单耗分析理论与结构系数法的对比分析

本文简要阐述了结构系数法和能源利用的单耗分析理论,并针对链式系统进行了初步的对比分析;尽管都是基于热力学第二定律的分析方法,并且它们的结果有一定的相似性,但结构系数法存在某些错误。比较而言,单耗分析理论显得更全面,也更实用。本文以锅炉供热系统为对象进行了详细的单耗分析,对系统中间子系统的(火用)耗损变化所带来的影响进行了详细的分析,结果证明结构系数法所作的“某一子系统(火用)效率变化,其他子系统(火用)效率不变”的假设是不恰当的, 其结论也是不准确的。

COMPARISON OF THE THEORY OF THE UNIT FUEL CONSUMPTION ANALYSIS AND THE METHOD OF STRUCTURAL COEFFICIENTS

The method of structural coefficients and the theory of the unit fuel consumption analysis of the energy utilization systems are concisely explained and compared for the chain system in the paper. Although both of them are the methods based on the second law of thermodynamics and their results have some comparability also, the method of structural coefficients has some errors. The theory of the unit fuel consumption analysis is more integrated and practical than the method of structural coefficients. The case study of the unit fuel consumption analysis of the boiler-group heating system is given in the paper. The effect of the exergy loss change of the hot water network subsystem in the heating system on the total unit fuel consumption is analyzed in detail. The result of the case study proves that the hypothesis of the method of the structural coefficients, "the exergy efficiency of a subsystem changes and the exergy efficiencies of the other subsystems remain unchanged", is improper and that its conclusion is inaccurate also.