外文翻譯---旋轉(zhuǎn)機械葉片振動時軸的瞬時角速度

1、出處：Gubran A A, Sinha J K. Shaft instantaneous angular speed for blade vibration in rotating machine[J]. Mechanical Systems and Signal Processing, 2014, 44(1): 47-59.中文 6044 字附錄 英文資料及翻譯Shaft instantaneous angular speed fo

2、r blade vibration in rotating machine Ahmed A.Gubran,JyotiK.SinhaSchool of Mechanical, Aerospace and Civil Engineering (MACE), The University of Manchester, Sackville Street, Manchester M13 9PL, UK article infoArticle hi

3、story:Received 29June2012Received in revised form19 December2012Accepted 3February2013Keywords:Instantaneous angular speed(IAS)Blade vibrationBlade health monitoring(BHM)Blade faultsShaft torsional vibrationOrder trackin

4、gAbstractReliable blade health monitoring(BHM) in rotating machines like steam turbines and gas turbines,is a topic of research since decades to reduce machine down time,maintenance costs and to maintain the overall safe

5、ty.Transverse blade vibration is often transmitted to the shaft as torsional vibration.The shaft instantaneous angular speed(IAS) is nothing but the representing the shaft torsional vibration.Hence the shaft IAS has been

6、 extracted from the measured encoder data during machine run-up to understand the blade Vibration and to explore the possibility of reliable assessment of blade health.A number of experiments on an experimental rig with

7、a bladed disk were conducted with healthy but mistuned blades and with different faults simulation in the blades.The measured Shaft torsional vibration shows a distinct difference between the healthy and the faulty blade

8、 conditions.Hence,the observations are useful for the BHM in future.The paper Presents the experimental setup,simulation of blade faults,experiments conducted, Observations and results.1. Introduction Rotating blades are

9、 considered as the most common cause of failures in rotating machinery. The extraction process from the encoder measurement, rig details, blade faults simulations, experiments conducted and the observations on the blade

10、dynamics which may possibly lead to the BHM in future. 2.Instantaneous angular speed (IAS) measurement An encoder that measures 360 pulses for every complete rotation of a shaft has been used for the present experiment.

11、To aid the understanding of the IAS signal extraction from the measured encoder pulse train, a simplified measurement scheme of the encoder and the pulse train is shown in Fig. 1. The sensor simply measures the gap betwe

12、en each tooth on the gear during its rotation which results in the pulse train of the measured gap voltage with time as shown in Fig. 1. The extraction of instantaneous angular speed (IAS) signal using the pulse train in

13、 Fig. 1 is discussed in the following steps .(i) Each square pulse represents a tooth in the gear of the encoder, hence the difference of times ,t2-t1,t3-t2,...tn+1-tn, etc.represents the time interval required to cross

14、the 1st, 2nd,..., nth tooth respectively which is written as (1) n n n t t t ? ? ? ?1Fig. 1. Pulse train created from shaft encoder It is also assumed that the time interval for nth tooth is measured at the time, Tn