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Showing 1 to 20 of 49 for “"Vortex-lattice Method"”.
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Winglet Performance Evaluation through the Vortex Lattice Method
… Falcon 10 small size business jet using the vortex lattice method solver program SURFACES© by GreatOWL Publishing. The winglet geometric parameters investigated were the winglet span, cant angle, sweep and taper ratio in terms of their influence on drag, range, fuel burn, as well as wing root …
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A vortex-lattice method for Delta wing aerodynamics
… The lifting surface is modelled as a bound vortex sheet, while the wake is modelled as a force-free vortex sheet. The solution is obtained by the use of a unsteady Vortex-Lattice Method which includes the effect of leading edge separation. Numerical predictions for the aerodynamic loads and …
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Three dimensional flow analysis by the vortex-lattice method
A Vortex-Lattice Method (VLM) has been developed for the analysis of three-dimensional lifting bodies undergoing arbitrary motions. So far, the present method has been applied to thin surfaces in translational motion. Several cases were tested, such as rectangular, delta, sweptback and trapezoidal …
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A systematic investigation of the parameters affecting the accuracy of the vortex-lattice method
… the parameters affecting the accuracy of the vortex-lattice method when applied to a nonlinear lifting surface problem with leading edge separation. Among the factors investigated are the extensions of the bound vortex segments off the sharp edges of the wing, modifications of the Biot-Savart …
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Application of the vortex-lattice concept to flows with smooth- surface separation
A nonlinear three-dimensional vortex-lattice method which treats the steady separated flow over prolate bodies with open separation moving through an inviscid incompressible fluid is developed. The strength and position of the body wake are found as part of the solution. Specifically, flows with …
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A numerical model of unsteady, subsonic aeroelastic behavior
A method for predicting unsteady, subsonic aeroelastic responses has been developed. The technique accounts for aerodynamic nonlinearities associated with angles of attack, vortex-dominated flow, static deformations, and unsteady behavior. The angle of attack is limited only by the occurrence of …
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Numerical simulations of subsonic aeroelastic behavior and flutter suppression by active control
A method for predicting the unsteady, subsonic, aeroservoelastic response of a wing has been developed. The air, wing, and control surface are considered to be a single dynamical system. All equations are solved simultaneously in the time domain by a predictor-corrector method. The scheme allows …
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A Study of the Design of Adaptive Camber Winglets
… using a combination of three-dimensional vortex lattice method and two-dimensional panel method to obtain aerodynamic forces for the entire wing, based on different winglet camber configurations. This method was validated against high-fidelity steady Reynolds Averaged Navier-Stokes …
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Numerical simulation of unsteady rotor/stator interaction and application to propeller/rudder combination
… a numerical approach based on a potential flow method has been developed in order to simulate unsteady rotor/stator interaction, and to predict the unsteady performance of a propeller and its rudder. The method is first developed and tested in two-dimensions by using a boundary element method in …
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Numerical simulations of wings in unsteady flows
The unsteady vortex-lattice method is used to calculate the pressure coefficients on thick and thin airfoils in steady and unsteady flowfields. The parameters which affect the results, such as time step and aspect ratio, are studied. The effects of Reynolds number and thickness of a wing in steady …
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Verification, Validation and Application of Shear Stress Transport Transitional Model to a R/C Aircraft
… examined and compared to results obtained from a vortex-lattice method based approach.</p>
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A numerical study of the effects of leading edge vortex flaps on the performance of a 75° delta wing
Using a general, unsteady, nonlinear vortex lattice method, the aerodynamic loads have been found on a 75° delta wing with and without leading edge vortex flaps. The flap had an area approximately 26 percent of the wing area with a constant chord of 6.7 percent of the wing mean aerodynamic chord …
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Nonlinear steady and unsteady aerodynamics of wings and wing-body-combinations
A modified vortex lattice method is developed to solve for the nonlinear three-dimensional unsteady incompressible flow over delta wings. Symmetric motions (pitching, heaving) and asymmetric motions (roll, yaw) are considered. Then the method is generalized to treat the nonlinear three-dimensional …
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Novel Airframe Design for the Dual-Aircraft Atmospheric Platform Flight Concept
… airfoil for the unique application. Vortex-Lattice method tools were used to investigate the sensitivity of three-dimensional design parameters upon overall vehicle aerodynamic performance and determine both static and dynamic stability characteristics of the airframe. Performance …
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Control authority assessment in aircraft conceptual design
… the conceptual design phase. In this thesis, a methodology for rapid control power evaluation of preliminary design configurations against requirements at the key flight conditions is established. First, a collection of critical flight conditions to be considered using this methodology is …
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Separation and wakes over three-dimensional bodies
… of three-dimensional separation. The Vortex-Lattice method was employed to calculate the inviscid flow and the development of separated vortex sheets over a prolate spheroid. An approximate-method based on the assumption of local similarity was used to solve the boundary layer …
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Flight Dynamics and Maneuver Loads on a Commercial Aircraft with Discrete Source Damage
… that complicate the modeling. An extended vortex lattice code is used to model the quasi-steady aerodynamic forces. The vortex lattice method provides the force distribution which is not available elsewhere. Snapshots from the vortex lattice model are used to generate a reduced order model …
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Investigating Aerodynamic Coefficients and Stability Derivatives for Truss-Braced Wing Aircraft Using OpenVSP
… derivatives are investigated by applying Vortex-Lattice Method using OpenVSP, an open-source platform. The variation in aerodynamic parameters with changes in configurations and flow conditions are discussed as well. OpenVSP allows for study of these results with low computational expense. …
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Aeroelastic Analysis of Membrane Wings
… and plunge are simulated using a 3-D, free wake, vortex lattice method (VLM), and structural characteristics of the wing are simulated as a membrane supported by a rigid frame. The aerodynamics is validated by comparing the results from the VLM model for constant angle of attack flight, pitching …
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