The nonlinear characteristics of electric butterfly valve are very prominent
The nonlinearity of the electric butterfly valve is very obvious. Without considering the nonlinearity of the electric butterfly valve data, expand the radius of the two throttling orifices to the same diameter as the vertical diameter of the additional air chamber. That is, eliminate the influence of the throttling orifices. Use the method of phase plan to study the nonlinearity of the electric butterfly valve. Assume that the initial displacement value is always at the flat street position, and the initial velocity value is from 0 to 0.12 π m/s, Draw a family of phase trajectory curves of the vibration equation according to the drawing method of the phase plane diagram, as shown in Figure 2. It can be seen that the initial value xo=0. Vo=0) is the singular point of the phase trajectory. At this time, it is the static equilibrium point of the vibration system: the phase trajectory corresponding to each group of initial values is a locking ring. Therefore, the free vibration of the butterfly valve is periodic: with the increase of the initial speed, The phase trajectory loop gradually changes from the approximate i four shape to the egg shape. It indicates that the vibration of the system is close to linear vibration when the initial kinetic energy of the system is small. The nonlinearity of the vibration is very significant when the initial kinetic energy is large