离心式CO_(2)逆布雷顿制冷系统的[火用]分析研究  

Exergy Analysis of CO_(2) Centrifugal Reverse Brayton Cycle

作　　者：周娇乐 李昊 王厉 Zhou Jiaole;Li Hao;Wang Li(School of Civil Engineering and Architecture,Zhejiang Sci-Tech University,Hangzhou,310018,China)

机构地区：[1]浙江理工大学建筑工程学院,杭州310018

出　　处：《制冷学报》2024年第4期93-103,共11页Journal of Refrigeration

摘　　要：离心式逆布雷顿循环(CRBC)是一种利用离心力势能-压力能转换的制冷循环,工质在旋转管内的离心和向心流动实现高效压缩和膨胀过程,为提升气体制冷循环的效率提供了潜在可能性。以CO_(2)为制冷工质,水为冷却介质,建立了离心式逆布雷顿制冷系统的热力学模型,并进行[火用]分析,研究系统的[火用]效率及[火用]损分布情况,为系统的评估及改进提供理论依据。研究结果表明:在相同送风温度下,加热器进口温度存在优化可能,系统最大[火用]损率出现在离心等温压缩、绝热压缩和向心绝热膨胀流动过程,分别约为20%,空气冷却过程和离心绝热压缩流动过程的[火用]损率较小且与加热器进口温度呈相反的变化趋势。离心式逆布雷顿循环的[火用]效高达19.2%,远高于CO_(2)逆布雷顿循环的8.1%、开式空气逆布雷顿循环的4.9%和闭式空气逆布雷顿循环的2.3%。The centrifugal reverse Brayton cycle(CRBC)is a novel refrigeration cycle that harnesses the conversion of inertial potential energy to pressure energy,enabling efficient compression and expansion processes through centrifugal and centripetal flows of the working fluid within a rotating tube.This offers a promising potential for improving the refrigeration efficiency of conventional gas refrigeration cycles.Building on previous studies,this study employs a thermodynamic model to conduct a parametric analysis of the CRBC to explore the thermodynamic efficiency and loss distributions of the cycle,providing a theoretical foundation for system evaluation and enhancement.Results show that,under the same inlet air temperature,an optimization possibility exists for the heater inlet temperature.The system experiences substantial exergetic losses during the centrifugal isothermal compression flow,adiabatic compression,and centripetal adiabatic expansion flow,each at approximately 20%.Conversely,the exergetic losses during the air-cooling process and the centrifugal adiabatic compression process are comparatively low and demonstrate an inverse relationship with the inlet temperature of the gas heater.The exergetic efficiency of the CRBC reaches 19.2%,which significantly surpasses the values of 8.1%for the CO_(2) reverse Brayton cycle,4.9%for the open-air reverse Brayton cycle,and 2.3%for the closed-air reverse Brayton cycle.

关 键 词：逆布雷顿循环 CO_(2)制冷循环 超重力场 [火用]分析 

分 类 号：TB611[一般工业技术—制冷工程] TB614