The Study On Lift Force And Dynamic Response Analysis Of Cylinder

For a cylinder in water, the vortices will shed alternating behind the cylinder when water flows. It can make the cylinder vibrate and cause the lift force in the transverse direction and the drag force in the streamwise direction. This paper mainly focuses on the lift force which induces vibration of the cylinder. The lift force is analyzed in time domain and frequency domain. Then use it to solve the vibration differential equation and get the vibration displacement of the cylinder.In time domain, the maximal vibration displacement is calculated on the basis of experimental data via the semi-experiential and semi-theoretical method in this paper. This method is contrasted with other methods and it shows that this method has better precision.In frequency domain, spectrum expression of lift force is put forward via fitting the experimental data with probability density function of Weibull distribution. The maximal vibration displacement of the oscillating cylinder can be deduced by using the spectrum expression of lift force. The analysis shows that the calculated data nearly fit with the experimental data.