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Showing 1 to 20 of 22 for “"lifting line theory"”.
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Propeller performance analysis using lifting line theory
… in producing the open water diagram is to use lifting line theory to characterize the propeller blades. The bound circulation on the lifting line is a function of the blade geometry along with the blade velocity (both rotational and axial). Lerbs provided a method to evaluate the circulation …
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Numerically-based ducted propeller design using vortex lattice lifting line theory
This thesis used vortex lattice lifting line theory to model an axisymmetrical-ducted propeller with no gap between the duct and the propeller. The theory required to model the duct and its interaction with the propeller were discussed and implemented in Open-source Propeller Design and Analysis …
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An enhanced propeller design program based on propeller vortex lattice lifting line theory
… capability. The MIT Propeller Vortex Lattice Lifting Line Program (PVL) is an executable file written in FORTRAN language and serves as a preliminary propeller design tool. In this thesis, PVL was rewritten in MATLAB® and presented with the GUIs. The enhancements were incorporated in a revised …
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Preliminary design tools in turbomachinery: Non-uniformly spaced blade rows, multistage interaction, unsteady radial waves, and propeller horizontal-axis turbine optimization
… vane; and 4) a semi-analytical model based Lifting line theory for unified propeller and horizontal-axis turbine optimization. Each model has been thoroughly validated with existing models.</p> <p>With these models, non-uniformly spaced blade rows and vane clocking are investigated in detail …
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Integrated multi-disciplinary design of a sailplane wing
… and payoffs of integrated aircraft design. Lifting line theory and beam theory are used for the analysis of the aerodynamics and the structures of a composite sailplane wing. The wing is described by 33 - 34 design variables which involve the planform geometry, the twist distribution, and …
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Design of a Low Reynolds Number Propulsion System for an Autonomous Underwater Vehicle
… loss lift distribution for the propeller via lifting line theory, efficient airfoil sections for the propeller via a coupled viscous-inviscid flow solver and optimization, brushless DC motor identification via ideal motor theory and total system efficiency estimates. The coupled …
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Design and cavitation performance of contra-rotating propellers
… two methods for designing CRP in the context of lifting-line theory, along with a procedure for predicting the cavitation performance of conventional propellers and CRP. All of the above methods have been implemented numerically and integrated into a computer program developed in MATLAB®. …
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Boundary Layer Characteristics on a Tiltrotor Blade Model
… local effective angle of attack is obtained by lifting line theory, the results can be used in the trailing edge noise prediction code.
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Development of a Miniature VTOL Tail-Sitter Unmanned Aerial Vehicle
… analysis employed a propeller blade-element theory coupled with momentum equations to predict the influence of a propeller slipstream on the freestream flow field, then the aircraft was analyzed using 3-D vortex lifting-line theory to model finite wings immersed in the flow field. Four …
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Propeller design optimization for tunnel bow thrusters in the bollard pull condition
… OpenProp, a propeller design code based on lifting line theory, is a numerical model capable of design and analysis of such propellers. It has been experimentally validated for standard design conditions in an external flow, but until now has been incapable of design with no external fluid …
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Hydrofoil shape optimization by gradient methods
… optimization of hydrofoil sections and lifting surfaces advancing under a free surface. A mathematical model was developed based on the extension of a two-dimensional potential flow solution to account for three dimensional effects. Prandtl's lifting line theory was used to account for …
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Aeroelastic Analysis of Rotor Blades Using Three Dimensional Flexible Multibody Dynamic Analysis
… based on the first order shear deformable theory, has been developed specifically for folded plate and shell structures. The plate element does not suffer from either shear or aspect-ratio locking under transverse and membrane bending, respectively. A stiffened plate element has been …
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Laminar, steady and unsteady flow over inclined plates in two and three dimensions
The problem studied is the laminar flow over inclined, finite flat plates for moderately high Reynolds numbers in two and three dimensions. There are only few prior analyses, mainly for two dimensional flow, for this problem, and thus it was decided that it was worthwhile to study it now in great …
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Shape and Structural Optimization of Flapping Wings
… An assumed inflow model is derived based on lifting-line theory and is used to better approximate the effects of the induced drag on the wing. A multi-objective optimization approach is used since more than one aspect is considered in flapping wing design. The the epsilon-constraint approach …
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A dynamic model for aircraft poststall departure
… The aerodynamics are computed via a nonlinear lifting line theory with unsteady wake effects due to a discrete, nonplanar vortex system. A fully configured aircraft (main wing, horizontal tail and vertical fin) is mathematically constructed by modeling all lifting surfaces with bound, …
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Aspect ratio effects on wings at low Reynolds numbers
… with reasonable accuracy using Prandtl's lifting line theory. In addition to the change in lift slope the zero lift angle of attack was also influenced by the aspect ratio. Through flow visualization it was ascertained that the wingtips have a rather restricted effect on the laminar …
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An impulse framework for hydrodynamic force analysis : fish propulsion, water entry of spheres, and marine propellers
… presented; this code suite is based on propeller lifting line theory, which is shown to be a special case of the general impulse framework of this thesis. A marine propeller is designed, built, and tested over a range of off-design operating conditions. Experimental results match the predicted …
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Numerical Investigation of the Wake of a Rectangular Wing
Wakes of lifting bodies contain vortex sheets that roll up into strong streamwise vortices. The long time behavior of such vortices depends on the turbulence in the wake and the stability characteristics of the vortices themselves. In the near wake of a rectangular wing the flow field consists of a …
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A Numerical Vortex Approach To Aerodynamic Modeling of SUAV/VTOL Aircraft
… The wing aerodynamic model employs a numerical lifting-line method utilizing the 3D vortex lifting law along with known 2D airfoil data to predict the lift distribution across a wing for a prescribed upstream flowfield. The propeller/slipstream model uses blade element theory combined with …
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Multi-fidelity analysis and reduced-order modeling of wing-body aerodynamics
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2024-03-01 without embargo terms
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