Optimization of Tehrmodynamic Cycles

热力学循环的优化

基本信息

批准号：
07555387
负责人：
ITO Takehiro
金额：
$ 0.38万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07555387/
关键词：
Thermodynamic cycle HAT cycle Combined cycle Binary mixtures Combustion

项目摘要

The present study is to find out the optimum condition of various thermodynamic power cycles. The cycles we examined are the combined cycle which uses Kalina cycle as a bottoming cycle, HAT cycle and a composite power cycle to recover cold energy of liquefied natural gas (LNG). We obtained an optimum operating condition for each cycle and compared their performance with those of conventional combined cycle by gas turbine and Rankine cycle.Pure methane (CH4) was the fuel in all calculations covered and we assumed that the exit temperature of combustion chamber in open Brayton cycle ranges from 800 to 1400ﾟC.Other parameters for Kalina cycle are the ratio of flow rate of exhaust gas in topping cycle to that of working fluid in bottoming cycle, the pressure and concentration of ammonia at the inlet of turbine in bottoming cycle. On the other hand, for HAT cycle, the parameters are the air ratio in combustion chamber, the exit temperature of humidifier and the flow rate of cooling air in g … More as turbine. The amount of NO_x in each condition was obtained.The combined cycle by Kalina cycle as the bottoming brings higher performance when the temperature of heat source is relatively low, while its performance decreases when the temperature of heat source is higher. The HAT cycle enhances efficiency with less NO_x emission compared with the conventional gas turbine cycle.Finally, we examined a composite power cycle by R-13 and natural gas to recover cold energy of LNG.The R-13 cycle uses seawater as the hot heat source and LNG as the cold source. The LNG passing through R-13 cycle is heated by seawater and expands in two natural gas turbines. The parameters are the system pressure and the ratio of flow rate of R-13 to LNG.The result shows that the work produced by R-13 cycle is a half of the natural gas cycle, the increase in work by R-13 cycle will bring higher total efficiency of the combined cycle and the cycle effectiveness can be raised by decreasing the temperature difference between R-13 and natural gas in the high pressure condenser. Less

本研究是找出各种热力学动力周期的最佳条件。我们检查的周期是使用Kalina循环作为底部周期，HAT循环和复合功率周期的组合循环，以回收液化天然气（LNG）的冷能。我们获得了每个周期的最佳操作条件，并将它们的性能与燃气轮机和兰金周期的常规组合周期进行了比较。Pure甲烷（CH4）是所有计算中的燃料，我们假设在开放的Brayton周期中，组合室的出口温度范围为800至1400 c. KALINA周期的底部流动率是底层的均匀循环，而在底部的流动率是底层的流动速率。底部涡轮机入口处的氨。另一方面，对于HAT循环，参数是组合室中的空气比，在每个条件下的NO_X的出口。当热源的温度相对较低时，Kalina循环的合并循环会带来较高的性能，而当热源的温度较高时，其性能会降低。与常规燃气轮机周期相比，HAS循环以较少的NO_X排放提高了效率。在最后，我们检查了R-13的复合功率周期和天然气以恢复LNG的冷能量。R-13循环使用海水作为热热源，LNG作为冷源。通过R-13周期的LNG通过海水加热，并在两个天然燃气轮机中膨胀。参数是系统压力和R-13与LNG的流速之比。结果表明，R-13周期所产生的工作是天然气周期的一半，R-13周期的工作增加将带来较高的组合周期总效率，并且可以通过降低R-13和天然天然气体之间的高压凝聚力来提高周期效率。较少的