• Journal of the Korean Society of Propulsion Engineers
• /
• v.19 no.2
• /
• pp.1-8
• /
• 2015

Dual pulse rocket motor is a variant of solid rocket motor with two propellant grain separated by a pulse separation device. The major performance of such a rocket motor is influenced by the change in the hole area of pulse separation device to nozzle throat area ratio. In this study, we performed flow analysis to investigate the internal flow characteristics according to the pulse separation device hole area to nozzle throat area ratio change. Gases used flow analysis were used combustion gas of HTPB/AP composite propellant and nitrogen gas. Flow analysis results of the dual pulse rocket motor were validated by comparison with experimental results of pneumatics. Commercial CFD code ANSYS FLUENT 14.5 is used in this study to simulate flow analysis.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.11a
• /
• pp.820-824
• /
• 2010

The purpose of this study is to develop basic technology of hybrid rocket vehicle by constructed and launched. This small hybrid rocket using HDPE/LN2O and Aluminium steel for its body (weight : 12.5 kg, diameter : 114 mm, height : 1.8 m) was designed. The fuel grain and injector were designed for 50 kgf thrust and burning time 2.5 sec. This rocket was loaded the data acquisition device for obtaining data of pressure and velocity during its flying and equiped an automatic ejector system using spring/motor and timer to collect the rocket more safely after launching. It was launched successfully, but found some problem that the rocket's weight was heavier than expected and the thrust was not enough to reach the designed altitude and analyzed its flight path way.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2007.04a
• /
• pp.233-237
• /
• 2007

Recent experimental data shows that an irregular fuel surface pops up during the combustion test. This may contribute to the agitated boundary layer due to blowing effect of fuel vaporization. Blowing effect can be of significance in determining the combustion characteristics of solid fuel within the oxidizer flow. LES was implemented to investigate the flow behavior on the fuel surface and turbulence evolution due to blowing effect. Simple channel geometry was used for the investigation instead of circular grain configuration without chemical reactions. This may elucidate the main mechanism responsible for the formation of irregular isolated spots during the combustion in terms of turbulence generation. The interaction of turbulent flow with blowing mass flus causes to breakup turbulent coherent structures and to form the small scale isolated eddies near the fuel surface. This mechanism attributes to the formation of irregular isolated sopt on the fuel surface.