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
RECENTLY, we have successfully developed new nanocrystalline Fe<sub>72</sub>Cu<sub>1</sub> Nb<sub>2</sub>V<sub>2</sub>Si<sub><</sub>sub>14</sub>B...RECENTLY, we have successfully developed new nanocrystalline Fe<sub>72</sub>Cu<sub>1</sub> Nb<sub>2</sub>V<sub>2</sub>Si<sub><</sub>sub>14</sub>B<sub>9</sub> and Fe<sub>72</sub>-Cu<sub>1</sub>Nb<sub>1</sub>Mo<sub>1</sub>V<sub>2</sub>Si<sub>14</sub>B<sub>9</sub> alloys. Their cost has been reduced and their amorphous ribbons havemuch better ductillty as compared with the early-developed and typical nanocrystalline Fe<sub>73.5</sub>-Cu<sub>1</sub>Nb<sub>3</sub>Si<sub>13.5</sub>B<sub>9</sub> and Fe<sub>73.1</sub> Cu<sub>1.2</sub>Nb<sub>3.2</sub>Si<sub>12.5</sub>B<sub>10</sub> alloys. The new alloys still show superiorsynthetical magnetic properties and have practically been applied to several important fields. Inthis note, we report magnetic properties for the new alloys, analysis results of core losses andseveral application examples.展开更多
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.
文摘RECENTLY, we have successfully developed new nanocrystalline Fe<sub>72</sub>Cu<sub>1</sub> Nb<sub>2</sub>V<sub>2</sub>Si<sub><</sub>sub>14</sub>B<sub>9</sub> and Fe<sub>72</sub>-Cu<sub>1</sub>Nb<sub>1</sub>Mo<sub>1</sub>V<sub>2</sub>Si<sub>14</sub>B<sub>9</sub> alloys. Their cost has been reduced and their amorphous ribbons havemuch better ductillty as compared with the early-developed and typical nanocrystalline Fe<sub>73.5</sub>-Cu<sub>1</sub>Nb<sub>3</sub>Si<sub>13.5</sub>B<sub>9</sub> and Fe<sub>73.1</sub> Cu<sub>1.2</sub>Nb<sub>3.2</sub>Si<sub>12.5</sub>B<sub>10</sub> alloys. The new alloys still show superiorsynthetical magnetic properties and have practically been applied to several important fields. Inthis note, we report magnetic properties for the new alloys, analysis results of core losses andseveral application examples.