Detailed bond graph models of turbomachinery

Most of studies on the unsteady characteristics of turbomachinery have been carried out using experiments, and there are few studies on methods of predicting their characteristics precisely. The bond graphs method, which is a unified approach to represent a system combined with mechanical, hydraulic and electrical sub-systems based on the flow of energy within the system, has been used to design hydraulic systems as well as to analyze their dynamic characteristics recently. The present paper deals with the above problems during very fast transients by using bond graphs. Using the steady state characteristics of each element in a pump system has developed a mathematical model representing the dynamic behavior of the system. The digital simulation results agree well with the experimental results. This means that even with the steady state characteristics of each element in a turbomachinery system, the developed model can predict the unsteady characteristics of the system. Furthermore, a new mathematical model of a torque converter is also proposed