The main objective of this work is to use the CFD （Computational Fluid Dynamics） technique to study the effects of pitch ratio on the controllable pitch propeller＇s thrust characteristic. The propeller analyzed is ...The main objective of this work is to use the CFD （Computational Fluid Dynamics） technique to study the effects of pitch ratio on the controllable pitch propeller＇s thrust characteristic. The propeller analyzed is at the following design condition： diameter of 3.65 m, speed of 200 rpm, blade number of 4, average pitch of 2.459 m, pitch ratio at 0.7 of 0.6737. The first stage involves the mesh generation and refinement on domain of the designed propeller. The second stage deals with the identification of initial and boundary conditions of the mesh-equipped module. In the final stage, various results are calculated and analyzed for pitch ratio affecting on the propeller＇s thrust characteristic. The achieved results are the basis design and improving efficiency of the controllable pitch propeller.展开更多
The current research aims to simulate the flight trajectory of the North Korean submarine–launched ballistic missile(SLBM)and analyze its flight characteristics based on its range control method.Recently,North Korea ...The current research aims to simulate the flight trajectory of the North Korean submarine–launched ballistic missile(SLBM)and analyze its flight characteristics based on its range control method.Recently,North Korea has completed the test flight of SLBM and it has become a significant threat to international security.North Korea obtained SLBM technologies from Russia while disbanding decommissioned Russian submarines,and it is suspected that North Korea will continue to experiment in related fields along with its continued attempts to miniaturize nuclear weapons.If North Korea completes the development of SLBM and deploys the missiles,it means the completion of the three asymmetric warfare elements(nuclear weapon,ballistic missile,and submarine)and they will be the most significant threats to northeast Asia.Therefore,it is imperative to scientifically analyze SLBM to adeptly respond to such threat.One characteristic of SLBM is capability of attacking its target in a variety of ways based on its range control method.Based on this fact,the current research derives the flight equation of North Korean SLBM and simulates its flight trajectory based on various range control methods.The flight trajectories that we derive can be used to establish an effective anti-ballistic missile defense system in northeast Asia.展开更多
文摘The main objective of this work is to use the CFD （Computational Fluid Dynamics） technique to study the effects of pitch ratio on the controllable pitch propeller＇s thrust characteristic. The propeller analyzed is at the following design condition： diameter of 3.65 m, speed of 200 rpm, blade number of 4, average pitch of 2.459 m, pitch ratio at 0.7 of 0.6737. The first stage involves the mesh generation and refinement on domain of the designed propeller. The second stage deals with the identification of initial and boundary conditions of the mesh-equipped module. In the final stage, various results are calculated and analyzed for pitch ratio affecting on the propeller＇s thrust characteristic. The achieved results are the basis design and improving efficiency of the controllable pitch propeller.
文摘The current research aims to simulate the flight trajectory of the North Korean submarine–launched ballistic missile(SLBM)and analyze its flight characteristics based on its range control method.Recently,North Korea has completed the test flight of SLBM and it has become a significant threat to international security.North Korea obtained SLBM technologies from Russia while disbanding decommissioned Russian submarines,and it is suspected that North Korea will continue to experiment in related fields along with its continued attempts to miniaturize nuclear weapons.If North Korea completes the development of SLBM and deploys the missiles,it means the completion of the three asymmetric warfare elements(nuclear weapon,ballistic missile,and submarine)and they will be the most significant threats to northeast Asia.Therefore,it is imperative to scientifically analyze SLBM to adeptly respond to such threat.One characteristic of SLBM is capability of attacking its target in a variety of ways based on its range control method.Based on this fact,the current research derives the flight equation of North Korean SLBM and simulates its flight trajectory based on various range control methods.The flight trajectories that we derive can be used to establish an effective anti-ballistic missile defense system in northeast Asia.
