Development of a hypercard-based graphical users interface program for implementing liquid rocket and test facility component performance models

This project involved the development of a graphical users interface (GUI) that linked a thermal properties data subroutine to liquid rocket component performance models. Three generic liquid rocket engine components were selected to demonstrate the computer program and its interactive interface. These components were a pump, a valve, and a propellant tank. The program, entitled LRE-CP², combines a modified thermophysical properties routine with a graphical user interface (GUI) using shell-based stacks created using Hypercard® software. The user enters a set of required conditions for a given component on a CRT screen in a screen specific format, and the LRE-CP² then calculates the component performance and displays it in a tabular format, both on screen and in hard copy, if desired.

Basic theory, and the format of the GUI development is discussed in detail for each component. Sample calculations are included for each component, and comparison of results with independently calculated performance is included where applicable.

In conclusion, LRE-CP² provides propulsion engineers with a convenient and easy to use graphical users interface (GUI) that integrates fluid property data into rocket or test facility component performance models. This enables component performance predictions to be obtained that are based on the best and most complete tabulations of thermodynamic state data, for 11 different fluids. Future work recommended is the development of other engine component models. In addition, the integration of the LRE-CP² into an expert design system architecture would broaden its usefulness to the rocket engine design community.