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Chaotic dynamics of spin-orbit motion of a triaxial gyrostat satellite under the gravity gradient perturbations is considered. The Hamiltonian approach is used for modeling of the coupled spin-orbit equations of motion. The complex Hamiltonian of the system is reduced via the extended Deprit canonical transformation. This reduction yields to the derivation of the perturbation form of the Hamiltonian which can be used in the Ricci curvature criterion based on the Riemannian manifold geometry for the analysis of chaos. The results obtained from Ricci method as well as the values from the Lyapunov exponent demonstrate the presence of a strange attractor and chaos phenomenon in the perturbed system. The simulation results based on the numerical methods such as Poincare' section, trajectories of phase portrait, and time series responses confirm the heteroclinic bifurcation and chaos in the system.

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One way to control the position of the missile is controling thrust vector that is moves with help of thrust due to exit of gas. All thrust vector control (TVC) methods are independent of aerodynamic forces of atmosphere and until the engine has thrust, maintain their performance. Secondary injection systems are one of the four major TVC methods. In this study,at first identify the components and design entire conceptualdesigning of system and the preliminary design of manifold of a type of thrust vector control system using a liquid injection thrust vector control (LITVC)has been proceed. Then the layouts of components on some components such as injectors and reservoirs, as well as detailed design of the system are discussed. Then the numerical simulation of flow and the designing and studying the sprayers in LITVC systems will be discussed. Also numerical designing and simulation in two parts: injection system and the injector spray effects into the main flow are analyzed and the results are presented and validated. The achievement of this study can be used as a model for designing and analyzing of various kinds of TVC systems with lateral fluid method on a variety of missiles with different launchers.

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The task of the intake air manifold of gasoline engines is to transfer air, crankcase vapors, blow-by flow, fuel tank vapors, and fuel injected into the passages of the engine cylinder head. This part must be designed in such a way that it can supply the air needed by the car engine in different conditions of its operation with the lowest pressure drop and speed and distribute it equally between the engine cylinders in terms of flow rate and air-fuel ratio. Also, the mixing of oil vapors, blow-by flow and gasoline vapors of the engine is done in it and distributed equally between different cylinders. To achieve this goal, the air manifold needs to be designed in the most optimal way. In this research, the EC5 engine has been examined. The intended engine is designed and simulated in GT-SUITE software and the desired information for this modeling is practically extracted. The model designed in the software has been validated using experimental results. Then, using the desired model, the resonance volume in the air manifold has been investigated. Two engine models have been designed and compared using resonant volume and without using resonant volume in the inlet air manifold. The results of this comparison show that the engine with resonance volume had an increase in power of about 10 kW at engine speed of 6000 rpm