پديد آورنده :
نوربخش نيا، نسيبه
عنوان :
بررسي عددي و تجربي شكست پره هاي توربين گاز نيروگاه برق هسا
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
طراحي كاربردي
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده مكانيك
صفحه شمار :
[ده] ، 115،[II] ص: مصور، جدول، نمودار،تصوير﴿بخشي رنگي﴾
يادداشت :
ص.ع.:به فارسي و انگليسي
استاد راهنما :
سعيد ضيايي راد
استاد مشاور :
احمد كرمانپور
توصيفگر ها :
تيتانيوم , موسخليشويلي , تنش و سترگارد , نرم افزار ANSYS , آيروديناميك
تاريخ نمايه سازي :
27/1/87
چكيده فارسي :
به فارسي و انگليسي:قابل رويت در نسخه ديجيتال
چكيده انگليسي :
ABSTRACT This thesis concentrates on the frequently failures occurred in the high pressure compressorblades of the HESA Power Plant in Isfahan These blades belong to the 9th stage of the compressorand their material is titanium alloy Ti 6Al 4V In addition all reported failures are related to the rootpart of the blades Finite element method and software ANSYS was applied for the force analysis ofthe blades These simulations were carried out at both 2D and 3D dimensions under contact stresses which have the basic role on the failures centrifugal and aerodynamic forces The results showed ahigh stress gradient and Von Misses stress concentration on the edge of contact and it can beconcluded that this area is prepare for the crack initiation For investigating the stress condition of theblade and its root after initiation of cracks another simulation was carried out In this analysis different initial cracks were created on the geometry of the blade root by using a code which waswrote in ANSYS software It was shown that in all cracked root there is a high gradient and VonMisses stress concentration along the crack front which is higher than the fretting fatigue thresholdstress of Ti 6Al 4V It can prove that created cracks in this area can propagate by the mechanism offretting fatigue The stress intensity factors of the cracked roots were also evaluated along the crackfront It was shown that although all fracture modes are interfered in the blades failures the mode I isvery strong and has the chief part on the fractures In addition different metallurgical tests were carried out on the broken blade sections By thesetests the Fretting Fatigue was introduced as mechanism of crack initiation and the crack initiationpoints were also detected which exactly were the same point by the maximum stress concentration onthe edge of contact of the blade Thus the results of metallurgical tests can prove those ones obtainedby the numerical simulations
استاد راهنما :
سعيد ضيايي راد
استاد مشاور :
احمد كرمانپور
