Generalized Entities: A Modern Framework For Rotor Dynamics Software
Swanson, E.E., and Pulitzer, S.W. III, 2002
Presented at the 2002 IFToMM Sixth International Conference on Rotor Dynamics.
Traditionally, the organization of the data for rotor dynamics software has been centered about the needs of the analysis routines. This paper offers a new approach based on a self-organizing description of the rotor(s) and stator(s). The strategy is straightforward to implement and understand, and provides a more intuitive way to model a rotor system. The concept of a Generalized Entity forms the core of the approach. Within the proposed framework, the various components that comprise rotor systems, such as point masses and bearings, are represented as similar objects with different parameters. All of the information describing how an entity interacts with the user and the model is encapsulated within in. As a result, the code is inherently modular, and newly defined entities can be added with very little programming effort. Additionally, complicated entities such as those with mixed degrees-of-freedom (e.g. mechanical and electrical) or nonlinearities can be included with few changes to the master code. This paper demonstrates the approach by discussing three examples in detail: a point mass, a conical element, and a linear bearing. It is shown how this approach can be used as the basis for a modern, self-organizing, modular rotor dynamic code.