Visualizing thermodynamic stability and phase equilibrium through computer graphics

In a landmark paper, J. W. Gibbs introduced a fundamental thermodynamic surface for pure materials and, later, expanded that analysis to mixtures. While Gibbs certainly had images of these surfaces in his mind, he described them in words rather than drawings. Since Gibbs time, a number of researchers have produced representations of these surfaces, but their studies have been limited because of the difficulty of creating and visualizing the data sets required. In this work, computer graphics has been used to visualize a variety of these models for pure, binary, and ternary systems.;Fundamental-equation surfaces produced from Legendre transforms of the energy function are well suited to illustrate the criteria for phase equilibrium through contact structures: ;Equation-of-state surfaces derived from first derivatives of ;The data sets were generated by a program developed specifically for this work. The program reads an input file that specifies the thermodynamic variable mappings, the ranges, and the quatitities to be held fixed. One extensive variable is held constant to scale the data, and for mixtures, (n-1) intensive variables are fixed so that the surfaces can be plotted in three dimensions.;Recommendations are given for extending this work to systems containing both solid and fluid phases, to mixtures displaying complex critical behavior, and to reacting systems.