Experimental and theoretical study on a dual-thrust rocket motor with subsonic intermediate nozzle

Abstract

Dual-thrust rocket motors, with proper designs, can yield the desired boost-sustain thrust profiles for a variety of applications. Of the various designs that a dual-thrust rocket motor can have, the one with an intermediate nozzle provides a high boost-to-sustain thrust ratio as well as a stable operation. Depending on the internal conditions, the flow through the intermediate nozzle in the boost phase can be sonic, subsonic, or initially reversed. The present paper discusses the operation and performance of Dual-thrust rocket motors with subsonic intermediate nozzle. A mathematical model describing the internal ballistics of these dual-thrust rocket motors is derived from the basic governing equation. In addition, a set of experiments is conducted using a developed test motor to explore the physics of dual-thrust rocket motors with subsonic intermediate nozzle and assess the mathematical model validity. Results of the theoretical and experimental investigations explain most of the internal ballistics characteristics that were not discussed before in the open literature.

Keywords

Solid propellant rocket propulsion dual-thrust rocket motor thrust ratio intermediate nozzle static firing tests

Get full access to this article

View all access options for this article.

References

Sutton

. Rocket propulsion elements, 7th ed. New York: John Wiley& Sons, Inc., 2001.

Darwell HM. Solid propellant dual-thrust motors. In: Proceedings of the 1st rocket propulsion symposium, Cranfield, Plenum Press, 1961.

McFillin

Van Brocklin

Beakley

et al.

Dual-chamber Roicekt motor operating characteristics. J Spacecraft Rockets 1984; 21: 168–174.

Carrier

Constantinou

Harris

et al.

Dual-interrupted-thrust pulse motor. J Propul Power 1987; 3: 308–312.

Manda

. Boost-phase equilibrium pressures in a dual-thrust soil-propellant rocket motor. J Spacecraft Rockets 1965; 2: 607–609.

El-Nady AM. Theoretical and experimental investigation of a dual-thrust rocket motor with an intermediate nozzle. PhD Dissertation, Military Technical College, Egypt, 2015.

El-Nady AM, Sarhan AM, El-Sanabawy MA, et al. Investigation of dual-thrust rocket motor with subsonic intermediate nozzle. In: 51st AIAA/SAE/ASEE joint propulsion conference, Orlando, FL, USA, 27–29 July 2015.

Barrerre M. Rocket propulsion. New York: Elsevier Pub. Co., 1960.

Anderson

. Modern compressible flow: With historical perspective, New York: McGraw Hill Higher Education, 1990.