六自由度结构运动、气-液-固三体耦合，弥补现有模型误差达50%缺陷；厘清全系统中流-固-机-电相互作用机理；验证和改进模型理论，形成装置设计的理论，填补该领域国内外的空白；首次发现装置纵荡对波浪能俘获宽度比的贡献占主导地位，揭示纵荡垂荡纵摇频率各异使水柱振荡波产生叠加效应拓频增效；首创压水板，俘获宽度比CWR比提高了14%，CWR≥70%时频率响应宽度提高≥27%；发明鸭尾导流板，CWR提高了17%，CWR≥70%时频率响应宽度提高≥50%。；研制出高效U型流道透平，效率达66%，在原有53%的基础上提高了24%；揭示透平压强和流量不满足二次关系，透平的稳态设计将高估实际值；研制了首座30kW气动式波浪能发电装置，实施了以协同高效的年发电量为最大的控制策略；海试结果验证了：设计理论、拓频增效技术、高效透平技术的有效性。研究取得了预期的研究成果，发表了21篇论文，其中高影响因子的SCI论文19篇；授权的国家发明专利4项和实质审查国家发明专利1项；培养研究生9名（其中4位毕业）和博士后2名，其中1位博士生获清华大学“水木学者”。研究成果超过了预期的目标（发表论文8~11篇，其中SCI论文4～7篇；申请国家发明专利1~2项；培养研究生4~6名）。