Active Vibration Control Analysis of Cantilever Pipe Conveying Fluid Using Smart Material

Abstract

In this paper, experimental and simulation studies in active vibration of smart cantilever pipe conveying fluid have been presented to investigate the open and closed loop time responses.

A program to simulate the active vibration reduction of stiffened pipe with piezoelectric sensors and actuators was written in the ANSYS workbench and  Parametric Design Language (APDL). This makes use of the finite element capability of ANSYS and incorporates an estimator based on optimal linear quadratic control (LQR) schemes to investigate the open and closed loop time responses. The procedures are tested by active control for free and forced vibrations of piezoelectric smart cantiliver pipe conveying fluid. Harmonic excitation is considered in the forced vibration.

Experiments have been done to verify with simulations. Smart pipe consists of aluminum pipe surface glued piezoelectric patches of MIDÉ QuickPack QP20W transducers. An experimental result is acquired by LabVIEW programs.

It is found the location of the piezoelectric actuator has in influence on the response of the cantilever pipe. The displacement increases when the actuators are moved closer to the clamped. This is due to the higher strain developed near the clamped .

The control performance  decrease with increasing  the flow velocity due to increased  coriolis force.The better performance of control occur at minimum velocity(Q=10L/min) and location1 of actuator, the maximum reduced the displacement response from +8mm to 1mm.

Keywords: Active vibration control, LQR, cantilever pipe, smart structure, Smart material, piezoelectric.