太阳能辅助燃煤一体化热发电系统耦合机理

在系统中沿过程进行的方向火用具有不等价性。外部键系数作为一种结构系数,在用于揭示系统内在的热力学联系、分析不等价性时具有明显的优越性。利用信号流图理论,探讨了外部键系数的计算方法,得到不同容量燃煤机组不同流的外部键系数。揭示了太阳能辅助燃煤一体化热发电系统的耦合机理：不仅要遵循能量"品位对口、梯级利用"的原则,而且还需考虑外部键系数的大小;只有当太阳能热量用于取代燃煤机组中外部键系数高的火用流时,取得的效益才大。

Coupling Mechanism of Solar Supported Coal-fired Electric Generation System

In a system, non-equivalence is an inherent performance of exergy in the process. To analyze this performance, coefficient of external bonds (CEB), as a structural coefficient, should be utilized as well as to find the internal thermodynamic correlation. The calculating method of CEB was discussed based on signal flow diagram theory, consequently the CEB of different flows in different coal-fired units was obtained. Furthermore, the coupling mechanism of solar supported coal-fired electric power generation systems was given: the principle of energy, i.e. reasonable quality matching and cascade utilization, should be followed, at the same period, the value of CEB also should be considered. The results show that better effects could be achieved only when high CEB exergy flow of coal-fired units is replaced by solar heat.