REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

Analytical and numerical burnback analysis of End Burner grain with CYLINDRical cavity

Mohammed Alazeezi

Ph.D. student, University of Belgrade – Faculty of Mechanical Engineering, Belgrade
Emirates Advanced Research & Technology Holding LLC, Abu Dhabi, mohammed.alazizi@earthuae.ae

predrag elek

University of Belgrade – Faculty of Mechanical Engineering, Weapon Systems Department, pelek@mas.bg.ac.rs

Abstract: Burnback analysis is a critical stage in the design of solid propellant rocket motors. This paper will focus on investigating the burnback analysis of an end burner grain with central cylindrical cavity. Analytical and numerical methods for evaluating the burning surface area have been used. The analytical geometrical equations that illustrate the burning surface area evolution were developed for the two-phase burning process. The first phase is the boost phase and the second phase is the sustaining which lasts longer. A parametric model of the grain was also created in PTC Creo to simulate the burn back numerically. The results from both methods show an agreement which approves that the numerical method could be used for complex grain shapes, for which it is difficult to obtain the analytical solution.  Furthermore, a MATLAB program was developed in order to compare the numerical and analytical results and to predict some of the main interior ballistics parameters.

Keywords: burnback, solid propellant grain, burning surface area, rocket propulsion