基于SOFC/GT/TCO2复合动力循环和溴化锂制冷机的冷热电联供系统性能

提出了一种新型冷热电联供系统，通过TCO₂循环和溴化锂制冷机回收SOFC/GT循环的排烟余热，实现对外供冷、供热和供电。建立了联供系统热力性能的数学模型，对系统进行了能量分析和（火用）分析，并研究了空燃比、SOFC压力、CO₂工质流率、CO₂工质分流比和TCO₂泵出口压力对系统性能的影响。研究结果表明，在额定工况下，系统的净发电效率为70.79%，系统总（火用）效率为68.29%，综合能源利用率为108.5%。增大空燃比、CO₂工质分流比或降低SOFC工作压力、CO₂工质流率和TCO₂泵出口压力可提高联供系统的综合能源利用率；增大SOFC工作压力、TCO₂泵出口压力或降低空燃比可提高联供系统的净发电效率和总（火用）效率，随CO₂工质流率和CO₂工质分流比的增大，净发电效率和总（火用）效率先降低后增大。

Performance of combined cooling,heating and power system based on SOFC/GT/TCO2 integrated power cycle and LiBr-water absorption chiller

A novel combined cooling, heating and power system is proposed. The waste heat of the exhaust gas from the SOFC/GT hybrid system is recovered by a transcritical CO₂ cycle and a LiBr-water absorption chiller for cooling, heating and power supply. Thermodynamic mathematical models of the CCHP system are developed, then energy and exergy analyses are used to analyze the performance of the CCHP system. The effect of air-fuel ratio, SOFC pressure, CO₂ flow rate, CO₂ split ratio and the outlet pressure of the TCO₂ pump on the performance of the entire system are studied. The results show that the overall energy utilization, the net power generation and the exergy efficiencies of the entire system can reach 108.5%, 70.79% and 68.29%, respectively, under the specified condition. The overall energy utilization efficiency can be improved by increasing air-fuel ratio or CO₂ split ratio, and decreasing SOFC pressure, CO₂ flow rate or the outlet pressure of the TCO₂ pump. The net power generation and the exergy efficiencies can be improved by increasing SOFC pressure or the outlet pressure of the TCO₂ pump, or by decreasing air-fuel ratio. The net power generation and the exergy efficiencies first decrease and then increase with the increase in CO₂ flow rate or CO₂ split ratio.