Research and Development of Dynamic Balancing System with Astigmatic Pick-up Head for Miniature High-speed Turbine Cartridge

碩士 === 國立臺灣大學 === 機械工程學研究所 === 101 === The aim of this thesis is to develop a dynamic balancing system for the miniature high-speed turbine cartridge. The capability of this system is to decrease dynamic unbalance of the rotor of turbine cartridge, and to improve the dynamic balance quality for the...

Full description

Bibliographic Details
Main Authors: Si-Hui Yang, 楊思慧
Other Authors: Kuang-Yuh Huang
Format: Others
Language:zh-TW
Published: 2013
Online Access:http://ndltd.ncl.edu.tw/handle/71641974432402106314
Description
Summary:碩士 === 國立臺灣大學 === 機械工程學研究所 === 101 === The aim of this thesis is to develop a dynamic balancing system for the miniature high-speed turbine cartridge. The capability of this system is to decrease dynamic unbalance of the rotor of turbine cartridge, and to improve the dynamic balance quality for the high-speed operation range from 250~350 krpm. Although the turbine cartridge is precisely manufactured and assembled, the dynamic unbalanced vibration still induced because of high-speed operation. The dynamic unbalanced vibration would cause rotational run out, bearing wear, and noise. For measuring the dynamic unbalanced vibration, two pairs of length-adjustable parallel spring guides are used to support the rotating cartridge in order to transform the unbalance forces into the spring deformations. The unbalance vibrations can effectively stimulate the spring deformations through the length-adjustable spring to modulate their natural frequencies close to the rotational speed of turbine cartridge. The spring deformations are measured by two astigmatic pickup heads, which have been verified to be able to detect very tiny high-frequent deformation without any contact loading. And the angular positions of the rotor unbalances are simultaneously detected by two perpendicular arranged hall sensors. By using the influence coefficient method, the rotor unbalances can be derived from the detected spring deformations and their corresponding angular position. For removing tiny unbalances, the pulsed solid-state laser is applied to create precision ablation mass on the turbine vane. The measured ablation rate is about 14 ug for 1-sec operation time by using the 20 W solid-state laser with the pulse frequency of 60 kHz.   The experimental balancing testing shows that the astigmatic pickup heads can detect very tiny unbalanced vibration in a range from 14.6 nm to 39.1 nm, which corresponds to the unbalance mass from 38 μg to 23 μg on the turbine vane. Through the dynamic balancing operation, the rotating quality of high-speed cartridge can be 15.7 % ~ 33.9% improved. The developed dynamic balancing system is experimentally verified that its balance quality can achieve the ISO G2.5-level.