一种高效海洋温差能发电循环的性能分析

Study on Performance Analysis of the High-efficiency OTEC Cycle

海洋温差能是一种环境友好型、可持续利用的清洁能源,但是较低的海洋温差能发电系统效率阻碍了海洋温差能发电的商业化应用。提出一种新式循环,采用氨水混合工质,以及贫氨溶液回热和中间抽汽回热方式,实现对贫氨溶液及乏汽的热量二次回收利用。基于能量守恒方程和热力学定律,通过对循环中各设备部分建模分析,构建了新循环的热力模型,并与海洋温差能发电常用循环——朗肯循环进行性能对比分析,结果表明,新循环的热效率与净输出功相比朗肯循环均有显著提高,循环热效率最高可达4.565%,相较朗肯循环提高了25.9%。15 kW等级海洋温差能发电系统中,新循环的净输出功为7.038 kW,高于朗肯循环中的5.343 kW。新循环模型的建立及由此得到的各部分性能分析结果,可为海洋温差能商业化开发提供基础数据理论支撑。

The ocean thermal energy is an eco-friendly and sustainable clean energy,and yet its low system efficiency impedes its commercial application of the ocean thermal energy conversion(OTEC).In this study,we proposed a new cycle with regeneration and vapor extraction processes,which uses ammonia-water mixture as working fluid.By analyzing and modeling the each part of the cycle,we constructed the thermodynamic model of the new cycle,based on the energy conservation and Thermodynamic theory.Compared to the basic OTEC cycle—Rankine cycle,the thermal efficiency and net output power of the new cycle is significantly higher.The thermal efficiency of the new cycle is up to 4.565%,which is 25.9%higher than that of Rankine cycle.Moreover,under the same turbine output power and simulation conditions,the net output power of the new cycle is 7.038 kW,which is higher than that of the Rankine cycle(5.343 kW).Through the performance analysis of the simulation model for the proposed OTEC cycle,it will provide basic design data for development and utilization of an OTEC system.