Constrained-layer Damping Applied to DCJ Vibration Isolation Design

G M Luo

doi:10.12691/jmdv-5-1-3

Abstract

A dual piezoelectric cooling jet (DCJ) is an innovative cooling device that uses piezoelectric materials to generate high-speed vibrations, thereby causing changes in the flow field to achieve heat exchange. Despite its high cooling efficiency, a DCJ transfers vibrations through its supporting base to its peripheral devices. To attenuate vibrations from DCJs, this study employed constrained-layer damping (CLD)-a technique for suppressing vibrations-to develop a base for cooling devices and to propose a C-DCJ model. ANSYS simulation of the vibrations of a DCJ and the C-DCJ suggested that, under the same vibration conditions and with the same levels of cooling efficiency, the amplitude and acceleration of the base on the C-DCJ were 30%â50% lower than that on the DCJ. Thus, the proposed C-DCJ effectively isolated vibration transfer.

Highlights

As precision machinery becomes increasingly miniaturized, numerous cooling devices such as dual piezoelectric cooling jets (DCJs) have been developed to replace conventional fans in such machines
constrained-layer damping (CLD) was used to isolate the transfer of vibrations from the DCJ model to the base, and whether these vibrations could be perceived by humans was measured
The DCJ model used in this study had its thin metal sheets attached by viscoelastic gel to the base

Summary

Introduction

As precision machinery becomes increasingly miniaturized, numerous cooling devices such as dual piezoelectric cooling jets (DCJs) have been developed to replace conventional fans in such machines. A DCJ is a thin, highly efficient cooling device that uses piezoelectric materials to vibrate two thin metal sheets, thereby altering the flow of air to enable heat exchange. They are suitable to be employed in mobile phones and tablet computers. Developed by General Electric in 2012, a DCJ has heat transfer efficiency 10 times greater than is achieved by natural convection and is inaudible to humans during operation [1]. The following year, Jang and Lee [3] performed a numerical analysis of the airflow characteristics of DCJs, altering the electric current to cause cyclic variations in the devices and allow them to continually produce airflow, and performed a spectral analysis of the airflow

Results

Discussion

Conclusion