海洋温差能发电系统新型热力循环理论分析

 海洋温差能发电系统新型热力循环在Kalina循环基础上增加贫氨溶液回热支路和抽气回热支路以提高热力循环效率。应用能量守恒原理和热平衡方程对新型热力循环--国海循环进行理论研究，计算了不同的透平入口蒸汽压力、氨水混合工质浓度、温海水温度和冷海水温度条件下的循环效率。理论计算结果表明，氨水混合工质浓度对国海循环效率影响显著，冷热源温度确定的条件下存在最优的氨水混合工质浓度使得循环效率最高，当温、冷海水温度分别为26、5℃，氨水工质浓度为92%时，系统效率最大达到4.56%；当氨水混合物浓度不变时，循环效率随透平入口蒸汽压力的升高先升高后降低，存在极大值；冷海水入口温度对循环效率影响很明显，而温海水温度对循环效率影响较小。

Theoretical analysis of a novel thermodynamic cycle for ocean thermal energy conversion

In the new type thermodynamic cycle for the ocean thermal energy conversion system, the Guohai cycle, a lean ammonia solution and the steam extraction of the turbine heat recovery branch on the basis of the Kalina cycle are adopted in order to increase the thermodynamic efficiency. This paper applies the principle of the energy conservation and the equation of the heat balance to calculate the efficiency of the Guohai cycle under different steam pressures at the turbine inlet, in warm and cold water temperatures, and with various concentrations of the working fluid. The results show that the concentration of the ammonia and water mixture has a significant effect on the efficiency. When the temperatures of the cold and warm source are fixed, there is an optimal concentration of the ammonia and water mixture, with a higher cycle efficiency. If the temperatures of the surface warm water and the deep cold water are 26 and 5℃, respectively, the maximum efficiency of the system is 4.56% as the concentration of the ammonia and water is 92%. The cycle efficiency first increases and then decreases with the increase of the steam pressure at the turbine inlet, with a maximum value in-between. The deep cold water temperature has an influence on the cycle efficiency, while that of the surface warm water has little effect on the cycle efficiency.