【正文】 助下，以及自己的辛勤勞動(dòng)下，終于完成了這次意義非凡的畢業(yè)設(shè)計(jì)工作，為大學(xué)的學(xué)習(xí)生涯畫(huà)上了一個(gè)圓滿的句號(hào)。 在這里要感謝我的畢業(yè)設(shè)計(jì)指導(dǎo)老師李朝峰老師，大到設(shè)計(jì)課題的選擇和畢業(yè)設(shè)計(jì)的整體流程，小到章節(jié)內(nèi)容的選定和論文里的每一個(gè)細(xì)節(jié)，無(wú)不得到了老師認(rèn)真熱心的指導(dǎo)與幫助，在此表示衷心的感謝和誠(chéng)摯的敬意！ 畢業(yè)設(shè)計(jì)雖然結(jié)束了，大學(xué)四年的學(xué)習(xí)生活也即將結(jié)束，但這只是人生的一個(gè)新征程的開(kāi)始。因此，在以后的工作和學(xué)習(xí)生活中，我將繼續(xù)努力研究專業(yè)知識(shí)，并且將大學(xué)知識(shí)所學(xué)應(yīng)用與實(shí)際工作相結(jié)合，將自己的知識(shí)服務(wù)于社會(huì)，做到學(xué)以致用，創(chuàng)造自己的價(jià)值。 東北大學(xué)畢業(yè)設(shè)計(jì) 附錄附錄 英文資料及翻譯Shaft instantaneous angular speed for blade vibration in rotating machine Ahmed ,School of Mechanical, Aerospace and Civil Engineering (MACE), The University of Manchester, Sackville Street, Manchester M13 9PL, UK article infoArticle history:Received 29June2012Received in revised form19 December2012Accepted 3February2013Keywords:Instantaneous angular speed(IAS)Blade vibrationBlade health monitoring(BHM)Blade faultsShaft torsional vibrationOrder trackingAbstractReliable 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 blade vibration is often transmitted to the shaft as torsional shaft instantaneous angular speed(IAS) is nothing but the representing the shaft torsional the shaft IAS has been extracted from the measured encoder data during machine runup to understand the blade Vibration and to explore the possibility of reliable assessment of blade number of experiments on an experimental rig with a bladed disk were conducted with healthy but mistuned blades and with different faults simulation in the measured Shaft torsional vibration shows a distinct difference between the healthy and the faulty blade ,the observations are useful for the BHM in paper Presents the experimental setup,simulation of blade faults,experiments conducted, Observations and results.1. Introduction Rotating blades are considered as the most mon cause of failures in rotating machinery. The blade failure modes normally occur as a result of cracking, high cycle stresses, blade rubbing, blade root looseness, degradation from erosion and corrosion. Therefore, early fault detection is important in reducing blade related failures and hence there is a need of a reliable and simple blade health monitoring (BHM) technique. Sinha et al. [1] recently analyse the insitu measured vibration data at the bearing pedestals during the steady state and the transient operations in the steam turbines to understand the machine dynamics, and to identify the root cause of the failure of the last stage blades in the low pressure turbines. AlBedoor [2] gave the review of different research methods that has been attempted for blade vibration measurements till year 2002. Insitu casing vibration near the last stage of a low pressure (LP) turbine in a steam turbo generator (TG) set was observed to show the trace of blade resonance only during the fluctuation in the condenser pressure due to change in loads [3]. But such observation contains very limited information and may not be useful for diagnosis. Strain measurement on the blades during the machine operation is another option [4], this is where strain can be measured directly and hence the stress and possibly residual blade life can be estimated [5]. The blade tip time (BTT) has received attention in recent years and it can identify blades with high vibration [4,6]. However both the BTT and the strain measurement methods are intrusive and exorbitant methods. Hence there is a need for reliable and simple but robust method to meet the requirements of the BHM. The use of the encoder in rotating machines is seems to be a mon practice to measure the shaft speed. The shaft instantaneous angular speed (IAS) signal from the encoder raw signal based on timeintervals change between successive pulses is nothing but the representing the shaft torsional vibration. This method is generally nonintrusive and non exorbitant method and now the topic of research for different applications. A few of them include the identification of faulty bustion cylinder(s) in the diesel engines [7,8] using the crank shaft IAS signal and the IAS response of the shaft with fault(s) in rotating machine [9,10]. It has also been reported in the literature that transverse blade vibration is often reflected in the shaft torsional vibration. It was experimentally verified on small rigs, and the mistuning effect on the blade natural frequency was also observed [11,12]. Maynard and Trethewey [13] have also demonstrated the field application on the use of the torsional vibration for tracking crack in shaft and blades. Analytical simulations [14] and Huang and Ho [15] have also shown the potential of the shaft torsional vibration that could be used as the condition monitoring for turbine blades. However, Sinha et al. [16] could not identify the last stage blade resonance during normal operation of a steam turbine in a 220 MW Nuclear Power Plant in India. The transient operation of machine may be useful for such machines. Hence the shaft IAS has been extracted from the measured encoder data during the machine transient operation to understand the dynamics of the blades and to explore the possibility of reliable assessment of the blade health. A series of experiments were conducted on a test rig with an 8bladed disc for three different conditions: (1) healthy with mistuned effects, (2) blade root looseness and (3) blade(s) with crack. These conditions are often observed in practice for the rotating machines like steam turbines, gas turbines, etc. and hence the early and reliable detection of the faulty conditions (2) and (3) is important. The extracted IAS signal from the encoder raw data during the machine runup were then order tracked at the different engine order (EO) speeds so that the presence of the blade resonances, their higher harmonics and dynamics behaviour can be analysed. The measured shaft torsional vibration shows a d