Effect of time dependent normal transpiration on the problem of unsteady viscous flow and heat transfer in the vicinity of an axisymmetric stagnation point of an infinite circular cylinder moving simultaneously with time-depended angular and axial velocities and with time-dependent wall temperature or wall heat flux are investigated. The impinging free stream is steady with a strain rate . A re...

The six-degree equations of flight in their classic form do not provide a proper physical perception due to a number of interferences. Nor do they render visible the important role of attack angles. In this study, attempts have been made to develop a complete set of 3D acceleration equations from the equations of normal and tangential acceleration αN=vωv, αt=v ̇. For this purpose, a coordinate s...

The integration of the rotation from a given angular velocity is often required in practice. The present paper explores how the choice of the parametrization of rotation, when employed in conjuction with different numerical time-integration schemes, effects the accuracy and the computational efficiency. Three rotation parametrizations – the rotational vector, the Argyris tangential vector and t...

introduction: knee joint has the highest percentage of injuries among lower extremity joints especially in athletes and people with high activity levels. therefore, analyzing of knee movements has an important area of research in the bioengineering and rehabilitation fields. sharif human movement instrumentation system (sharif-hmis) is a new inertial sensor designed for movement analysis. the p...

The angular momentum, angular velocity, Kelvin circulation, and vortex velocity vectors of a quantum Riemann rotor are proven to be either (1) aligned with a principal axis or (2) lie in a principal plane of the inertia ellipsoid. In the second case, the ratios of the components of the Kelvin circulation to the corresponding components of the angular momentum, and the ratios of the components o...

In this study, dynamic behavior of safety mechanism of a mechanical controller is investigated using 3D-FE simulation. This paper is concentrated on controller of a high acceleration projectile. The controller is located in the top of the projectile. Safety mechanism is divided to deformable and rigid parts. Deformable and rigid parts are simulated in Abaqus and Adams commercial soft wares; res...

The problem of concentric pervious spheres carrying a fluid source at their centre and rotating slowly with different uniform angular velocities Ω1, Ω2 about a diameter has been studied. The analysis reveals that only azimuthal component of velocity exists, and the couple, rate of dissipated energy is found analytically in the present situation. The expression of couple on inner sphere rotating...

The six-degree equations of flight in their classic form do not provide a proper physical perception due to a number of interferences. Nor do they render visible the important role of attack angles. In this study, attempts have been made to develop a complete set of 3D acceleration equations from the equations of normal and tangential acceleration αN=vωv, αt=v ̇. For this purpose, a coordinate s...