Application of Eight-Shaped Propellant Charge in the Ejection Seat Rocket Motor

 

Milorad Savković

 

In this paper a solution for cylindrical propellant charge with the cross-section in the shape of number eight has been analyzed. A mathematical expression for calculating the burning surface area change as a function of web burned and the charge characteristic values are included. A diagram with a propellant grain perimeter change as a function of the geometric values defining the charge has been included as well. As an example concerning a solution for the eight-shaped propellant charge of the ejection seat rocket motor, an inner-ballistic calculation of thrust is presented. The calculation results have been compared to the thrust measurement results obtained during static testing of an experimental rocket motor. The experimental and calculated thrust values have shown a good agreement.

Key words: rocket motor, propellant charge, burning surface, thrust, ejection seat, pilot seat.