Second law analysis revisited: a critical look at its past development, a clarification of its terminology, and a demonstration of its use as a design tool through microcomputer programming

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Virginia Polytechnic Institute and State University


The second law is still rarely used as a design decision tool. However, information obtained from second law analysis is valuable in the design process for thermodynamic systems.

This investigation reviews the past development of second law analysis. A clear, operational vocabulary is established. Then two examples of microcomputer-based design procedures are presented. The first is a second law analysis of refrigeration cycles. As a part of this example, the correlation of physical property data by simple methods is demonstrated. The second example is a second law analysis of gas turbine systems.

The salient point is that all of this can be done on a microcomputer, and consequently is readily available to any engineer.