A Design Tool For Missile System Rocket Motor Scaling

Introduction Advancing computer technology has enhanced the ability to conduct conceptual / preliminary design of aircraft and missile systems more rapidly utilizing computational design tools. For the aerodynamic design, programs used range from computational fluid dynamics (CFD) to quick aeroprediction codes such as AP98, Missile Datcom', and PANAIR. This analysis must give realistic results for the conceptual / preliminary design. In order to perform a complete system analysis other tools are needed to size other components of the aircraft and missile system. One primary driver in the missile performance and sizing is the propulsion system. The propulsion system for most missile configurations is based on a solid propellant although some newer designs are utilizing gelled propellants. In this paper we introduce the tools and overall design methodology used by SAIC's missile system division in analyzing new and current missile systems. Emphasis of this paper will be given to the user-friendly design tool for the analysis of missile system propulsion. Chief Aerodynamicist, Missile System Division, Assistant Professor Aerospace Engineering, Senior Member AIAA $ Senior Scientist + Systems Engineer * Engineering Intern, Georgia Tech Copyright©2000 by SAIC. Published by the American Institute of Aeronautics and Astronautics, Inc. with permission. In performing conceptual / preliminary design or analysis a small staff with a quick turnaround time is the norm. This implies that accuracy in the computational tools is essential. These tools include quick aeroprediction codes, mass property calculators, structural analysis, and propulsion analysis capabilities. The first step in all the analysis work starts with a base missile/projectile design. This design may be a new conceptual configuration or an enhancement to a current missile or projectile. Upon establishing the structural configuration the aerodynamics are calculated. Typical computational tools used for this portion range from computational fluid dynamics (CFD) to quick aeroprediction codes such as AP98 and Missile Datcom'. After utilizing these tools for the aerodynamic characteristics the next step is to fly the preliminary or modified design in a 3 degree-of-freedom or 6 degree-of-freedom analysis to ensure that the vehicle can perform the desired task. Before this analysis can take place the propulsion system analysis must also be performed. This analysis must give realistic results for the preliminary design. In some cases these designs are modifications of current missile systems, therefore the propulsion system may be slightly modified to meet the new design parameters. In this paper we present a user-friendly design tool for the analysis of missile system propulsion systems. This first version of the rocket motor scaling routines program is capable of basic rocket motor scaling and performance parameter prediction and estimation. By inputting specifications for an existing motor and specifying various 1 American Institute of Aeronautics and Astronautics (c)2000 American Institute of Aeronautics & Astronautics or Published with Permission of Author(s) and/or Author(s)' Sponsoring Organization.