Session: 08-01 Education Issues I

Paper Number: 82041

82041 - A MATLAB Based Set of Functions for Finding Thermodynamic Properties and Solving Gas Turbine and Other Thermodynamics Problems 

A new set of MATLAB based functions have been written for providing fluid property data and solving thermodynamics problems.  One function, named realprop, utilizes NIST property tables for pure real fluids (e.g. water, various refrigerants, propane, etc.), and provides desired properties when provided with any two other independent properties.  Properties can be obtained for liquids, vapors, and two-phase mixtures.  Another function, named igprop, provides properties for a range of pure ideal gases using NASA functions for specific heats.  Enthalpies are referenced to include the heat of formation, so the function is useful for solving combustion problems.  A third function, named airprop, utilizes the igprop function to provide ideal gas properties for dry air, assuming a mixture of 78% N₂, 21% O₂, and 1% Ar by volume.  A fourth function, named psycprop, uses the airprop and realprop functions to provide properties for moist air.  Additional functions are available to generate property plots, including temperature-entropy, enthalpy-entropy, and pressure-volume plots, as well as psychrometric charts.  All functions can be used with the SI or the U.S. Customary unit systems.  The package has been successfully used in the second of two required thermodynamics courses at the author’s institution, with incorporation into all aspects of the course, including homework, laboratories, design exercises, exams.  When used in conjunction with built-in MATLAB routines, the new functions are useful for parametric and optimization studies.  The full package, including function codes and data files, requires 2.5 MB of disk space.  It requires access to MATLAB, but is otherwise available at no cost.  The paper will present the functions and provide examples of their use for solving various types of problems.

Presenting Author: Ralph Volino United States Naval Academy

Presenting Author Biography: Professor, Unites States Naval Academy since 1995. Fellow ASME.

Authors:

Ralph Volino United States Naval Academy