Dynamic Behavior of a Micro-Beam Subjected to Voltage and Fluid Flow as a Micro Vortex Generator

The present work investigated the nonlinear vibration of a cantilever cylindrical microbeam subjected to voltage and fluid flow as a micro vortex generator. As the microbeam is subjected to the fluid with a given velocity, in addition to the load due to fluid added mass, the lift and drag forces as the two basic flow-induced factors affecting the dynamics of the micro-beam were modeled using Van der pol equation. The Euler-Bernoulli beam theory was used to model the cross fluid motion of beam under nonlinear electrostatic force as a result of the applied voltage. The Galerkin method was used to convert the partial differential equation to regular differential equations as well as to solve the coupled nonlinear equations governing the micro-beam motion and the wake oscillation to evaluate the response of the coupled structure to a combined applied voltage and fluid flow. The effect of fluid flow on the Reynolds number and fluid vortex frequency as two main parameters in the creation of the Lock-in phenomenon was studied. In addition to the effect of different fluid velocities, the response of the microbeam to different input voltages in the presence of fluid flow was investigated and it was shown that for a given flowing fluid, the applied voltage can be used to control the lock-in regime. Review History: Received: 2018/06/02