基于振荡水柱的海洋温差能综合高效利用机理研究

Using abundant ocean renewable resources for power generation and desalination has become an important way for human to solve the shortage problems of freshwater resources and energy and to protect the Earth's environment. The new ocean energy utilization system is based on the Oscillating Water Column(OWC) wave energy utilization technology and the Ocean Thermal Energy Conversion(OTEC) technology and supplys stable electricity and produces fresh water through the pressure-maintaining storage device.. The system theoretically not only overcomes disadvantages such as too much self-consuming power, which are used in both the making of negative pressure and the transport of warm water and cold water, sea creature attachment, and huge turbine requirements because of small pressure between the evaporator and condenser in Open Cycle OTEC system, but also overcomes disadvantages of poor efficiency in the OWC wave energy utilization technology because of instable wave energy. Theoretically, the system can improve the energy flow density, and achieve comprehensive and high efficient use of wave energy and ocean thermal energy for power generation and desalination. The theoretical analysis, numerical simulation and experimental modeling methods are used to study the relationship between the OWC chamber's pressure and the rate of sea water evaporation, the relationship between warm water's temperature and the rate of sea water evaporation, the mode selection and mechanism of the pressure-maintaining storage device, and the atomization process of the OWC chamber,etc. The study's final goal is to optimize the design of the system and improve the energy conversion efficiency and the fresh water production rate. The results of the present study will supply theoretical guidance, basic data and experiences for the optimal design of the comprehensive utilization system which is based on the OWC technology and OTEC techbology.

利用丰富的海洋能进行发电和海水淡化是人类解决淡水资源和能源短缺、保护地球环境一条重要途径。本课题海洋能利用系统理念是基于振荡水柱波浪能利用技术，结合温差能发电特点，通过蓄能稳压装置，输出稳定的电能和生产淡水。该系统原理上不仅克服了目前温差能开式循环发电系统中温、冷水海水输送和负压形成自耗大、海生物附着、蒸发器和冷凝器之间压差小透平要求大等缺点，又可服了振荡水柱波浪能利用技术中能量不稳定导致发电效率低的缺点，提高了利用系统能量来流密度，实现了波浪能和温差能共同作用下发电和海水淡化综合高效利用。课题采用理论分析、数值模拟和物模实验方法研究振荡水柱气室气压、温海水温度同海水蒸发率的关系、蓄能稳压方式选择及机理，振荡水柱气室雾化工艺等，其最终目的是优化利用系统，提高能量转换效率和淡水产出率。课题的研究成果为基于振荡水柱的海洋温差能综合利用系统的优化设计提供基础数据和科学依据。

利用丰富的海洋能进行发电和海水淡化是人类解决淡水资源和能源短缺、保护地球环境一条重要途径。然而面对恶劣的海洋环境，人类开发海洋能源举步艰难、成本昂贵。本课题基于单浮体振荡水柱波浪能转换技术结构简单、转换效率高、吃水浅的特点，结合成熟的船舶技术，发展了一种自航式海洋资源利用技术。该技术以船舶为载体，以波浪能和海洋温差能为“燃料”，采用移动或定点方式采集海洋能，输出电力和淡水。该技术利用了多种海洋可再生能源，攻克了目前波浪能转换技术存在的转换效率低、生产成本和海洋工程费用高、台风破坏等世界难题。课题组成员深刻认识到减少四周遮挡和减少造波损失是提高漂浮振荡水柱能量转换效率的两个重要途径，即波能装置的“开源”“节流”措施。改进的模型实验证明单浮体后弯管振荡水柱技术在随机波中从波浪能量到气动能量转换效率高达87.2%，达到国际领先水平。依据热力学循环理论研究了做功工质的物性，设计和制造了一套不稳定能源温差能海水淡化模拟装置。实验研究表明，当闪蒸室气压控制在2.6~3.3kPa、温、冷海水进口温度分别为24.8℃与 22.3℃时，模拟装置淡水产出率为1.05kg/h；当温、冷海水进口温度分别为26.1℃与 16.5℃时，模拟装置淡水产出率为3kg/h。研究成果为海洋小温差热能利用打下了基础。设计和研建了1kW自航式波浪能发电装置，实现了自航。1kW自航式波浪能装置河试成功，为海上绿色能源装置进港避台风、现场维护和广海域利用海洋绿色能源提供了技术基础，在低成本、高效、安全利用海洋绿色能源技术上迈出了重要一步。未来装置上除了波浪能发电设备外，还可安装风力发电设备和太阳能集热设备，综合利用效益更高，也使远海绿色能源利用变成了可能。整个系统就是一座自航式资源供应站。本课题发表学术论文19篇，其中SCI/EI论文5篇。申请发明专利4项，其中授权1项。研建了1套1kW后弯管振荡水柱发电样机1套。培养学生4名。