PARAMETRIC SENSITIVITY ANALYSIS OF CONVEX STAR PORT PROPELLANT GRAIN FOR SOLID ROCKET MOTOR

Aqeel Nawaz, Muhammad Ali Kamran

Abstract


Grain design takes the central place in a solid rocket motor design activity. Ballistic quality of a designed grain can be evaluated by two vital indexes known as neutrality and sliver content. Sliver content results in tail-off of the thrust-time curve. These two measures of merit are an important part of acceptable grain design. This paper is restricted to the study of convex port star grain geometry and describes parametric evaluation to assess the effects of seven independent and defining geometric variables of the star and other ballistic factors including density of propellant and characteristic exhaust velocity on the burn pattern and performance profile for qualitative analysis of sliver fraction (tail-off)and neutrality. The purpose of the study is to expand the design domain by evaluating entire convex Star family under both neutral and least sliver content conditions. The computer program associated to it is essentially the ballistic design analysis of the convex star grain configuration. Results showed that neutrality and sliver fraction are dependent on certain parameters. It has been observed that for good neutrality, higher angular fraction and star angle close to neutrality must be maintained. Sliver fraction depends upon the star geometry and can be reduced by decreasing angular fraction leading to reduced tail-off. Thus neutrality and reduced tail-off cannot be achieved simultaneously and trade-off has to be made. However, higher value of characteristic exhaust velocity (C*) will reduce tail-off.


Keywords


Grain design; tail-off; ballistic design; neutrality

Full Text:

PDF

References


O. Biblarz and G. P. Sutton, Rocket Propulsion Elements: Wiley, 2011.

F. Dauch and D. Ribereau, "A Software for SRM Grain Design and Internal Ballistics Evaluation, PIBAL," 2002.

M. Johannsson, "Optimization of Solid Rocket Grain Geometries," KTH, 2012.

R. Hartfield, R. Jenkins, J. Burkhalter, and W. Foster, "A review of analytical methods for solid rocket motor grain analysis," AIAA Paper, vol. 4506, 2003.

Antoine Lefebvre, "Burning analysis of star configuration. ," October 27, 2000. Retrieved from http://rocketworkbench.sourceforge.net/

W. Brooks, "Application of an analysis of the two-dimensional internal-burning star grain configuration," in AIAA, SAE, and ASME, Joint Propulsion Conference, 16 th, Hartford, Conn, 1980, p. 1980.

A. RICCIARDI, "Complete geometrical analysis of cylindrical star grains," in AIAA, ASME, SAE, and ASEE, Joint Propulsion Conference, 25 th, Monterey, CA, 1989, p. 1989.

S. P. G. Design and I. Ballistics, "NASA/SP-8076," NASA (March 1972), 1972.


Refbacks

  • There are currently no refbacks.


Copyright (c) 2017 Journal of Engineering and Applied Sciences (JEAS), University of Engineering and Technology, Peshawar

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

ISSN: 1023-862X  & eISSN:2518-4571