مروری بر روش‌های بهبود و تعیین عملکرد آیرودینامیکی روتور بالگرد

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری، دانشگاه تربیت مدرس، تهران، ایران

2 دانشیار، دانشگاه تربیت مدرس، تهران، ایران

3 دانشیار، دانشگاه جامع امام حسین (ع)، تهران، ایران

چکیده

مقاله مروری حاضر به بررسی روش‌های تعیین عملکرد آیرودینامیکی روتور بالگرد می‌پردازد. ابتدا پژوهش‌های انجام‌گرفته در حوزه هندسه پره روتور بالگرد، دسته‌بندی و در ادامه تغییر جنس مواد مورداستفاده در پره‌های روتور بالگرد ارزیابی شده است. بهبود روزافزون توانایی رایانه‌ها در تحلیل مسائل و تغییر مواد مورداستفاده در طراحی و تولید پره‌ها از فلز به کامپوزیت و در نتیجه فراهم شدن امکان ساخت شکل‌های متنوع، علاقه‌مندی روزافزونی برای بهبود هندسه پره میان شرکت‌های سازنده بالگرد و محققان این حوزه به وجود آورده است که این امر نیازمند بهبود روش‌های شبیه‌سازی روتور بالگرد می‌باشد. بهبود این روش‌ها همواره از دو جنبه سرعت و دقت مورد تأکید محققان بوده است. در ابتدا روش‌های تحلیلی باهدف افزایش دقت نتایج، توسعه یافتند. سپس با استفاده از اجرای راه‌حل‌های عددی توسط رایانه‌ها، سرعت محاسبات افزایش یافت. در پژوهش‌های اخیر با ترکیب این دو روش و استفاده از نتایج حل تحلیلی به‌عنوان مقادیر اولیه در حل عددی، هزینه محاسباتی کاهش و دقت افزایش‌یافته است. همچنین تحقیقات اخیر بیشتر در جهت فرایندهای بهینه‌سازی سوق داده شده‌اند.

کلیدواژه‌ها


عنوان مقاله [English]

A Review of Methods to Improve and Determine the Aerodynamic Performance of Helicopter Rotor

نویسندگان [English]

  • seyed basir ajelleh 1
  • saeed karimian aliabadi 2
  • Mohammad Ali Jozvaziri 3
1 PhD student, Tarbiat Modares University, Tehran, Iran
2 Associate Professor, Tarbiat Modares University, Tehran, Iran
3 Associate Professor, Imam Hossein University (AS), Tehran, Iran
چکیده [English]

This review article examines the methods of determining the aerodynamic performance of the helicopter rotor. First, the researches carried out in the field of helicopter rotor blade geometry are categorized and then the change of material used in helicopter rotor blades is evaluated The increasing improvement in the ability of computers to analyze problems and the change of materials used in the design and production of blades from metal to composite, and as a result the possibility of making various shapes, has created an increasing interest in improving blade geometry among helicopter manufacturing companies and researchers in this field. This requires the improvement of helicopter rotor simulation methods. The improvement of these methods has always been emphasized by researchers in terms of speed and accuracy. At the beginning, analytical methods were developed with the aim of increasing the accuracy of the results. Then, using the implementation of numerical solutions by computers, the speed of calculations increased. In recent researches, by combining these two methods and using the analytical solution results as initial values in the numerical solution, the computational cost has been reduced and the accuracy has been increased. Also, recent researches have been more directed towards optimization processes.

کلیدواژه‌ها [English]

  • Helicopter Rotor
  • Aerodynamic Simulation
  • Blade Planform Optimization
1.        Brocklehurst, A., and Barakos, G. N. “A Review of Helicopter Rotor Blade Tip Shape”, J. Prog. Aerosp. Sci. Vol. 56, pp.35-74, 2013.
2.        Cook, C. V. “A Review of Tail Rotor Design and Performance”, VERTICA. Vol. 2, No. 3/4, pp.163-181, 1978.
3.        Perry, F. J. “Aerodynamics of the World Speed Record”, American Helicopter Society - 43rd Annual Forum Proceedings. Missouri, USA, 1987.
4.        Sałaciński, M., Puchała, K., Leski, A., Szymczyk, E., Hutsaylyuk, V., Bednarz, A., Synaszko, P., Kozera, R., Olkowicz, K., and Głowacki, D. “Technological Aspects of a Reparation of the Leading Edge of Helicopter Main Rotor Blades in Field Conditions”, J. Appl. Sci-Basel. Vol. 12, No. 9, Art. No. 4249, 2022.
5.        kocurek, J. D[A1] ., Tangler, J. L. “A prescribed Wake Lifting Surface Hover Performance Analysis”, American Helicopter Society - 32nd Annual Forum Proceedings. Washington DC., USA, 1976.
6.        Gessow, A., Myers, G. C. “Aerodynamics of the Helicopter”, Frederick Ungar Publishing Co., New York, United States, 1952.
7.        Landgrebe, A. J. “The Wake Geometery of a Hovering Helicopter Rotor and Its Influence on Rotor Performane”, American Helicopter Society - 28th Annual Forum Proceedings. Washington DC., USA, 1972.
8.        Landgrebe, A. J., Egolf, T. A. “Prediction of Helicopter IInduced Flow Velocities Using the Rotorcraft Waake Analysis”, American Helicopter Society - 32nd Annual Forum Proceedings. Washington DC., USA, 1976.
9.        Maskew, B. “Influence of Rotor Blade Tip Shape on Tip Vortex Shedding - An Unsteady, Inviscid Analysis”, American Helicopter Society - 36th Annual Forum Proceedings. Washington DC., USA, 1980.
10.     Summa, J. M. “Advanced Rotor Analysis Methods for the Aerodynamics of Vortex-Blade Interactions in Hover”, VERTICA. Vol. 9, No. 4, pp. 331-343, 1985.
11.     Tauber, M[A2] [A3] . E., Hicks, R. M. “Computerised Three-Dimensional Aerodynamic Design of a Lifting Rotor Blade”, American Helicopter Society - 36th Annual Forum Proceedings. Washington DC., USA, 1980.
12.     Grant, J. “Calculation of the Supercritical Flow Over the Tip Region of a Non-Lifting Rotor Blade at Arbitary Azimuth”, Technical Report. Royal Aircraft Establishment. Farnborough, 1977.
13.     Grant, J. “The Prediction of Supercritical Pressure Distributions on Blade Tips of Arbitrary Shapes”, VERTICA. Vol. 3, pp. 275-299, 1978.
14.     Tauber, M. E. “Computrized Aerodynamic Design of a Transonically “Quiet” Blade”, American Helicopter Society - 40th Annual Forum Proceedings. Crystal City., USA, 1984.
15.     Favier, D., Nsi-Mba, M., Barbi, C., Maresca, C. “A Free Wake Analysis for Heving Rotors and Advancing Propellers”, 11th European Rotorcraft Forum. London, England, pp. 29.1-29.22, 1985.
16.     Quackenbush, T. R. “Computational Studies in Low Speed Rotor Aerodynamics”, AHS Specialists. Meeting on Aerodynamics and Aeroacostics. Arlington, USA, 1987.
17.     Brocklehurst, A., Pike, A. C. “Reduction of BVI Noise Using a Vane Tip”, ”, AHS Specialists. Meeting on Aerodynamics and Aeroacostics. San Francisco, USA, 1994.
18.     Srinivasan, G. R., McCroskey, W. J., Baeder, J. D., Edwards, T. A. “Numerical Simulation of Tip Vortices of Wings in Subsonic and Transonic Flows”, J. AIRCRAFT. Vol. 26. No. 10, pp. 1153-1162, 1988.
19.     Caradonna, F. X., Tung, C. “Exprimental and Analysis Studies of a Model Helicopter Rotor in Hover”, NASA Technical Report Memorandum. TM-81232, 1981.
20.     Srinivasan, G. R., McCroskey, W. J. “Navier-Stokes Calculations of Hovering Rotor Flowfields”, J. AIRCRAFT. Vol. 25. No. 10, pp. 865-874, 1988.
21.     Duque, E. P. N. “A Numerical Analysis of the British Experimental Rotor Program Blade”, American Helicopter Society - 45th Annual Forum Proceedings. Boston, USA, 1989.
22.     Duque, E. P. N. “A Numerical Analysis of the British Experimental Rotor Program Blade”, 15th European Rotorcraft Forum. Amsterdam, Netherlands, 1989.
23.     Duque, E. P. N. “A Numerical Analysis of the British Experimental Rotor Programme Blade”, J. AM. HELICOPTER. SOC. Vol. 37, No. 1, pp. 46-54, 1992.
24.     Beddoes, T. S. “A 3-D Sepration Model for Arbitrary Planforms”, American Helicopter Society - 47th Annual Forum Proceedings. Phoenix, USA, 1991.
25.     Beddoes, T. S., “A Near Wake Dynamic Model”, American Helicopter Society - 48th Annual Forum Proceedings. Washington DC., USA, 1992.
26.     Brocklehurst, A., Beedy, J., Barakos, G., Badcock, K., Richards, B. “Experimental and CFD Investigation of Helicopter BERP Tip Aerodynamics”, Conference on Computational and Experimental Methods. University of Glasgow, Scotland, 2003.
27.     Rajagopalan, R. G., Lim, C. K. “Laminar Flow Analysis of a Rotor in Hover”, J. AM. HELICOPTER. SOC. Vol. 36, No. 1, pp. 12-23, 1991.
28.     Srinivasan, G. R., Beade, J. D., Obayashi, S., McCroskey, W. J. “Flowfield of a Lifting Hovering Rotor – a Navier-Stokes Simulation”, 16th European Rotorcraft Forum. Glasgow, Scotland, Paper No. I.3.5, pp. 1-15, 1990.
29.     Duque, E. P. N., Srinivasan, G. R. “Numerical Simulation of a Hovering Rotor Using Embedded Grids”, American Helicopter Society - 48th Annual Forum Proceedings. Washington DC., USA, 1992.
30.     Srinivasan, G. R., Raghavan, V., Duque, E. P. N., McCroskey, W. J. “Flowfield Analysis of Modern Helicopter Rotors in Hover by Navier-Stokes Method”, J. AM. HELICOPTER. SOC. Vol. 38, No. 3, pp. 3-13, 1993.
31.     Srinivasan, G. R., Beade, J. D. “TURNS: A Free Wake Euler/Navier-Stokes Numerical Method for Helicopter Rotors”, AIAA J. Vol. 31, No. 5, pp. 959-962, 1993.
32.     Duque, E. P. N., Dimanlig, A. C. B. “Navier-Stokes Simulation of the AH-66 (Comanche) Helicopter”, AHS Specialists’ Conference. San Francisco, USA, 1994.
33.     Aoyama, T., Kawachi, K., Saito, S. “Effect of Blade Tip Shape Planform on Shock Wave of Advancing Helicopter Blade”, J. AIRCRAFT. Vol. 32. No. 5, pp. 955-961, 1995.
34.     Lorber, P. F. “Aerodynamic Results of a Pressure Instrumented Model Rotor at the DNW”, J. AM. HELICOPTER. SOC. Vol. 36, No. 4, pp. 66-75, 1991.
35.     Wake, B.E., Beader, J. D. “Evaluation of a Navier-Stokes Analysis Method for Hover Performance Prediction”, J. AM. HELICOPTER. SOC. Vol. 41, No. 1, pp. 7-17, 1996.
36.     Ahmad, J. U., Duque, E. P. N. “Helicopter Rotor Blade Computation in Unsteady Flows Using Moving Overset Grids”, J. AIRCRAFT. Vol. 33. No. 1, pp. 54-60, 1996.
37.     Rezoni, P., d;Alascio, A., Kroll, N., Peshkin, D., Hounjet, M. H. L., Boniface, J. C., Vigevano, L., Allen, C. B., Badcock, K., Mottura, L., Schöll, E., Kokkalis, A. “EROS – A Common European Euler Code for the Analysis of Helicopter Rotor Flowfield”, PROG. AEROSP. SCI. Vol. 36, No. 5, pp. 437-485, 2000.
38.     Steijl, R., Barakos, G. “Sliding Mesh Algorithm for CFD Analysis of Helicopter Rotor-Fuselage Aerodynamics”, INT. J. NUMER. METH. FL. Vol. 58, No. 5, pp. 527-549, 2008.
39.     McAlister, K. W., Schuler, C. A., Branum, L., Wu, J. C. “3-D Wake Measurments Near a Hovering Rotor for Determining Profile and Induced Drag”, NASA Technical Report. Paper. 3577, 1995.
40.     40.Russell, J. W., Sankar, L. N., Tung, C. “High Accuracy Studies of the Tip Vortex Structure from a Hovering Rotor”, Fluid Dynamic Conference. Snowmass Village, USA, 1997.
41.     Liu, Z., Sankar, L. N., Hassan, A. A. “Alternation of the Tip Vortex Structure of a Hovering Rotor by Blowing”, 37th AIAA Aerospace Science Meeting and Exhibit. Reno NV., USA, 1999.
42.     Beaumier, P., Zibi, J., Costes, M. “CFD Drag and Power Prediction for a Rotor in Hover or Forward Flight - Formulation and First Applications”, J. AM. HELICOPTER. SOC. Vol. 42, No. 4, pp. 327-336, 1997.
43.     Beaumier, P., Chelli, E., Pahlke, K. “Navier-Stokes Prediction of Helicopter Rotor Performance in Hever Including Aero-Elastic Effects”, American Helicopter Society - 56th Annual Forum Proceedings. Virginia Beach, VA., USA, 2000.
44.     Beaumier, P., Chelli, E., Pahlke, K. “Navier-Stokes Prediction of Helicopter Rotor Performance in Hever Including Aero-Elastic Effects”, J. AM. HELICOPTER. SOC. Vol. 46, No. 4, pp. 301-309, 2001.
45.     Manke, J. W., Hirsh, J. E., Oh, B. K., Wicks, T. N., Dadone, L. “Improved Rotor Tip Relief Modeling by Coupling Comprehensive Rotor Analysis and Rotor Aerodynamics Codes”, ADV. ENG. SOFTW. Vol. 29, No. 3, pp. 475-480, 1998.
46.     Costes, M., LeBalleur, J. C., Gasparini, L., Vigevan, L., Hounjet, M. H. L., Kokkalis, A., Miller, J. V., Spruce, M., Pagano, A. Renzoni, P., Rocchetto, A., Toulmay, F. “Development of Common European Unsteady Full Potential CFD Code for Helicopter Rotor in Hover and Forward Flight”, American Helicopter Society – 53rd Annual Forum Proceedings. Virginia Beach, VA., USA, 1997.
47.     Joncheray, Ph. “Aerodynamics of Helicopter Rotor in Hover: The Lifting-Vortex Line Method Applied to Dihedral Tip Blades”, AEROSP. SCI. TECHNOL. Vol. 1, No. 1, pp. 17-25, 1997.
48.     Ahmed, S. R., Vidjaja, V. T. “Unsteady Panel Method Calculation of Pressure Distribution on a Bo105 Model Rotor Blade”, J. AM. HELICOPTER. SOC. Vol. 43, No. 1, pp. 47-56, 1998.
49.     Baeder, J. D. “Passive Design for Reduction of High-Speed Impolsive Rotor Noise”, J. AM. HELICOPTER. SOC. Vol. 43, No. 3, pp. 222-2346, 1998.
50.     Brocklehurst, A. “Application of CFD to Airfoils Blades and Helicopters”, The University of Glosgow Helicopter Study Weekend. Edzell, Scotland, 2003.
51.     Robinson, K., Brocklehurst, A. “BERP-IV Aerodynamics Performance and Flight Envelope”, 34th European Rotorcraft Forum. Liverpool, UK, 2008.
52.     Hu, H. “A Multigrid Navvier-Stokes CFD Code for Rotor Computations”, COMPUT. METHOD. APPL. M. Vol. 167, No. 1, pp. 127-137, 1998.
53.     Dindar, M., Lemnios, A., Shephard, M., Jansen, K., Kenwright, D. “Effect of Tip Vortex Resolution o UH-60A Rotor Blade Hover Performance Calculations”, American Helicopter Society - 54th Annual Forum Proceedings. Washington DC., USA, 1998.
54.     Philippe, J-J. “ONERA Makes Progress in Aerodyamics, Aeroelasticity and Acoustics”, Vertiflite. Vol. 38, No. 5, pp. 48, 1992.
55.     Kampa, K., Enenkl, B., Polz, G., Roth, G. “Aerodynamic Aspects in the Design of the EC135”, J. AM. HELICOPTER. SOC. Vol. 44, No. 2, pp. 83-93, 1997.
56.     Bebesel, M., Polz, G., Scholl, E. “Aerodynamic and Aeroelastic Layout of the ATR (Advanced Technology Rotor)”, American Helicopter Society - 55th Annual Forum Proceedings. Montral, Canada, 1999.
57.     Allongue, M., Marze, H. J., Potdevin, F. “The Quiet Helicopter-Forum Research to Reality”, American Helicopter Society - 55th Annual Forum Proceedings. Montral, Canada, 1999.
58.     Harihanan, N. S., Sankar, L. N. “First-Principle Based High-Order Methodolodies for Rotorcraft Flowfield Stidies”, American Helicopter Society - 55th Annual Forum Proceedings. Montral, Canada, 1999.
59.     Harihanan, N. S. “Rotary-Wing Wake Capturing: High Order Schemes Toward Minimizing Numerical Vortex Dissipation”, J. AIRCRAFT. Vol. 39, No. 5, pp. 822-829, 2002.
60.     Bhagwat, M. J., Leishman, J. G. “On the Relationship between Blade and Circulation and Tip Vortex Charactristics”, American Helicopter Society - 54th Annual Forum Proceedings. Washington DC., USA, 1998.
61.     Tang, L., Baeder, J. D. “Improved Euler Simulation of Hovering Rotor Tip Vorticies with Validation”, American Helicopter Society - 55th Annual Forum Proceedings. Montral, Canada, 1999.
62.     Devenport, W. J., Rife, M. C., Liapis, S. I., Follin, G. J. “The Structure and Development of a Wing-Tip Vortex”, J. FLUID. MECH. Vol. 312, pp. 67-106, 1996.
63.     Hall, C. M., Long, L. N. “High Order Accurate Simulation of Wake and Tip Vortex Flowfields”, American Helicopter Society - 55th Annual Forum Proceedings. Montral, Canada, 1999.
64.     Ahmed, J. U., Strawn, R. C. “Hovering Rotor and Wake Calculation with an Overset Grid Navier-Stokes Solver”, American Helicopter Society - 55th Annual Forum Proceedings. Montral, Canada, 1999.
65.     Strawn, R. C., Djomehri, M. J. “Computational Modeig of Hovering Rotor and Wake Aerodynamics”, American Helicopter Society - 57th Annual Forum Proceedings. Washington DC., USA, 2001.
66.     Strawn, R. C., Djomehri, M. J. “Computational Modelling of Hoverig Rotor and Wake Aerodyamics” J. AIRCRAFT. Vol. 39, No. 5, pp. 786-793, 2002.
67.     Brocklehurst, A. “Unsteady 2D Pitching Aerofoil in compressible Viscouse Flow”, Fluent CFD User Group Meeting, 2000.
68.     Yang, G. W., Zhuang, L. X. “Numerical Simulation of Rotor Flow in Hover”, J. AIRCRAFT. Vol. 37, No. 2, pp. 221-226, 2000.
69.     Pahlke, K., Chelli, E. “Calculation of Multibladed Rotors in Forward Flight”, 26th European Rotorcraft Forum. The Hague, Netherlands, pp. 48.1-48.18, 2000.
70.     D'Alascio, A., Pahlke, K., Castellin, C., Costes, M. “Application of the Navier-Stokes Codes Developed in the Framework of the Joined German/French CFD Research Program CHANCE”, 27th European Rotorcraft Forum. Moscow, Russia, pp. 38.1-38.10, 2001.
71.     Pomin, H., Wagner, S. “Navier-Stokes Analysis of Helicopter Rotor Aerodynamic i Hover and Forward Flight”, J. AIRCRAFT. Vol. 39, No. 5, pp. 739-749, 2002.
72.     Wachspress, D. A., Quackenbusk, T., Boschitsch, A. H. “First Principles Free Vortex Wake Analysis for Helicopters and Tiltrotors”, American Helicopter Society - 59th Annual Forum Proceedings. Phoenix AZ., USA, 2003.
73.     Wachspress, D. A., Quackenbusk, T., Boschitsch, A. H. “Rotorcraft International Aerodynamics Calculations with Fast Vortex/Fast Panel Method”, American Helicopter Society - 56th Annual Forum Proceedings. Virginia Beach VA., USA, 2000.
74.     Schreck, S. J., Faller, W. E., Robinson, M. C. “Unsteady Sepration Processes and Leading Edge Vortex Precursors: Pitch Rate and Reynolds Number Influence”, J. AIRCRAFT. Vol 39, No. 5, pp. 868-875, 2002.
75.     Ramaprian, B. R., Youxin, Zh. “Near Field of the Tip Vortex Behind on Oscillating Rectangular Wing”, AIAA J. Vol. 36, No. 7, pp. 1263-1269, 1998.
76.     Spentzos, A., Barakos, G. N., Badcock, K. J., Richards, B. E., Wernet, P., Schreck, S. J., Raffel, M. “CFD Investigation of 2D and 3D Dyamic Stall”, 4th AHS Specialists’ Conference on Aeromechanics. San Francisco, USA, pp. 2.4:1-2.4:20, 2004.
77.     Beedy, J. “Numerical Study of the Flow Field around the Tip of Oscillating Wings”, Proceeding of the University of Glasgow Helicopter Study Weekend. The Burn, Scotland, 2003.
 
78.     Barakos, G., Steijl, R., Badcock, K., Brocklehurst, A. “Development of a CFD Capability for Full Helicopter Engineering Analysis”, 31st European Rotorcraft Forum. Florence, Italy, 2005.
79.     Kang, H. J., Kwon, O. J. “Viscous Flow Simulation of a Lifting Rotor in Hover Using Unstructured Adaptive Mesh”, American Helicopter Society - 57th Annual Forum Proceedings. Washington DC., USA, 2001.
80.     Kang, H. J., Kwon, O. J. “Effect of Wake Adaption on Rotor Hover Simulation Using Unstructured Meshes”, J. AIRCRAFT. Vol. 38, No. 5, pp. 868-877, 2001.
81.     Morvant, R., Badcock, K. J., Barakos, G. N. “Airfoil - Vortex Interaction Simulation Using the Compressible Vorticity Confinnement Method” 29th European Rotorcraft Forum. Friedrichschafen, Germany, 2003.
82.     Tsukahara, T., Ota, T.; Obukata, M., Araki, R., Obayashi, S., Nakahasi, K. “Numerical Analysis around Rotor Blade by Vortex Confinement” American Helicopter Society - 58th Annual Forum Proceedings. Montreal Quebec, Canada, 2002.
83.     Biava, M., Vigevano, L. “Assessment of the Vorticity Confinement Technique Applied to Rotorcraft Flows” AIAA 7TH APPLIED AERODYNAMICS CONFERENCE. Orlando, Florida, 2003.
84.     Hu, G., Grossman, B., Steinhoff, J. “Numerical Method for Vorticity Conference in Compressible Flow” AIAA J. Vol. 40, No. 10, pp. 1945-1953, 2002.
85.     Wenren, Y., Fan, M., Wang, L., Xiao, M., Steinhoff, J. “Application of Voticity Confinement to Prediction of the Flow Over Complex Bodies” AIAA J. Vol. 41, No. 5, pp. 809-816, 2003.
86.     Canonne, E., Benoit, C., Jean Faivre, G. “Cylindrical Mesh Adaption for Isolated Rotors i Hover” American Helicopter Society - 58th Annual Forum Proceedings. Montreal Quebec, Canada, 2002.
87.     Brown, R. E. “Rotor Wake Modeling for Flight Dynamics Simulation of Helicopters” AIAA J. Vol. 38, No. 1, pp. 57-63, 2000.
88.     Brown, R. E., Leishman, J. G., Newman, S. J., Perry, F. J. “Blade Twist Effects on Rotor Behaviour in the Vortex Ring State” 28th European Rotorcraft Forum. Bristol, England, 2002.
89.     Line, A. J., Brown, R. E. “High Resolution Wake Modeling Using a Semi-Lagrangian Adaptive Grids Formulation” 29th European Rotorcraft Forum. Friedrichschafen, Germany, 2003.
90.     Brown, R. E., Line, A. J., Ahlin, G. A. “Numerical Investigation into the Vortex Ring State Phenomenon” Proceeding of the University of Glasgow Helicopter Study Weekend. The Burn, Scotland, 2004.
91.     Hu, H. “Computational Analysis of Effects of Blade Shapes on Tip-Vortex” ADV. ENG. SOFTW. Vol. 34, No. 5, pp. 279-286, 2003.
92.     Le Pape, A., Beaumier, P. “Numerical Optimization of Helicopter Rotor Aerodyamic Performance in Hover” 29th European Rotorcraft Forum. Friedrichschafen, Germany, 2003.
93.     Bhagwat, M., Moulton, M. A.,; Caradonna, F. X. “Recent Advances in the Embedded-Wake Approach to Hover Performance Prediction” 4th AHS Specialists’ Conference on Aeromechanics. San Francisco, USA, pp. 5.1:1-5.1:17, 2004.
94.     Aiken, E. W., Ormisto, R. A., Young, L. A. “Future Directions in Rotorcraft Technology at NASA Ames Research Center” American Helicopter Society - 56th Annual Forum Proceedings. Virginia Beach VA., USA, 2000.
95.     Johnson, C. J., Barakos, G. N. “Development and Demonstration of a Framework for Optimisinng Aspects of Rotor Blades in Forward Flight” AIAA APPLIED AERODYNAMICS CONFERENCE. Orlando, Florida, 2011.
96.     Vu, N. A., Lee, J. W. “Aerodynamic Design Optimization of Helicopter Rotor Blades Including Airfoil Shape for Forward Flight” AEROSP. SCI. TECHNOL. Vol. 42, pp. 106-117, 2014.
97.     Narducci, R. “Hover Performance Assessment of Sevral Tip Shape Using OVERFLOW” 53rd AIAA Aerospace Sciences Meeting. Florida, USA, 2015.
98.     Wilke, G. “Applying Multi-Objective Variable-Fidelity Optimization Techniques to Industrial Scale Rotors: Blade Design for CleanSky” 41st European Rotorcraft Forum. Minuch, Germany, 2015.
99.     Johnson, C., Woodgate, M., Barakos, G. N. “Optimising Aspects of BERP-Like Rotors Using Frequency-Domain Methods” Advances in Fluid-Structure Interaction. Greece, pp. 235-267, 2016.
100.  Jacobson, K. E., Smith, M. J. “Carefree Hybrid Methodology for Rotor Hover Performance Analysis” J. AIRCRAFT. Vol 55, No. 1, pp. 1-14, 2017.
101.  Darwish, S. H., Abdelrahman, M. M., Elmekawy, A. M. N., Elsayed, K. “Aerodynamic Low Fidelity Shape Optimization of Helicopter Rotor Blades in Hover Using Genetic Algorithms and the Adjoint Method” AIAA Aerospace Sciences Meeting. Florida, USA, 2018.
102.  Zhou, C., Sankar, L. N., Griffin, P. “Effects of Anhedral on S-76 Hover Aerodynamics” AIAA Scitech Forum. California, USA, 2019.
103.  Wang, L., Diskin, B., Beidron, R. T., Nielsen, E. J., Bauchau, O. A. “Evaluation of High-Fidelity Multidisciplinary Sensitivity-Analysis Framework for Multipoint Rotorcraft Optimization” J. AIRCRAFT. Vol. 57, No. 5, pp. 830-842, 2020.
104.  Fitzgibbon, T. A. “Advanced Rotor Blade Design Based on High-Fidelity Computational Fluid Dynamics” PhD Thesis, University of Glasgow, College of Science and Engineering, 2021.
105.  Okumuş, O., Şenipek, M., Ezertaş, A. “Multi-Objective Multi-Fidelity Aerodynamic Optimization of Helicopter Rotor” AIAA Scitech Forum. San Diego, USA, 2022.
106.  Johnson, W., "Technology Drivers in the Development of CAMRAD II." American Helicopter Society Aeromechanics Specialists Conference. San Francisco, USA. 1994.
107.  Afshari, A., Karimian, S. M. H. “A New Blade Tip Geometry to Improve Aerodynamic Performance and Acoustic Noise of Helicopter Blade in Hovering Flight” AEROSP. SCI. TECHNOL. Vol. 135, pp. 108197, 2023.