Computer-Aided Analysis of Gas Turbine Cycles

Abstract

This paper describes a microcomputer-based, interactive, and menu-driven software package designed to help mechanical engineering students to understand gas turbines and to allow them to conduct more analysis of gas turbine cycles than they would normally be able to do by hand-calculation. The program deals with gas turbine cycle analysis so the acronym GTCA is used. GTCA is written in the Pascal computer language and runs on IBM PC, or compatible, computers. Improvements to the basic Brayton cycle, including three compressor and turbine stages, reheater, heat exchanger, intercooler, and precooler are incorporated into the program. The package is highly flexible and allows the user to model cycle schemes formed of any combination of these elements and to handle both shaft power turbines and aircraft turbojet and turbofan turbines. An important feature of the program is its ability to solve for any unknown variables. In addition to this, the program provides a schematic of the turbine plant layout and a temperature-entropy diagram of the cycle, and permits the plotting of the variation of any quantity versus any other quantity. This option enables the student to easily study and understand the effects of changing design variables on the overall performance of the cycle and permits its optimization. The statistical survey conducted along with the examples presented demonstrate the capabilities of the package as a teaching tool.