ISTANBUL TECHNICAL UNIVERSITY FACULTY OF AERONAUTICS AND ASTRONAUTICS PERFORMANCE CALCULATION FOR HELICOPTER BLADE UNDER HOVER CONDITION GRADUATION PROJECT Hüseyin DİKEL Department of Aeronautical Engineering Thesis Advisor: Assis. Prof. Dr. Özge ÖZDEMİR SEPTEMBER 2020 i ISTANBUL TECHNICAL UNIVERSITY FACULTY OF AERONAUTICS AND ASTRONAUTICS PERFORMANCE CALCULATION FOR HELICOPTER BLADE UNDER HOVER CONDITION GRADUATION PROJECT Hüseyin DİKEL (110150005) Department of Aeronautıcal Engineering Thesis Advisor: Assis. Prof. Dr. Özge ÖZDEMİR SEPTEMBER 2020 iii Hüseyin DİKEL, student of ITU Faculty of Aeronautics and Astronautics student ID 110150005, successfully defended the graduation entitled “PERFORMANCE CALCULATION FOR HELICOPTER BLADE UNDER HOVER CONDITION” which he prepared after fulfilling the requirements specified in the associated legislations, before the jury whose signatures are below. Thesis Advisor: Assis. Prof. Dr. Özge ÖZDEMİR .............................. İstanbul Technical University Jury Members: Prof. Dr. Metin Orhan KAYA ............................... İstanbul Technical University Prof. Dr. Zahit MECİTOĞLU ............................... İstanbul Technical University Date of Submission : 07 September 2020 Date of Defense : 14 September 2020 v To my big family, iii iv FOREWORD Önsöz bölümünün içerisindeki metinler 1 satır aralıklı yazılır. Tezin ilk sayfası niteliğinde yazılan önsöz ikisayfayı geçmez. Tezi destekleyen kurumlara ve yardımcı olan kişilere bu kısımdateşekkür edilir. Önsöz metninin altında sağa dayalı olarak ad-soyad, sola dayalı olarak ay, yıl biçiminde tarih yazılır. Bu iki unsur aynı hizada olur. September 2020 Hüseyin Dikel v vi TABLE OF CONTENTS Page FOREWORD .............................................................................................................. v TABLE OF CONTENTS ......................................................................................... vii ABBREVIATIONS ................................................................................................... ix LIST OF TABLES .................................................................................................... xi LIST OF FIGURES ................................................................................................ xiii ÖZET ......................................................................................................................... xv SUMMARY ............................................................................................................. xvi 1. INTRODUCTİON .............................................................................................. 1 1.1 Purpose of Thesis ............................................................................................... 3 1.2 Literature Review ............................................................................................... 3 2. HYPOTHESİS OF COAXIAL ROTOR .......................................................... 8 2.1 Case 1 ................................................................................................................. 9 2.2 Case 2 ............................................................................................................... 10 2.3 Case 3 ............................................................................................................... 10 2.4 Case 4 ............................................................................................................... 14 2.5 Figure of Merit Formulation ............................................................................ 16 3. THE COAXIAL ROTOR PARAMETERS CALCULATION .................... 19 3.1 Graphic of the Thrust to the Power Calculation ............................................... 21 3.2 Graphic of the Ratio of Thrust to Power with Thrust ..................................... 24 3.3 Graphic of the Figure of Merit ......................................................................... 26 3.4 Codes ................................................................................................................ 29 3.4.1 Code for rotor 1 ......................................................................................... 29 3.4.2 Code for rotor 2 ......................................................................................... 30 4. CONCLUSIONS .............................................................................................. 31 5. REFERENCES ................................................................................................. 32 vii viii ABBREVIATIONS A : Rotor disk area(according to diameter) 푪풅ퟎ : Zero lift drag coefficient 푪풍휶 : Sectional lift curve slope 푪푷 : Rotor power coefficient 푪푻 : Rotor thrust coefficient 푪푻풍 : Rotor thrust coefficient on lower rotor 푪푻풖 : Rotor thrust coefficient on upper rotor 푪푾 : Weight coefficient DL : Disk loading 풅ퟏ, 풅ퟐ : Profile drag formula coefficients FM : Figure of merit P : Rotor power 푷풊 : Induced power 푷풊풅풆풂풍 : Ideal power 푷풎풆풂풔 : Measured system power 푷ퟎ : Profile power R : Blade radius 푻 : Rotor thrust 푻풍 : Thrust on lower rotor 푻풖 : Thrust on upper rotor 풗풆 : Average effective induced velocity 풗풍 : Induced velocity of lower rotor 풗풖 : Induced velocity of upper rotor 푊 : Weight of helicopter on rotor 풘풍 : Slipstream velocity of lower rotor 훀 : Rotational speed of rotor 휶 : Angle of attack of blades 휿 : Rotor induced power factor for a single 휿풊풏풕 : Rotor interference induced power factor for a coaxial 흆 : Air density 흈 : Total solidity for one rotor ix x LIST OF TABLES Page Table 2.1: The interference-induced power factor for different coaxial rotor helicopter condition (ref. 7). ...……………………………………….….15 Table 3.1: The values of parameters according to Harrington’s rotors(ref. 5). ...….20 Table 3.2: The values of same parameters for both Harrington’s rotors(ref. 7). ..…21 xi xii LIST OF FIGURES Page Figure 1.1: Kamov KA-50 helicopter (ref. 3)………………………………………..2 Figure 1.2: Henry Bright’s coaxial helikopter design patent in 1859 (ref. 2)………. 4 Figure 1.3: The first American coaxial helicopter XH-44 (ref. 11)………………… 5 Figure 1.4: The Langley full-scale tunnel with a single rotor helicopter (ref. 12)….. 6 Figure 1.5: Experimental coaxial rotor of the National Defense Academy (ref. 2)… 7 Figure 1.6: The unmanned aerail vehicle named QH-50 from American Navy on Vietnam War(ref. 8)……………………………………………………………. 8 Figure 2.1: Flow model of corotation in the same plane at equal thrusts (ref. 7)…… 9 Figure 2.2: Flow model of operating coaxial rotor with slipstream between the lower rotor and the upper rotor (ref. 7)………………………………………………. 11 Figure 3.1: NACA 0012 airfoil section(ref. 9)…………………………………….. 20 Figure 3.2: The thrust to power graphic for Harrington rotor 1(ref. 7)……………. 22 Figure 3.3: The calculated thrust to power graphic on Matlab for Harrington rotor 1……………………………………………………………………………….. 22 Figure 3.4: The thrust to power graphic for Harrington rotor 2(ref. 7)……………. 23 Figure 3.5: The calculated thrust to power graphic on Matlab for Harrington rotor 2……………………………………………………………………………….. 23 Figure 3.6: Ratio of thrust to power with thrust graphic for Harrington rotor 1(ref. 7)………………………………………………………………………………. 24 Figure 3.7: The calculated ratio of thrust to power with thrust graphic on Matlab for Harrington rotor 1……………………………………………………………... 25 Figure 3.8: Ratio of thrust to power with thrust graphic for Harrington rotor 2(ref. 7)………………………………………………………………………………. 25 Figure 3.9: The calculated ratio of thrust to power with thrust graphic on Matlab for Harrington rotor 2……………………………………………………………... 26 Figure 3.10: The Figure of merit to blade loading coefficient graphic for Harrington rotor 1(ref. 7)…………………………………………………………………...27 Figure 3.11: The calculated the figure of merit to blade loading coefficient graphic on Matlab for Harrington rotor 1……………………………………………… 27 Figure 3.12: The Figure of merit to blade loading coefficient graphic for Harrington rotor 2(ref. 7)………………………………………………………………….. 28 Figure 3.13: The calculated the figure of merit to blade loading coefficient graphic on Matlab for Harrington rotor 2……………………………………………… 28 xiii xiv ASILI KALMA DURUMUNDA HELİKOPTER PALLERİNİN PERFORMANS HESAPLANMASI ÖZET Koaksiyel(çift rotorlu sistem) rotorlu helikopterler günümüzde çok tercih edilen helikopter çeşitleri olmasalar da eski de değillerdir. Tek rotorlu helikopterlere göre en büyük avantajarı, aynı ağırlık için gereken pallerinin boyutlarının daha küçük olmasıdır. Hızlı ve yüksek savaş performansına sahiptirler. Kuyruklarında rotor bulunmamasından kaynaklı olarak diğer helikopterlere göre daha fazla hayatta kalabilme kabiliyetleri bulunmaktadır. Bu nedenle, bu çalışmada, tek rotorlu ya da tandem helikopterlerin yanı sıra, koaksiyel rotorlu helikopterlerdeki pallerin performans analizleri ve tek rotorlu helikopterlere göre karşılaştırma analizleri incelenmiştir. Öncelikle; incelenen analizlerde, koaksiyel rotor performansı, momentum teori kullanılarak bulunan yeni formülasyonlarla değerlendirilmiştir. Daha sonra karşılaştırmak için koaksiyel rotorları hesaplamalarında en çok bilinen ve NACA’da yaklaşık bir yüzyıl önce Harrington tarafından yapılan ölçüm çalışmaları kullanılmıştır. Daha sonra; incelenen analizde, ilk olarak, koaksiyel rotor sistemin farklı güç katsayılarına göre itki katsayısı hesaplamaları yapılmıştır. Aynı teknik kullanılarak farklı ağırlık katsayılarına göre itki katsayısının güç katsayına göre oranı hesaplanmıştır. Üçüncü ve karşılaştırması yapılan sonuncu performans analizi olan farklı pal yüklenme katsayısına