摘要
膨胀机作为压缩空气储能系统释能环节的主要部件,其效率及运行特性对整体性能具有决定性影响。与绝热膨胀相比,等温膨胀是提高活塞式膨胀机输出性能的有效方法。利用高温水雾喷入气缸强化缸内气体换热,进而提高膨胀做功能力。为了研究喷雾换热对膨胀过程的影响,首先建立了活塞式膨胀机绝热膨胀的非线性数值模型,并通过实验结果验证了模型的准确性。其次引入水雾-空气的传热方程,建立了准等温膨胀的非线性数值模型。仿真表明:进气压力1 MPa,负载扭矩30 N·m时,准等温膨胀的缸内平均空气温度提高了56 K,输出功率降低了1.48%,效率降低了3.63%。通过压力-容积图可知,准等温膨胀提高了膨胀阶段的缸内气体压力也导致了排气阶段气体背压的增加。
As the main component of energy release of compressed air energy storage system,the efficiency and operating characteristics of expander have a decisive influence on the overall performance.Compared with adiabatic expansion,isothermal expansion is an effective method to improve output performance of piston expander.The high temperature water mist is sprayed into the cylinder to strengthen the heat exchange of the gas in the cylinder,so as to improve g the expansion work capacity.To study the effect of spray heat exchange on the expansion process,a nonlinear numerical model of adiabatic expansion of a piston expander is firstly established in this paper,and the accuracy of the model is verified by experimental results.Secondly,the nonlinear numerical model of quasi-isothermal expansion is established by introducing the water mist-air heat transfer equation.Simulation results show that when the inlet pressure is 1 MPa and the load torque is 30 N·m,the average air temperature in the cylinder of the quasi-isothermal expansion is increased by 56 K,the output power is reduced by 1.48%,and the efficiency is reduced by 3.63%.By analyzing the pressure-volume diagram,it can be seen that the quasi-isothermal expansion increases the in-cylinder gas pressure in the expansion phase also leads to an increase in the gas back pressure in the exhaust phase.
作者
虞启辉
李晓东
YU Qi-hui;LI Xiao-dong(School of Mechanical Engineering,Inner Mongolia University of Science&Technology,Baotou,Inner Mongolia 014010;Beijing Key Laboratory of Pneumatic Thermal Energy Storage and Energy Supply Technology,Beijing 100191)
出处
《液压与气动》
北大核心
2023年第9期75-84,共10页
Chinese Hydraulics & Pneumatics
基金
国家自然科学基金(52065054)
北京高等学校卓越青年科学家计划(BJJWZYJH01201910006021)。
关键词
活塞式膨胀机
准等温膨胀
输出性能
温度
背压
piston expander
quasi-isothermal expansion
output characteristics
air temperature
back pressure
