文献类型：期刊文献

中文题名：物系∪环境模型——负压系统问题及解法

英文题名：The Dead State Thermodynamics Dealing with Vacuum Systems: Problems and Solutions

作者：关俶[1]

机构：[1]华东化工学院石油加工系

年份：1989

卷号：15

期号：1

起止页码：12

中文期刊名：华东化工学院学报

收录：Scopus;CSCD:【CSCD2011_2012】；

语种：中文

中文关键词：物系U环境;负压物系

外文关键词：thermodynamic model; the 2nd law analysis; energy; exergy; energy transfer

摘要：讨论了用寂态热力学方法处理负压系统时,将会遇到的三类难题:闭系中(火用)大于内能,(火无)为负值;稳流物系条件下,(火用)出现负值,(火无)大于焓;能级计算时可能出现正、负无限大值。指出它们来源于(火用)概念的内在矛盾及能级定义的不确切性,可以用‘物系∪环境’模型加以解决。论证了新的环境概念,指出(火用)值为零的状态唯一地对应于寂态,从而消除了负压稳流物系的所谓‘环境线’。提出了‘大系统最大输出能能级最小,最小可逆输出能能级最大’原理,根据这项原理,给出了推导‘负压物系∪环境’有关参数表达式的方法。
There are three difficult cases often encountered in the dead state thermodynamics when vacuum systems are dealt with: 1) with closed systems, Ex>U,An<0; 2) with open systems, Ex<0, An>H; 3) in 'energy level', the value Calculated may approach±∞ when calculated by use of the formulas Ω= Ex/U (for closed systems) and Ω= Ex/H (for open systems). All of these problems can be solved by use of the composite system model, SYS∪ENV. According to this model, the relevant environment of the system may act as an 'exergy reservoir' or a 'secondary exergy resource' without violating the second law; based on the new concept of 'environment', the state of the system with zero Ex corresponds to the dead state uniquely.A new principle is demonstrated which says: 'the maximum energy outflow from the composite system includes the maximum anergy outflow, reaching the minimum energy level, while the minimum reversible energy outflow includes the minimun energy outflow, reaching the maximum energy level'. An example is given to illustrate how to use the principle to derive the expressions for the properties of the composite system.