Aeroelastic analysis and structural parametric design of composite rotor blade

Purpose The purpose of this study is to obtain optimum locations, peak deflection and chord of the twin trailing-edge flaps and optimum torsional stiffness of the helicopter rotor blade to minimize the vibration in the rotor hub with minimum requirement of flap control power. Design/methodology/approach Kriging metamodel with three-level five variable orthogonal array-based data points is used to decouple the optimization problem and actual aeroelastic analysis. Findings Some very good design solutions are obtained using this model. The best design point in minimizing vibration gives about 81 per cent reduction in the hub vibration with a penalization of increased flap power requirement, at normal cruise speed of rotor-craft flight. Practical implications One of the major challenges in the helicopters is the high vibration level in comparison with fixed wing aircraft. The reduction in vibration level in the helicopter improves passenger and crew comfort and reduces maintenance cost. Originality/value This paper presents design optimization of the helicopter rotor blade combining five design variables, such as the locations of twin trailing-edge flaps, peak deflection and flap chord and torsional stiffness of the rotor. Also, this study uses kriging metamodel to decouple the complex aeroelastic analysis and optimization problem.

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Consideration of structural constraints in passive rotor blade design for improved performance

The Aeronautical Journal ◽

10.1017/s0001924000011386 ◽

2015 ◽

Vol 119 (1222) ◽

pp. 1513-1539 ◽

Cited By ~ 1

Author(s):

J. W. Lim

Keyword(s):

Performance Improvement ◽

Rotor Blade ◽

Parametric Design ◽

Control Point ◽

Bending Moment ◽

Structural Constraints ◽

Design Variables ◽

Significant Performance ◽

Structural Redesign ◽

Improved Performance

AbstractThis design study applied parameterisation to rotor blade for improved performance. In the design, parametric equations were used to represent blade planform changes over the existing rotor blade model. Design variables included blade twist, sweep, dihedral, and radial control point. Updates to the blade structural properties with changes in the design variables allowed accurate evaluation of performance objectives and realistic structural constraints – blade stability, steady moments (flap bending, chord bending, and torsion), and the high g manoeuvring pitch link loads. Performance improvement was demonstrated with multiple parametric designs. Using a parametric design with advanced aerofoils, the predicted power reduction was 1·0% in hover, 10·0% at μ = 0·30, and 17·0% at μ = 0·40 relative to the baseline UH-60A rotor, but these were obtained with a 35% increase in the steady chord bending moment at μ = 0·30 and a 20% increase in the half peak-to-peak pitch link load during the UH-60A UTTAS manoeuvre Low vibration was maintained for this design. More rigorous design efforts, such as chord tapering and/or structural redesign of the blade cross section, would enlarge the feasible design space and likely provide significant performance improvement.

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Consideration of structural constraints in passive rotor blade design for improved performance

The Aeronautical Journal ◽

10.1017/aer.2016.77 ◽

2016 ◽

Vol 120 (1232) ◽

pp. 1604-1631 ◽

Cited By ~ 2

Author(s):

J.W. Lim

Keyword(s):

Performance Improvement ◽

Rotor Blade ◽

Parametric Design ◽

Control Point ◽

Bending Moment ◽

Structural Constraints ◽

Design Variables ◽

Significant Performance ◽

Structural Redesign ◽

Improved Performance

ABSTRACTThis design study applied parameterisation to rotor blade for improved performance. In the design, parametric equations were used to represent blade planform changes over the existing rotor blade model. Design variables included blade twist, sweep, dihedral and the radial control point. Updates to the blade structural properties with changes in the design variables allowed accurate evaluation of performance objectives and realistic structural constraints – blade stability, steady moments (flap bending, chord bending and torsion) and the high-g manoeuvre pitch link loads. Performance improvement was demonstrated with multiple parametric designs. Using a parametric design with advanced aerofoils, the predicted power reduction was 1.0% in hover, 10.0% at μ = 0.30 and 17.0% at μ = 0.40, relative to the baseline UH-60A rotor, but these were obtained with a 35% increase in the steady chord bending moment at μ = 0.30 and a 20% increase in the half peak-to-peak pitch link load during the UH-60A UTTAS manoeuvre. Low vibration was maintained for this design. More rigorous design efforts, such as chord tapering and/or structural redesign of the blade cross section, would enlarge the feasible design space and likely provide significant performance improvement.

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Analysis of Rotor Blade Aeroelastic Deformation Utilizing the Uncoupled Static Aeroelastic Analysis Method

10.2514/6.2022-2555 ◽

2022 ◽

Author(s):

Francis R. Phillips ◽

Trent D. White ◽

Allen Davis ◽

Darren J. Hartl

Keyword(s):

Rotor Blade ◽

Analysis Method ◽

Aeroelastic Analysis

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Performance improvement of helicopter rotors through blade redesigning

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-01-2018-0009 ◽

2019 ◽

Vol 91 (5) ◽

pp. 747-755

Author(s):

Wienczyslaw Stalewski ◽

Wieslaw Zalewski

Keyword(s):

Performance Improvement ◽

Rotor Blade ◽

Parametric Design ◽

Aerodynamic Characteristics ◽

Rotor Blades ◽

Helicopter Rotor ◽

Content Type ◽

Simplified Approach ◽

Helicopter Rotor Blades ◽

Blade Shape

Purpose The purpose of this paper is to determine dependencies between a rotor-blade shape and a rotor performance as well as to search for optimal shapes of blades dedicated for helicopter main and tail rotors. Design/methodology/approach The research is conducted based on computational methodology, using the parametric-design approach. The developed parametric model takes into account several typical blade-shape parameters. The rotor aerodynamic characteristics are evaluated using the unsteady Reynolds-averaged Navier–Stokes solver. Flow effects caused by rotating blades are modelled based on both simplified approach and truly 3D simulations. Findings The computational studies have shown that the helicopter-rotor performance may be significantly improved even through relatively simple aerodynamic redesigning of its blades. The research results confirm high potential of the developed methodology of rotor-blade optimisation. Developed families of helicopter-rotor-blade airfoils are competitive compared to the best airfoils cited in literature. The finally designed rotors, compared to the baselines, for the same driving power, are characterised by 5 and 32% higher thrust, in case of main and tail rotor, respectively. Practical implications The developed and implemented methodology of parametric design and optimisation of helicopter-rotor blades may be used in future studies on performance improvement of rotorcraft rotors. Some of presented results concern the redesigning of main and tail rotors of existing helicopters. These results may be used directly in modernisation processes of these helicopters. Originality/value The presented study is original in relation to the developed methodology of optimisation of helicopter-rotor blades, families of modern helicopter airfoils and innovative solutions in rotor-blade-design area.

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