İTÜ-HTH Tork Tüp Tasarımı Ve Testleri
İTÜ-HTH Tork Tüp Tasarımı Ve Testleri
Dosyalar
Tarih
31.07.2012
Yazarlar
Kuzubaşoğlu, Muzaffer
Süreli Yayın başlığı
Süreli Yayın ISSN
Cilt Başlığı
Yayınevi
Fen Bilimleri Enstitüsü
Institute of Science and Technology
Institute of Science and Technology
Özet
Bu çalışmada İTÜ Hafif Ticari Helikopterinin tork tüpü yapılması amaçlanmıştır. Helikopterlerde bulunan ve daha önce İTÜ-ROTAM’da tasarımı ve testleri yapılmış tork tüpleri incelenmiştir. İTÜ-HTH’ı hakkında genel bilgiler verilmiştir. İTÜ-HTH, altı yolcu ,iki pilot kapasiteli tek motorlu helikopterdir. İTÜ-HTH’ın en önemli özellikleri güvenirliği, kullanım kolaylığı ,düşük ses seviyesi, maliyetidir.Yataksız hub sistemine ve kompozit palalara sahip olması, yüksek Anadolu platosunda yüksek irtifa görevlerini rahatlıkla yerine getirebilecek olması , düşük ana rotor dönüş devrinin sonucu olarak düşük uç hızına ve düşük ses seviyesine sahip olması İTU-HTH’ı rakiplerinden ayıran özelliklerdir. İTÜ-HTH havada asılı kalma, düşük hızda seyir uçuşu, uzun mesafe uçuşu gibi farklı görevleri yapabilmek için tasarlanmıştır. İTÜ-HTH ticari uygulamalar, kamu uygulamaları ve kişisel uygulamalar için kullanılabilir. İTÜ-HTH’ı oluşturan gövde, iniş takımı, uçuş kontrol sistemi ,itki sistemi, güç aktarma sistemi, yakıt sistemi, elektrik sistemi ve ana rotor sistemi hakkında bilgiler verilmiştir. İTÜ-HTH’ın farklı uçuş şartları altında performans analizleri yapılmıştır. Tasarım isterleri doğrultusunda, farklı uçuş şartları altında çalışabilecek tork tüp tasarımı yapılmıştır. Tork tüpünün sonlu elemanlar modeli oluşturulmuştur. Sonlu elemanlar modeline uygun sınır şartları ve kuvvetlerin uygulanması ile sonlu elemanlar analizleri tamamlanmıştır. Analiz sonucu oluşan gerilme değerleri incelenmiştir. Tork tüpünün üretimi için teknik resimleri hazırlanmıştır. Pala kesiti üzerine tork tüp montajı yapılmıştır. İTÜ-ROTAM’da bulunan yapı laboratuvarında MTS Test cihazı ve yardımcı ekipmanlar yardımıyla tork tüpünün yapısal testleri standart ve ekstrem uçuş şartları olmak üzere iki farklı durum için yapılmıştır. Yapısal testlerde, aerodinamik momentleri modellemek amacıyla çelik kiriş kullanılmıştır. Standart uçuş şartları etkisinde, tork tüpünün 75 uçuş saati (1500000 çevrim) süresince kırıma uğramaması için yorulma testi yapılmıştır. Merkezkaç testi standart uçuş şartları yorulma testleri sonrasında yapılmıştır. Tork tüpe merkezkaç kuvvetin iki ve üç katı kuvvet uygulanarak çekilmiştir. Standart uçuş şartları testlerinde elde edilen gerilme değerleri, emniyetli akma gerilmesi değerinden düşüktür. Ekstrem uçuş şartlar etkisinde tork tüpün statik ve yorulma testleri yapılmıştır. Ekstrem uçuş testlerinde elde edilen gerilme değerleri, emniyetli akma gerilmesi değerinden düşüktür. Testler sırasında tork tüp üzerinde tasarım problemleri görülmüştür. Tasarım probleminin giderilmesi için tork tüp tasarımı üzerinde değişiklik yapılmıştır. Bundan sonraki çalışmalarda tasarımda yapılan değişikliklerden dolayı, yapılan sonlu elemanlar analizlerinin tekrarlanması gerekmektedir. Sonlu elemanlar analizlerin tamamlanması ile beraber, üretim için teknik resimler güncellenerek, üretim gerçekleştirilmelidir. Tork tüpünün üretiminin tamamlanması ile tasarım üzerinde yapılan değişikliklerden dolayı, bazı yapısal testler yapılarak tork tüp tasarımının güvenilirliği sağlanmalıdır.
The aim of the project is designing of a torque tube of the helicopter. Firstly, Torque tupe systems were investigated and also torque tubes that were tested in İTU-ROTAM, were examined. General informations of ITU-LCH were explained. ITU-LCH is designed as a six passenger, two pilot, single engine conventional helicopter. Critical attritubes of the ITU-LCH have been identified as; safety,affordability,ease of use,lower noise levels, high reliability, low cost maintainability. Main features of the ITU-LCH have been identified as; high altitude operation capability over the high Anatolian Plateau, beaeringless hub system design, composite rotor blades, lower rotor RPM with lower tip speed and hence lower noise levels, lower disc loading with relatively lower power requirement. ITU-LCH designed to be versatile in its ability to perform operations such as hover,low speed loiter and long range cruise for a variety of mission profiles such as; personal travel applications, commercial applications, corporate applications and government applications. General informations about components and systems of ITU-LCH were given such as ; fuselage, landing gear, flight control system, propulsion system, transmission system,fuel system, electrical system and rotor system. The performance analysis of ITU-LCH was taken in different flight conditions. As the criteria of torque tupe design, attact angle of rotor blade conversion and effect of aerodynamic moments on rotor blade were investigated due to the performance analysis. Torque tube angle change must be around ±15°. In spite of the results of design criteria, torque tube design that easily assemblied to the rotor blade were completed. ITU-LCH has four blades so there are four torque tubes on rotor system. During the helicopter works, torque tubes should not crash.Torque tube included some parts such as; blade root shaft, tube input part, tubes, tubes’ stand, flexible couplins and blade cutaway part. Spherical bearing is on the blade root shaft. Displacements in the axial direction are restricted and freedom of the rotation provided.Tube input part and tubes transfer the force from swashplate mechanisim to blade. Tube input part rotates ±15°. Tubes’ stand connects tubes and flexible couplings. Flexible coupling, is rigid in the direction of torsion, is flexible in the direction of bending.Flexible couplings works as a multi-tier spring system.Blade cutaway part connects flexible couplings and blade. Material of blade root shaft, tube input part, tubes, tubes stand is aluminium. Material of flexible couplings and blade cutaway part is steel. Finite element model of torque tube were prepared. Appropriate boundary conditions of finite element model and finite element analysis with force application were carried out. The tensile strength values of torque tube parts obtained by finite element analysis lower than the safe yield stress value. Therefore, It can be said that structural design of torque tube is safe. In order to produce torque tube , technical drawings were prepared. 5 ABM prepared list of the necessary materials for production of torque tube.After the production, torque tube were assemblied on the test blade. Structural tests of torque tube were done by MTS tests equipment and other test equipments in ITU-ROTAM Structural Laboratory. Structural tests of torque tube were done for standard flight conditions and extreme flight conditions. During the standard flight conditions tests, force applied to torque tube which is assembled to blade. Blade angle of attack changed because of force. Boundary conditions were seen during this test. Steel beam’s dimension was calculated for the model of aerodynamic moment. Steel beam were tested in the MTS test equipments. Test results are as same as calculation of beam. Strain gages were glued high stress value point on torque tube parts using finite element analysis. Torque tube should work during minimum 75 hours (1500000 cycles) on helicopters. Torque tube on test blade connected steel beam with shaft. Helicopter rotation speed is 5.2 Hz. However, fatigue test were done at 1.5 Hz because of the MTS test equipments condition so fatigue test finished after 300 hours. Fatigue test were stopped after some cycles and strain values were evaluated using strain gages because any changing on torque tube parts have been seen. After the fatigue tests, stress values on the torque tube is lower than reliable yield stress. After the fatigue test of standard flight conditions, centrifugal test were done. Axial force, is two and three times centrifugal force, applied to torque tube. After the tests, stress on the torque tube is low. Stress on the torque tube is lower than reliable yield stress. For extreme flight conditions, steel beam’s dimensions were calculated again for model of the high aerodynamic moments. Static structural tests and fatigue test were done. During the static tests, torque tube with high aerodynamic moments effects were done so strain values were read by strain gages. Fatigue tests continued during 2000 cycles. After the static tests and fatigue test, there is any broken part. After these tests, torque tube is reliable for flight During the tests, design problems have been noticed. As a result of the force which applied to the torque tube, the angular variation of the torque pipe input part is not the same as angular variation of the angle of attack. However, angular variation of the angle of attack will be enough if the torque tube works like this. The other design problem is related to adaptor which is between torque tube’s tubes and tube input part. Torsion occurred on the torque tube’s tube because of the angular variation, Thus corrosion and erosion on the thread, is between tube input part and adaptor, occurred. Design of tube input part and adaptor changed because of design problem. The joint between this two parts is done shape instead of thread Finally, the finite element analysis will be repeated for the new design of torque tube. If the analysis results are suitable, the technical drawings will be updated and the torque tube will be produced. After the production, new torque tube design will be tested because of the modifications.
The aim of the project is designing of a torque tube of the helicopter. Firstly, Torque tupe systems were investigated and also torque tubes that were tested in İTU-ROTAM, were examined. General informations of ITU-LCH were explained. ITU-LCH is designed as a six passenger, two pilot, single engine conventional helicopter. Critical attritubes of the ITU-LCH have been identified as; safety,affordability,ease of use,lower noise levels, high reliability, low cost maintainability. Main features of the ITU-LCH have been identified as; high altitude operation capability over the high Anatolian Plateau, beaeringless hub system design, composite rotor blades, lower rotor RPM with lower tip speed and hence lower noise levels, lower disc loading with relatively lower power requirement. ITU-LCH designed to be versatile in its ability to perform operations such as hover,low speed loiter and long range cruise for a variety of mission profiles such as; personal travel applications, commercial applications, corporate applications and government applications. General informations about components and systems of ITU-LCH were given such as ; fuselage, landing gear, flight control system, propulsion system, transmission system,fuel system, electrical system and rotor system. The performance analysis of ITU-LCH was taken in different flight conditions. As the criteria of torque tupe design, attact angle of rotor blade conversion and effect of aerodynamic moments on rotor blade were investigated due to the performance analysis. Torque tube angle change must be around ±15°. In spite of the results of design criteria, torque tube design that easily assemblied to the rotor blade were completed. ITU-LCH has four blades so there are four torque tubes on rotor system. During the helicopter works, torque tubes should not crash.Torque tube included some parts such as; blade root shaft, tube input part, tubes, tubes’ stand, flexible couplins and blade cutaway part. Spherical bearing is on the blade root shaft. Displacements in the axial direction are restricted and freedom of the rotation provided.Tube input part and tubes transfer the force from swashplate mechanisim to blade. Tube input part rotates ±15°. Tubes’ stand connects tubes and flexible couplings. Flexible coupling, is rigid in the direction of torsion, is flexible in the direction of bending.Flexible couplings works as a multi-tier spring system.Blade cutaway part connects flexible couplings and blade. Material of blade root shaft, tube input part, tubes, tubes stand is aluminium. Material of flexible couplings and blade cutaway part is steel. Finite element model of torque tube were prepared. Appropriate boundary conditions of finite element model and finite element analysis with force application were carried out. The tensile strength values of torque tube parts obtained by finite element analysis lower than the safe yield stress value. Therefore, It can be said that structural design of torque tube is safe. In order to produce torque tube , technical drawings were prepared. 5 ABM prepared list of the necessary materials for production of torque tube.After the production, torque tube were assemblied on the test blade. Structural tests of torque tube were done by MTS tests equipment and other test equipments in ITU-ROTAM Structural Laboratory. Structural tests of torque tube were done for standard flight conditions and extreme flight conditions. During the standard flight conditions tests, force applied to torque tube which is assembled to blade. Blade angle of attack changed because of force. Boundary conditions were seen during this test. Steel beam’s dimension was calculated for the model of aerodynamic moment. Steel beam were tested in the MTS test equipments. Test results are as same as calculation of beam. Strain gages were glued high stress value point on torque tube parts using finite element analysis. Torque tube should work during minimum 75 hours (1500000 cycles) on helicopters. Torque tube on test blade connected steel beam with shaft. Helicopter rotation speed is 5.2 Hz. However, fatigue test were done at 1.5 Hz because of the MTS test equipments condition so fatigue test finished after 300 hours. Fatigue test were stopped after some cycles and strain values were evaluated using strain gages because any changing on torque tube parts have been seen. After the fatigue tests, stress values on the torque tube is lower than reliable yield stress. After the fatigue test of standard flight conditions, centrifugal test were done. Axial force, is two and three times centrifugal force, applied to torque tube. After the tests, stress on the torque tube is low. Stress on the torque tube is lower than reliable yield stress. For extreme flight conditions, steel beam’s dimensions were calculated again for model of the high aerodynamic moments. Static structural tests and fatigue test were done. During the static tests, torque tube with high aerodynamic moments effects were done so strain values were read by strain gages. Fatigue tests continued during 2000 cycles. After the static tests and fatigue test, there is any broken part. After these tests, torque tube is reliable for flight During the tests, design problems have been noticed. As a result of the force which applied to the torque tube, the angular variation of the torque pipe input part is not the same as angular variation of the angle of attack. However, angular variation of the angle of attack will be enough if the torque tube works like this. The other design problem is related to adaptor which is between torque tube’s tubes and tube input part. Torsion occurred on the torque tube’s tube because of the angular variation, Thus corrosion and erosion on the thread, is between tube input part and adaptor, occurred. Design of tube input part and adaptor changed because of design problem. The joint between this two parts is done shape instead of thread Finally, the finite element analysis will be repeated for the new design of torque tube. If the analysis results are suitable, the technical drawings will be updated and the torque tube will be produced. After the production, new torque tube design will be tested because of the modifications.
Açıklama
Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2012
Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2012
Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2012
Anahtar kelimeler
helikopter,
tork tüpü,
tasarım,
yapısal testler,
yapısal tasarım,
sonlu elemanlar,
helicopter,
finite elements analysis,
structural design,
structural tests,
design,
torque tube