in this paper the effects of non-linearity of suspension on dynamic behavior of a railway wheelset has been studied. this wheelset has four degrees of freedom that with two constraints it has reduced to two degrees of freedom. vermeulen-johnson theory has been used to calculate contact forces between wheel and rail. in this study the creep coefficients have considered constant. any linearizatio...

in this paper, nonlinear dynamic behaviours of carbon nanotube conveying fluidwith slip boundary conditions is studied using variation iteration method. the developed solutions are used to investigate the effects of various parameters on the nonlinear vibration of the nanotube. from the result, it is observed that increase in the slip parameter leads to decrease in the frequency of vibration an...

magnesium alloys in liquid-phase condition form surface oxide films due to their high rate of oxidation. oxide films enter the melt as a result of surface turbulence, and remain inside the workpiece after solidification. the incoherent nature of their interface causes decreases in mechanical properties and reliability of castings. the effect of critical velocity and greater velocities of enteri...

In this paper, nonlinear dynamic behaviour of the carbon nanotube conveying fluid in slip boundary conditions is studied using the variation iteration method. The developed solutions are used to investigate the effects of various parameters on the nonlinear vibration of the nanotube. The results indicate that an increase in the slip parameter leads to a decrease in the frequency of vibration an...

abstract weirs are the most common structures for discharge measurement in engineering research. streamline curvature, non hydrostatic pressure distribution on weir and nappe adherence to the weir lead to differences between calculated and measured discharges. thus discharge coefficient, which is the ratio of real and theoretic discharges, is usually less than unity. in circular weirs the press...

suspension system is one of the most important factors in provision of ride comfort and dynamic stability in any vehicle. meanwhile the suspension systems of tracked vehicles, due to their continuous track, have particular specification in comparison with other vehicles. this specification causes tracked vehicles having an improved dynamic stability in off-road maneuvers compared to vehicles wi...

the high blood rate that often occurs in arteries may play a role in artery failure and tortuosity which leads to blackouts, transitory ischemic attacks and other diseases. however, vibration and instability analysis of carotid arteries are lacking. the objective of this study is to investigate the vibration and instability of the carotid arteries conveying blood under axial tension with surrou...