壓電式鼓風器設計與應用

Design of A Piezoelectric Micro Blower and Its Application

丁瑞諾(PANGESTU RENO)

指導教授 ： 丁鏞

中原大學/工學院/機械工程學系/碩士(2022年)

https://doi.org/10.6840/cycu202201270

摘要

摘要

本文是設計壓電微型鼓風器，使氣流垂直於壓電致動器的振動方向，可應用於智能手機設備之散熱。此微型鼓風器具雙腔各裝置一件壓電致動器(PZT-5H)。微型鼓風器性能的測量係使用有限元方法的分析模擬以及實驗測試驗證。壓電致動器之共振頻率之模擬值與實驗值分別為25.1kHz與23.2kHz。當施加20伏特電壓時，微型鼓風器可產生模擬值與實驗值分別為21.4 µm 以及 20.5 µm 振動位移。另利用 Navier-Stroke 定律估算輸出排氣流速。當各腔體之壓電致動器以180°的相位差輸入驅動電壓訊號會得到最大之氣流輸出，可產生模擬值與實驗值分別為1.23 ml/sec以及1.05 ml/sec。散熱實驗是以手機內之IC熱源，將散熱片置於IC熱源上方，利用排風之對流效應再經由散熱片以熱傳導方式散熱。實施案例驗證此鼓風機可以將功率IC 的熱量經過350秒從50°C的温度降低至智能手機的安全温度限制43°C以下。輸出排風量與散熱降温的分析與實驗結果结果相當吻合。

關鍵詞：壓電致動器、微型鼓風機、散熱。

關鍵字

壓電致動器 ； 微型鼓風機 ； 散熱

並列摘要

ABSTRACT
A dual-chamber piezoelectric micro-blower is designed to have airflow perpendicular to the vibration direction of the piezoelectric actuator for heat dissipation application in the smartphone device. This micro-blower is designed to have two diaphragms with a piezoelectric actuator (PZT-5H). Design and analysis via both analytical simulations using the finite element method are carried out for pursuing higher flowrate. Measurement of the performance of the micro-blower was conducted in experiment. The piezoelectric actuator works optimally at an ultrasonic frequency of 25.1 kHz based on the simulation and 23.2 kHz based on experiment. When 20 volts is applied, the piezoelectric produces a displacement of 21.4 µm in simulation and 20.5 µm in experiment. The laminar Navier-Stroke law is used for the estimation of airflow rate. The air pumping process works optimally when the two diaphragms vibrate with a phase angle difference of 180°. The resulting flow rate reaches 1.23 ml/s in simulation and 1.05 ml/s in experiment. The mobile power IC is a heat source, and the heatsink is attached to the top of the mobile power IC, so heat will be transferred by conduction. Then the heat from the heatsink will be dissipated by forced convection by a micro-blower. In examining the function of micro-blower, for example, the blower can dissipate the heat of power IC from a temperature from 50°C to below safe temperature limit of smartphone (43°C) for 350 second (5 minutes). The analytical and experimental results of flowrate and temperature reduction rate are in good agreement.
Keywords: Piezoelectric actuator, Micro-blower, Heat dissipation

並列關鍵字

Piezoelectric actuator ； Micro-blower ； Heat dissipation

參考文獻

BIBLIOGRAPHY

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