EBSILON与MATLAB仿真在超临界二氧化碳循环设计应用
EBSILON and MATLAB Simulation in Supercritical Carbon Dioxide Cycle Design Application
赵峰 1刘桃宏 1杜晓东1
作者信息
- 1. 上海船舶设备研究所,上海 200031
- 折叠
摘要
与同等功率级别的常规蒸汽朗肯循环效率相比,超临界二氧化碳简单回热循环效率并未体现优势,只有 35.91%.经过分析,由于回热器冷端温升较大冷端的高压流体比热容远大于热端流体,冷端流体的温升明显小于热端流体的温降,使得工质没有被预热到一个尽可能高的温度,导致所需投入的加热量依然很大,回热器效率较低;且由于冷热两端温度变化差值较大,简单回热循环易发生回热器"夹点"问题,导致传热发生恶化,进一步影响整个循环效率.为此,采用再压缩循环代替简单回热循环,研究分流比、透平入口温度、主压缩机入口压力和温度、主压缩机出口压力对再压缩循环效率的影响.结果显示:在系统输入参数确定的情况下,存在一个最佳分流比使得循环效率达到最大值,较简单回热循环效率提升 15.65%,透平入口温度和主压缩机入口温度、压力及出口压力与分流比具有一定的耦合关系,对循环效率都有影响.
Abstract
Compared with the conventional steam Rankine cycle efficiency of the same power level,the simple regenerative cycle efficiency of supercritical carbon dioxide does not show an advantage,only 35.91%.After analysis,due to the large temperature rise on the cold side of the regenerator,the specific heat capacity of the high-pressure fluid on the cold side is much larger than that of the fluid on the hot side,and the temperature rise of the fluid on the cold side is significantly smaller than the temperature drop of the fluid on the hot side,so that the working medium is not preheated to a high temperature as possible,resulting in a large amount of heating required and a low efficiency of the regenerator.Moreover,due to the large temperature difference between the cold and hot sides,the simple regenerative cycle is prone to the"pinch"problem of the regenerator,which leads to the deterioration of heat transfer and further affects the efficiency of the whole cycle.Therefore,recompression cycle is used to replace simple regenerative cycle,and the effects of split ratio,turbine inlet temperature,main compressor inlet pressure and temperature,and main compressor outlet pressure on the efficiency of recompression cycle are studied.The results show that when the system input parameters are determined,there is an optimal split ratio to maximize the cycle efficiency,which is 15.65%higher than the simple regenerative cycle efficiency.There is a certain coupling relationship between turbine inlet temperature,main compressor inlet temperature,pressure and outlet pressure and split ratio,which has an impact on cycle efficiency.
关键词
超临界二氧化碳/再压缩循环/分流比/循环效率Key words
supercritical carbon dioxide/recompression cycle/split ratio/cycle efficiency引用本文复制引用
出版年
2024
NETL
NSTL
万方数据