Jimenez-Garcia, Antonio (2018) Development of ... - Enlighten: Theses - University of Glasgow

358 Pages·2017·41.32 MB·English

Jimenez-Garcia, Antonio (2018) Development of predictive methods for
tiltrotor flows. PhD thesis.

http://theses.gla.ac.uk/8603/

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Development of Predictive Methods for
Tiltrotor Flows
by
Antonio Jimenez-Garcia
A thesissubmittedinpartial
fulfillmentoftherequirements for
thedegreeofDoctorofPhilosophy
UniversityofGlasgow
SchoolofEngineering
July2017
c 2017
(cid:13)
AntonioJimenez-Garcia
Declaration
I hereby declare that this dissertation is a record of work carried out in the School of Engi-
neeringattheUniversityofLiverpoolduringtheperiodfromJanuary2014toAugust2015,andat
the University of Glasgow during the period from September 2015 to July 2017. The dissertation
isoriginalin contentexceptwhere otherwiseindicated.
July2017
...............................................................
(AntonioJimenez-Garcia)
i
Abstract
This thesis presents evidence on the ability of grid-based, Computational Fluid Dynamics
methodsbasedon theUnsteadyReynoldsAveragedNavier-Stokes equationstoaccurately predict
axial flightperformance ofrotors withmodestcomputerresources. Three well-studiedblades,the
B0-105, S-76, and PSP main rotor blades, are used and results are compared with experimental
data. Likewise,performanceanalysesoftheJORPpropellerandXV-15tiltrotorbladesarecarried
out,respectively,aimingtovalidatetheemployedCFD methodforsuchrelevantflows.
Validation of the HMB3 CFD solver for complete tiltrotors is also presented. The aim is to
assess the capability of the present CFD method in predicting tiltrotor airloads at different flight
configurations. In this regard, three representative cases of the ERICA tiltrotor were selected,
corresponding to aeroplane, transition corridor, and helicopter modes, covering most modes of
tiltrotorflight.
Aerodynamic optimisationof tiltrotorblades with high-fidelity computational fluid dynam-
ics coupled with a discrete adjoint method is also carried out. This work shows how the main
blade shape parameters influence the optimal performance of the tiltrotor in helicopter and aero-
planemodes,andhowa compromisebladeshapecan increasetheoveralltiltrotorperformance.
Finally, the implementationand validationof an efficient, high-order, finite-volumescheme
(up to 4th-order of spatial accuracy) in the HMB3 CFD solver is presented. The scheme shows
a higher level of accuracy if compared with the standard-MUSCL, and 4th-order accuracy was
achieved on Cartesian grids. Furthermore, a significantly high spectral resolution (dispersion and
dissipation)ofthenewschemeisobserved. Two-andthree-dimensionaltestcaseswereconsidered
to demonstrate the new formulation. Results of the steady flow around the 7AD, S-76, JORP
propeller, and XV-15 blades showed a better preservation of the vorticity and higher resolution
of the vortical structures compared with the standard MUSCL solution. The method was also
demonstrated for three-dimensional unsteady flows using overset and moving grid computations
for the UH-60A rotor in forward flight and the ERICA tiltrotor in aeroplane mode. For medium
grids,thenewhigh-orderschemeaddsCPUandmemoryoverheadsof22%and23%,respectively.
Theparallel performanceoftheschemeisfair butcan befurtherimproved.
ii
Publications
Journal Articles
Jimenez-Garcia, A., and Barakos, G.N., “CFD Analysis of HoverPerformance of Ro-
•
tors at Full-and Model-Scale Conditions”, The Aeronautical Journal, Vol. 120, No.
1231, 2016,pp. 1386-1424,doi: 10.1017/aer.2016.58.
Jimenez-Garcia, A., and Barakos, G.N., “Accurate Predictions of Rotor HoverPerfor-
•
manceatLowandHighDiscLoadings”,JournalofAircraft,AdvanceOnlinePublica-
tion,2017,doi: 10.2514/1.C034144.
Jimenez-Garcia,A.,andBarakos,G.N.,“NumericalSimulationsontheERICATiltro-
•
tor”, AerospaceScienceand Technology,Vol. 64,2017, pp. 171-191,
doi: 10.1016/j.ast.2017.01.023.
Jimenez-Garcia, A., Barakos, G.N., and Gates, S., “TiltrotorCFD Part I- Validation”,
•
The AeronauticalJournal,Vol. 121,No. 1239,2017,pp. 577-610,
doi: 10.1017/aer.2017.17.
Jimenez-Garcia, A., Biava, M., Barakos, G.N., Gates, S., Baverstock, K., and Mullen,
•
P., “TiltrotorCFD Part II - AerodynamicOptimisationof TiltrotorBlades”, The Aero-
nauticalJournal,Vol. 121,No. 1239,2017,pp. 611-636,doi: 10.1017/aer.2017.21.
Jimenez-Garcia,A.,andBarakos,G.N.,“AssessmentofaHigh-OrderMUSCLMethod
•
for Rotor Flows”, International Journal for Numerical Methods in Fluids, Under Re-
view.
Publications in Conference Proceedings
Jimenez-Garcia, A., and Barakos, G.N., “Hover Predictions on the S-76 Rotor Using
•
HMB2”, Proceedings of the 53rd Aerospace Sciences Meeting, Kissimmee, Florida,
USA, AIAA-2015-1712,2015,doi: 10.2514/6.2015-1712.
Jimenez-Garcia, A., and Barakos, G.N., “Numerical Simulation of the ERICA Tiltro-
•
torUsingHMB2”, Proceedingsof the41stEuropeanRotorcraftForum,Munich,Ger-
many,ERF-2015-42,2015,pp. 1-15.
Jimenez-Garcia, A., and Barakos, G.N., “Hover Predictions of the S-76 Rotor Using
•
HMB2 - Model to Full Scale”, Proceedings of the 54th Aerospace Sciences Meeting,
San Diego,California,USA, AIAA-2016-0299,2016,doi: 10.2514/6.2016-0299.
iii
Jimenez-Garcia, A., and Barakos, G.N., “CFD Simulations of the ERICA Tiltrotor
•
UsingHMB2”, Proceedingsof the54thAerospaceSciences Meeting,San Diego,Cal-
ifornia, USA, AIAA-2016-0329,2016,doi: 10.2514/6.2016-0329.
Jimenez-Garcia,A.,andBarakos,G.N.,“AerodynamicStudyofTiltrotorBlades”,Pro-
•
ceedings of the 42nd European Rotorcraft Forum, Lille, France, ERF-2016-56, 2016,
pp. 1-16.
Jimenez-Garcia, A., Colonia, S., and Barakos, G.N., “Accurate Predictions of Hover-
•
ing Rotor Flows Using CFD”, Proceedings of the 55th Aerospace Sciences Meeting,
Grapevine, Texas,USA, AIAA-2017-1666,2017,doi: 10.2514/6.2017-1666.
Jimenez-Garcia, A., and Barakos, G.N., “Implementation of High-Order Methods in
•
the HMB CFD Solver”, Proceedings of the 73rd American Helicopter Society Annual
Forum,AHS, Fort Worth,Texas,USA, 2017.
Jimenez-Garcia,A.,andBarakos,G.N.,“NumericalSimulationsofRotorsUsingHigh
•
Fidelity Methods”, Proceedings of the 35th Applied Aerodynamics Conference, Den-
ver, Colorado, USA, AIAA-2017-3053,2017,doi: 10.2514/6.2017-3053.
Jimenez-Garcia, A., andBarakos, G.N., “TowardsHigh-OrderMethodsforRotorcraft
•
Applications”,Proceedingsofthe43rdEuropeanRotorcraftForum,Milan,Italy,ERF-
2017-516,2017,pp. 1-16.
Jimenez-Garcia, A., and Barakos, G.N., “Numerical Simulations on the PSP Rotor
•
Using HMB3”, Proceedings of the 56th Aerospace Sciences Meeting, Kissimmee,
Florida, USA, 2018,Abstract Accepted.
Other Conferences/Symposia
Jimenez-Garcia, A., and Barakos, G.N., “Numerical Simulations of Helicopters and
•
Tiltrotors using the HMB2 Solver”, 1st U.K. Vertical Lift Network (VLN) Technical
Workshop,Oakmere, Cheshire, U.K, 2015.
Jimenez-Garcia, A., and Barakos, G.N., “Aerodynamic and Optimisation Study of
•
Tiltrotor Blades”, 2nd U.K. Vertical Lift Network (VLN) Technical Workshop, Pott
Shrigley,Cheshire, U.K,2016.
Jimenez-Garcia, A., and Barakos, G.N., “CFD Simulations on the ERICA Tiltrotor
•
using HMB3”, 2nd International Scientific Conference Science of the Future, Kazan,
Russia, 2016.
Jimenez-Garcia, A., and Barakos, G.N., “A High-OrderMethod for Rotorcraft Flow”,
•
3rd U.K. Vertical Lift Network (VLN) Technical Workshop, Pott Shrigley, Cheshire,
U.K, 2017.
iv
Technical Reports
Jimenez-Garcia, A., “D4.1a HMB Validation I”, HiperTilt Project - Technology Strat-
•
egy Board(TSB), January 2014.
Jimenez-Garcia,A.,“D4.1bHMBValidationII”,HiperTiltProject-TechnologyStrat-
•
egy Board(TSB), April2015.
Jimenez-Garcia,A.,“D4.5AeroacousticMethod”,HiperTiltProject-TechnologyStrat-
•
egy Board(TSB), June2015.
Jimenez-Garcia, A., “D4.6 Aeroelasticity Study using HMB2”, HiperTilt Project -
•
TechnologyStrategyBoard(TSB), July2015.
Jimenez-Garcia, A., “High-Order Schemes with HMB3”, Technical Note TN16-008,
•
CFD Laboratory,UniversityofGlasgow,May2016.
Jimenez-Garcia, A., “D5.1 CFD Simulations on the ERICA Tiltrotor using HMB2”,
•
HiperTiltProject- TechnologyStrategyBoard(TSB), June2016.
Placements
Leonardo Helicopters, Aerodynamics Department, Lysander Rd, Yeovil BA20 2YB,
•
12–15January 2015. ”IntegrationoftheBENPand HMBSolvers”
Leonardo Helicopters, Aerodynamics Department, Lysander Rd, Yeovil BA20 2YB,
•
11–15May 2015. ”ComputingTiltrotorCases usingtheHMBSolver”
v
Acknowledgements
First and foremost, I would like to thank my supervisor Professor George Barakos for his
constant guidance, support, encouragement, and technical knowledge throughout this work. His
contagious enthusiasm and passion for Computational Fluid Dynamics kept me highly motivated
and made this thesis a reality. I am also very grateful to Dr. Mark Woodgate and Dr. Massimo
Biava for sharing their tremendous expertise and experience in numerical methods and for the
numerous discussions we had on high-order and adjoint methods. Special thanks for Dr. Rene
Steijl, who advised me and shared his knowledgeon rotorcraft flows at all moments. I would like
also to extend my gratitude to all members of the CFD lab for creating a family-supportivework
environment and making me feel at home. The time spent with Dr. Nick Tantaroudas, Dr. Vasilis
Pastrikakis, Dr. Simone Colonia, Dr. Vladimir Leble, Jur Mourits, and many others, is of great
value.
ThefinancialsupportoftheHiperTiltProjectoftheU.K.TechnologyStrategyBoard(TSB)
and Leonardo Helicopters under Contract Nr. 101370 is gratefully acknowledged. Many thanks
should go to Alessandro Scandroglio, Dr. Florent Dehaeze, Stuart Gates, Karl Baverstock, and
PaulMullenofLeonardoHelicoptersfortheircontributionstotheacousticand optimisationwork
and forhostingmeduringmyplacementsin theAcousticand AerodynamicsDepartments.
The use of the clusters Chadwick of the University of Liverpool and the EPSRC funded
ARCHIE-WeSt High Performance Computer (www.archie-west.ac.uk),EPSRC grant no.
EP/K000586/1is gratefullyacknowledged.
In addition, I would like to thank to all members of Scottish International Youth Charity
Organisation, and its football branch for being my second family and providing an unconditional
support in every aspect beyond sports. A very special thank you goes to my housemate, football
manager, and friend Abdul Duane Lawal. The support and friendship of Francisco Suarez, Juan
Pablo Paez, Miguel Ballesteros, Juan Molina and Manuel Jesus Algarin must be fully recognised
and appreciated. GraciasAmigos.
Most importantly, I would like to thank my parents Antonio and Rosa, my brothers Juan
Miguel and Eduardo and my fiance Sonia for their endless love and patience during these years
and for supporting me in every hard situation. Vuestro amor y comprensio´n en estos an˜os ha sido
laluzquemehaguiadocadad´ıa. Papa´,Mama´,JuanMiguel,EduardoySonia,osquierocontodo
mi corazo´n. Graciaspor creer en mi.
vi
Contents
1 Introduction 1
1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 LiteratureSurvey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2.1 ValidationDataRelated to HelicopterRotors . . . . . . . . . . . . . . . . 3
ModellingRotors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
CFD Efforts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
S-76 Rotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.2.2 ValidationDataRelated to Propellers . . . . . . . . . . . . . . . . . . . . 16
1.2.3 ValidationDataRelated to Tiltrotors . . . . . . . . . . . . . . . . . . . . . 18
1.2.4 AerodynamicOptimisationofTiltrotorBlades . . . . . . . . . . . . . . . 27
1.2.5 ValidationDataforAeroacoustics . . . . . . . . . . . . . . . . . . . . . . 29
1.2.6 High-OrderDiscretisationMethodsforCFD . . . . . . . . . . . . . . . . 32
1.3 SummaryofFindings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
1.4 ObjectivesoftheThesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
1.5 OutlineoftheThesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
2 HMB3 Solver 37
2.1 CFD Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
2.2 VariableExtrapolation-MUSCLApproach . . . . . . . . . . . . . . . . . . . . . . 38
2.3 TurbulenceModelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
2.3.1 TheReynolds-Averaging . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
TimeAveraging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
2.3.2 RANS and URANS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
2.3.3 TurbulenceModels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
k-ωand SST Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
k-ωSST-γModel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
γ-Re Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
θt
TransitionCriteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
2.4 AerodynamicModels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.5 OversetGridMethod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
2.6 OptimisationFramework . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
2.7 VisualisationofVortical Flows . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
3 Aeroacoustic Method 55
3.1 HelicopterFfowcs Williams-Hawkings . . . . . . . . . . . . . . . . . . . . . . . . 55
3.2 BENPAcoustics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
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3.2.1 AeroacousticFilefortheS-76 RotorBladeinHover . . . . . . . . . . . . 68
3.2.2 AeroacousticFilefortheAW-139RotorBlade inForward Flight . . . . . . 70
4 High-Order Method 79
4.1 High-orderFormulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
4.2 Green-Gauss Formulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
4.3 MemoryOverhead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
4.4 OrderofAccuracy in1D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
4.5 ImplementationDetails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
4.6 FourierAnalysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
4.7 VortexTransportedbyUniformflow . . . . . . . . . . . . . . . . . . . . . . . . . 87
5 ValidationofHMBforHelicopterBlades inHover 91
5.1 B0-105Main Rotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
5.1.1 B0-105 RotorMesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
5.1.2 Test Conditionsand Computations . . . . . . . . . . . . . . . . . . . . . . 93
5.1.3 Results andDiscussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
EstimationofTransitionOnset . . . . . . . . . . . . . . . . . . . . . . . . 94
Integrated BladeLoads . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
5.2 S-76 MainRotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
5.2.1 S-76 RotorMesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
5.2.2 Test Conditionsand Computations . . . . . . . . . . . . . . . . . . . . . . 104
5.2.3 Swept-Taper Tip(Blade-TipMach Numberof0.65) . . . . . . . . . . . . 106
Mesh Convergence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Integrated BladeLoads . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Sectional BladeLoads . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Surface PressurePredictions . . . . . . . . . . . . . . . . . . . . . . . . . 110
Trajectory and SizeoftheTipVortex . . . . . . . . . . . . . . . . . . . . 112
5.2.4 Swept-Taper Tip(Blade-TipMach Numbersof0.60and 0.55) . . . . . . . 118
5.2.5 Rectangular Tip(Blade-Tip Mach Numbersof0.65and 0.6) . . . . . . . . 118
5.2.6 Anhedral Tip(Blade-TipMach Numbersof0.65and 0.60) . . . . . . . . . 121
5.2.7 Effect oftheTipShape . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
5.2.8 HoveringEndurance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
5.2.9 AeroacousticStudy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
5.3 Full-ScaleS-76 RotorBlade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
5.3.1 AeroelasticAnalysisoftheS-76 Rotor . . . . . . . . . . . . . . . . . . . 128
Structural Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
AnalysisofElasticBladeResults . . . . . . . . . . . . . . . . . . . . . . 131
5.3.2 ComparisonBetween Fulland Model-ScaleRotors . . . . . . . . . . . . . 132
5.3.3 TipVortexTrajectory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
5.3.4 AeroacousticStudy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
5.4 PSP MainRotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
5.4.1 PSP RotorMesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
5.4.2 Test Conditionsand Computations . . . . . . . . . . . . . . . . . . . . . . 138
5.4.3 Blade-Tip Mach Numberof0.585 . . . . . . . . . . . . . . . . . . . . . . 141
Integrated BladeLoads . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
viii