The Effects of geometric design parameters on the flow behavior of a dual pulse solid rocket motor during secondary firing

Download
2012
Ertuğrul, Suat Erdem
The ability of a propulsion system is very crucial for the capability of a missile or a rocket system. Unlike liquid propellant rocket motors, the only control mechanism of the thrust value is the propellant geometry in solid propellant rocket motors. When the operation of solid propellant rocket motor has started, it cannot be stopped anymore. For this main reason the advance of dual pulse motor technology has started. The aim of this study is to investigate the geometrical effects of design parameters on the flow behavior of a dual pulse solid propellant rocket motor by using commercial Computational Fluid Dynamics (CFD) methods. For the CFD analysis, a generic dual pulse rocket motor model is constituted. Within this model, initially four different geometry alternatives of Pulse Separation Device (PSD) are analyzed. To begin PSD analyses, mesh sensitivity analyses are performed on one PSD geometry alternative. By defined grid size, the analyses of PSD geometry alternatives are performed. Computed results were compared in terms of flow behavior (flow streamlines, velocity distribution, turbulent kinetic energy… etc.) with each other. With the selected PSD geometry alternative the effects of L/D ratio (Length/Diameter ratio) of first pulse chamber, Achamb/APSD ratio (Chamber area/PSD opening area) and APSD/Ath ratio (PSD opening area/Throat area) on the flow behavior is investigated. Flow analyses are performed by simulating the unsteady flow of second pulse operation. With the performed analyses, it is aimed to identify generic geometric definitions for a dual pulse rocket motor.

Suggestions

Determining service life and ageing characteristics of composite solid propellants by their chemical properties
Kösa, Yasemin; Üner, Deniz; Kesik Mancar, Melis; Department of Chemical Engineering (2022-2)
Solid composite propellants are widely used in rocket systems due to their extended manageability and practicality. Service life determination issue of these energetic materials is an extremely important subject as performance and operation safety of rockets may greatly be affected by ageing of propellant. In the literature, service life determination of composite propellants is commonly based on mechanical properties such as stress and strain parameters. In this study, direct monitoring of chemical alterat...
Experimental and numerical investigation of a jet vane of thrust vector control system
Söğütcü, Burak.; Perçin, Mustafa; Department of Aerospace Engineering (2019)
Thrust vectoring is generally used in tactical missile systems when attitude control with conventional control systems is inadequate. One of the most widely used thrust vectoring method is to employ jet vanes in the divergent section of the rocket motor nozzle to have the desired thrust vectoring. In the present study, the flow over the jet vane of a thrust vector control system is investigated using both numerical and experimental techniques. Three dimensional, unsteady and viscous flow over the jet vane i...
Investigating the dominant factors regarding ignition transient in the design procedure of the nozzle of a pyrogen igniter
Yeşilyurt, Yavuz; Güvenç Yazıcıoğlu, Almıla; Department of Mechanical Engineering (2019)
In a standard solid rocket motor (SRM) system, the propellant of the SRM is generally ignited by a pyrotechnic device (which is much smaller in size compared to SRM itself). However, grand systems like solid propellant Space Propulsion Systems need more mass flow rate in a very short time duration to be ignited, which is not easy task for a pyrotechnic igniter. The solution for this issue is utilizing pyrogen igniter in the SRM system, which is both a small-scale SRM and an igniter. Here ignition transient ...
Three-dimensional retarding walls and flow in their vicinity
Toker, Kemal Atılgan; Aksel, Mehmet Haluk; Department of Mechanical Engineering (2004)
The performance prediction of solid propellant rocket motor depends on the calculation of internal aerodynamics of the motor through its operational life. In order to obtain the control volume, in which the solutions will be carried out, a process called أgrain burnback calculationؤ is required. During the operation of the motor, as the interface between the solid and gas phases moves towards the solid propellant in a direction normal to the surface, the combustion products are generated and added into the ...
Service life assessment of solid rocket propellants considering random thermal and vibratory loads
Yılmaz, Okan; Özgen, Gökhan Osman; Kuran, Bayındır; Department of Mechanical Engineering (2012)
In this study, a detailed service life assessment procedure for solid propellant rockets under random environmental temperature and transportation loads is introduced. During storage and deployment of rocket motors, uncontrolled thermal environments and random vibratory loads due to transportation induce random stresses and strains in the propellant which provoke mechanical damage. In addition, structural capability degrades due to environmental conditions and induced stresses and strains as well as materia...
Citation Formats
S. E. Ertuğrul, “The Effects of geometric design parameters on the flow behavior of a dual pulse solid rocket motor during secondary firing,” M.S. - Master of Science, Middle East Technical University, 2012.