Upper stage solid rocket motors （SRMS） for launch vehicles require a highly efficient propulsion system. Grain design proves to be vital in terms of minimizing inert mass by adopting a high volumetric efficiency wit...Upper stage solid rocket motors （SRMS） for launch vehicles require a highly efficient propulsion system. Grain design proves to be vital in terms of minimizing inert mass by adopting a high volumetric efficiency with minimum possible sliver. In this arti- cle, a methodology has been presented for designing three-dimensional （3D） grain configuration of radial slot for upper stage solid rocket motors. The design process involves parametric modeling of the geometry in computer aided design （CAD） software through dynamic variables that define the complex configuration. Grain bum back is achieved by making new surfaces at each web increment and calculating geometrical properties at each step. Geometrical calculations are based on volume and change-in-volume calculations. Equilibrium pressure method is used to calculate the internal ballistics. Genetic algorithm （GA） has been used as the optimizer because of its robustness and efficient capacity to explore the design space for global optimum solution and eliminate the requirement of an initial guess. Average thrust maximization under design constraints is the objective function.展开更多
In this paper,a novel pyrogenic pulser was designed both analytically and numerically and was evaluated with empirical tests.The motivation of this study was the need for active control of the aero acoustic pressure o...In this paper,a novel pyrogenic pulser was designed both analytically and numerically and was evaluated with empirical tests.The motivation of this study was the need for active control of the aero acoustic pressure oscillations by injecting the secondary flow into the solid rocket motor.First,in brief,pyrotechnic and pyrogenic pulsers were introduced,and then analytical governing equations were presented in three transient,sinusoidal and Hercules methods.In order to understand the internal pressure of the pulsar and its plume length,the injection flow field was evaluated using the ANSYS-Fluent software with both k-ωSST and k-εRealizable models both at ambient and motor pressure.After that,the design and manufacturing of the pulser hardware and the test process were described.Finally,analytical,numerical and experimental results were discussed.The results show that there is a good correlation between the transient analysis in theory and the numerical solution by the k-ωSST model and the empirical test data.In addition,pyrogenic pulsers design depends on various parameters of motor and pulser charge performance prediction.The quality of pulser charge bonding to its insulator and erosion of its throat path due to injection have an important role to obtain a desirable pulser mass flow rate and plume length.展开更多
文摘Upper stage solid rocket motors （SRMS） for launch vehicles require a highly efficient propulsion system. Grain design proves to be vital in terms of minimizing inert mass by adopting a high volumetric efficiency with minimum possible sliver. In this arti- cle, a methodology has been presented for designing three-dimensional （3D） grain configuration of radial slot for upper stage solid rocket motors. The design process involves parametric modeling of the geometry in computer aided design （CAD） software through dynamic variables that define the complex configuration. Grain bum back is achieved by making new surfaces at each web increment and calculating geometrical properties at each step. Geometrical calculations are based on volume and change-in-volume calculations. Equilibrium pressure method is used to calculate the internal ballistics. Genetic algorithm （GA） has been used as the optimizer because of its robustness and efficient capacity to explore the design space for global optimum solution and eliminate the requirement of an initial guess. Average thrust maximization under design constraints is the objective function.
文摘In this paper,a novel pyrogenic pulser was designed both analytically and numerically and was evaluated with empirical tests.The motivation of this study was the need for active control of the aero acoustic pressure oscillations by injecting the secondary flow into the solid rocket motor.First,in brief,pyrotechnic and pyrogenic pulsers were introduced,and then analytical governing equations were presented in three transient,sinusoidal and Hercules methods.In order to understand the internal pressure of the pulsar and its plume length,the injection flow field was evaluated using the ANSYS-Fluent software with both k-ωSST and k-εRealizable models both at ambient and motor pressure.After that,the design and manufacturing of the pulser hardware and the test process were described.Finally,analytical,numerical and experimental results were discussed.The results show that there is a good correlation between the transient analysis in theory and the numerical solution by the k-ωSST model and the empirical test data.In addition,pyrogenic pulsers design depends on various parameters of motor and pulser charge performance prediction.The quality of pulser charge bonding to its insulator and erosion of its throat path due to injection have an important role to obtain a desirable pulser mass flow rate and plume length.
