This thesis describes the modelling of thermodynamic data using Bezier curves and then the implementation of these curves within a compressible flow code. Several codes were written to use estimated Bezier points, to decrease the error in a curve modelling the specific heat of the desired species until the desired accuracy was obtained, or an optimization of the errors occurred. These curves were then integrated to find the Bezier curves for the thermodynamic properties enthalpy and entropy.
Analysis of the resulting curves revealed that there were several sources of error during the modelling process. These included small fluctuations in the experimental data, the dependency effect of neighbouring Bezier points at regions of high temperatures and the Bezier curves inability to model sharp angles. It was noted that when comparing the Bezier curves with the previously used model, both curves differed quite significantly at high temperatures. This variation was due to different assumptions made with regards to the high temperature electronic states, and has been discussed within this thesis.
These curves were then used in three flow geometries to compare the formulated Bezier curves to the previous set of data that have been used within the compressible flow code to model flow regimes including a mixture of perfect gases and nonequilibrium flow. These comparisons showed that the Bezier curve data modelled the flow as competently as the previous model at the same temperature range, but also that the newly formulated Bezier curves allowed much higher temperatures to be achieved. Hence, these Bezier curves will allow the compressible flow code to be used in cases where it was previously impossible due to the high temperatures involved, with relatively the same degree of accuracy as provided by the previous model. Therefore, the Bezier curves developed in this thesis have provided an extended model for the determination of the thermodynamic properties at high temperatures that correlates well with the previous model and other flow codes.