基于太阳能和双有机朗肯循环的液态空气储能系统特性研究OA北大核心CSTPCD

In order to solve the problem of incomplete utilization of waste heat in traditional solar thermal storage liquid air energy storage systems(LAES-S)and further improve the round-trip efficiency of the system,a liquid air energy storage system(LAES-S-O)coupled with solar thermal storage and a dual Organic Rankine Cycle on the basis of the LAES-S system is developed.The thermodynamic model of the coupled system is established,and the influence of key parameters on system performance is analyzed.The results show that the net output power of subsystems ORC1 and ORC2 is 1 296 kW and 6 695.83 kW under typical operating conditions;the round-trip efficiency of the new system can reach 117.63%;the exergy efficiency is 38.97%;and the energy efficiency is 28.88%,which are 12.58%,2.35%,and 1.21%higher than those of the reference system,respectively.In addition,the system provides domestic hot water at a temperature of 364.15 K to the users,achieving cogeneration efficacy.Sensitivity analysis of key parameters shows that when the liquefaction pressure(compressor outlet pressure)increases from 15 MPa to 18 MPa and the liquefaction temperature(throttle inlet air temperature)rises from 93.15 K to 113.15 K,the air liquefaction rate,round-trip efficiency,and exergy efficiency decrease with the increase of liquefaction pressure,and the increase of liquefaction pressure and temperature is not conducive to the system performance;however,when the exhaust pressure increases from 5.3 MPa to 7.7 MPa,the round-trip efficiency and the exergy efficiency increases.The research results can provide some theoretical support for the liquid-air-coupled solar system.