Thruster and Hull Interaction

A hybrid method which couples a Vortex-Lattice Method (VLM) solver and a Reynolds-Averaged Navier-Stokes (RANS) solver is applied to simulate the interaction between a Dynamic Positioning (DP) thruster and an FPSO hull. The hybrid method could significantly reduce the number of cells to fifth of that in a full blown RANS simulation and thus greatly enhance the computational efficiency. The numerical results are first validated with available experimental data, and then used to assess the significance of the thruster/hull interaction in DP systems.

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A Prescribed-Wake Vortex Lattice Method for Preliminary Design of Co-Axial, Dual-Rotor Wind Turbines

Journal of Solar Energy Engineering ◽

10.1115/1.4034350 ◽

2016 ◽

Vol 138 (6) ◽

Cited By ~ 5

Author(s):

Aaron Rosenberg ◽

Anupam Sharma

Keyword(s):

Wind Turbines ◽

Vortex Lattice ◽

Navier Stokes ◽

Wake Vortex ◽

Preliminary Design ◽

Lattice Method ◽

Vortex Lattice Method ◽

Trailing Vortices ◽

Computational Fluid Dynamics Cfd ◽

Reynolds Averaged Navier Stokes

This paper extends the prescribed-wake vortex lattice method (VLM) to perform aerodynamic analysis of dual-rotor wind turbines (DRWTs). A DRWT turbine consists of a large, primary rotor placed co-axially behind a smaller, secondary rotor. The additional vortex system introduced by the secondary rotor of a DRWT is modeled while taking into account the singularities that can occur when the trailing vortices from the secondary (upstream) rotor interact with the bound vortices of the main (downstream) rotor. Pseudo-steady assumption is invoked, and averaging over multiple relative rotor positions is performed to account for the primary and secondary rotors operating at different rotational velocities. The VLM solver is first validated against experiments and blade element momentum theory results for a conventional, single-rotor turbine. The solver is then verified for two DRWT designs against results from two computational fluid dynamics (CFD) methods: (1) Reynolds-averaged Navier–Stokes CFD with an actuator disk representation of the turbine rotors and (2) large-eddy simulations with an actuator line model. Radial distributions of sectional torque force and angle of attack show reasonable agreement between the three methods. Results of parametric sweeps performed using VLM agree qualitatively with the Reynolds-averaged Navier–Stokes (RANS) CFD results demonstrating that the proposed VLM can be used to guide preliminary design of DRWTs.

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3D Simulation of a Convergent-Divergent Aero Engine Intake, Using Two Different CFD Methods

Volume 1: Turbo Expo 2005 ◽

10.1115/gt2005-68526 ◽

2005 ◽

Author(s):

Ioannis Templalexis ◽

Pericles Pilidis ◽

Geoffrey Guindeuil ◽

Theodoros Lekas ◽

Vassilios Pachidis

Keyword(s):

Vortex Lattice ◽

Cfd Simulation ◽

Three Dimensional ◽

Internal Flow ◽

Navier Stokes ◽

Lattice Method ◽

Vortex Lattice Method ◽

Aero Engine ◽

Flow Effects ◽

Development And Validation

This study refers to the development and validation of a Three Dimensional (3D) Vortex Lattice Method (VLM) to be used for internal flow case studies and more precisely aero-engine intake simulation. It examines the quantitative and qualitative response of the method to a convergent – divergent intake, produced as a surface of revolution of the CFM56-5B2 upper lip geometry. The study was carried out for three different sections namely: Intake outlet, intake throat and intake inlet. Moreover five different settings of Angle Of Attack (AOA) were considered. The VLM was based on an existing code. It was modified to accommodate internal flow effects and match, as closely as possible, the boundary conditions set by the Reynolds Average Navier-Stokes (RANS) Computational Fluid Dynamics (CFD) simulation. In the context of this study, Vortex Lattice-derived average values velocity profiles were compared against RANS CFD results.

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Aerodynamic model of propeller–wing interaction for distributed propeller aircraft concept

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410019857300 ◽

2019 ◽

Vol 234 (10) ◽

pp. 1688-1705 ◽

Cited By ~ 1

Author(s):

Baizura Bohari ◽

Quentin Borlon ◽

Murat Bronz ◽

Emmanuel Benard

Keyword(s):

Experimental Data ◽

Vortex Lattice ◽

Numerical Models ◽

Aircraft Design ◽

Computational Time ◽

Nonlinear Prediction ◽

Lattice Method ◽

Vortex Lattice Method ◽

Blade Element Theory ◽

Aerodynamic Model

The present investigation addresses two key issues in aerodynamic performance of a propeller–wing configuration, namely linear and nonlinear predictions with low-order numerical models. The developed aerodynamic model is targeted to be used in the preliminary aircraft design loop. First, the combination of selected propeller model, i.e. blade element theory with the wing model, i.e. lifting line theory and vortex lattice method is considered for linear aerodynamic model. Second, for the nonlinear prediction, a modified vortex lattice method is paired with the two-dimensional viscous effect of the airfoils to simplify and reduce the computational time. These models are implemented and validated with existing experimental data to predict the differences in lift and drag distribution. Overall, the predicted results show agreement with low percentage of error compared with the experimental data for various thrust coefficients and produced induced drag distribution that behaves as expected.

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A Hybrid Viscous/Potential Flow Method for the Prediction of the Wetted and Cavitating Performance of Ducted Propellers

10.5957/fast-2015-007 ◽

2015 ◽

Author(s):

Spyros A. Kinnas ◽

Chan-Hoo Jeon ◽

Ye Tian

Keyword(s):

Present Method ◽

Vortex Lattice ◽

Navier Stokes ◽

Propeller Blade ◽

Lattice Method ◽

Viscous Potential Flow ◽

Vortex Lattice Method ◽

Hybrid Numerical Method ◽

Effective Wake ◽

Ducted Propellers

This paper presents the analysis of the performance for various ducted propellers using a hybrid numerical method, which couples a vortex lattice method (VLM) for the analysis of propellers and a Reynolds-Averaged Navier-Stokes solver for the prediction of the viscous fluid flow around the duct. The effects of viscosity on the effective wake and on the performance of the propeller blade, as well as on the predicted duct forces, are assessed. The prediction of the performance for those ducted propellers from the present method is validated against existing experimental data.

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A Hybrid Viscous/Potential Flow Method for the Prediction of the Wetted and Cavitating Performance of Ducted Propellers

10.5957/pss-2012-005 ◽

2012 ◽

Author(s):

Spyros A. Kinnas ◽

Chan-Hoo Jeon ◽

Ye Tian

Keyword(s):

Present Method ◽

Vortex Lattice ◽

Navier Stokes ◽

Propeller Blade ◽

Lattice Method ◽

Viscous Potential Flow ◽

Vortex Lattice Method ◽

Hybrid Numerical Method ◽

Effective Wake ◽

Ducted Propellers

This paper presents the analysis of the performance for various ducted propellers using a hybrid numerical method, which couples a vortex lattice method (VLM) for the analysis of propellers and a Reynolds-Averaged Navier-Stokes solver for the prediction of the viscous fluid flow around the duct. The effects of viscosity on the effective wake and on the performance of the propeller blade, as well as on the predicted duct forces, are assessed. The prediction of the performance for those ducted propellers from the present method is validated against existing experimental data.

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Generalized vortex lattice method for planar supersonic flow

AIAA Journal ◽

10.2514/3.13655 ◽

1997 ◽

Vol 35 ◽

pp. 1230-1233

Author(s):

Paulo A. O. Soviero ◽

Hugo B. Resende

Keyword(s):

Supersonic Flow ◽

Vortex Lattice ◽

Lattice Method ◽

Vortex Lattice Method

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Static Aeroelastic Characteristics of Morphing Trailing-Edge Wing Using Geometrically Exact Vortex Lattice Method

International Journal of Aerospace Engineering ◽

10.1155/2019/5847627 ◽

2019 ◽

Vol 2019 ◽

pp. 1-15

Author(s):

Sen Mao ◽

Changchuan Xie ◽

Lan Yang ◽

Chao Yang

Keyword(s):

Vortex Lattice ◽

Deflection Angle ◽

Aircraft Design ◽

Analysis Method ◽

Lattice Method ◽

Trailing Edge ◽

Vortex Lattice Method ◽

Analysis And Design ◽

Aeroelastic Analysis ◽

Typical Model

A morphing trailing-edge (TE) wing is an important morphing mode in aircraft design. In order to explore the static aeroelastic characteristics of a morphing TE wing, an efficient and feasible method for static aeroelastic analysis has been developed in this paper. A geometrically exact vortex lattice method (VLM) is applied to calculate the aerodynamic forces. Firstly, a typical model of a morphing TE wing is chosen and built which has an active morphing trailing edge driven by a piezoelectric patch. Then, the paper carries out the static aeroelastic analysis of the morphing TE wing and corresponding simulations were carried out. Finally, the analysis results are compared with those of a traditional wing with a rigid trailing edge using the traditional linearized VLM. The results indicate that the geometrically exact VLM can better describe the aerodynamic nonlinearity of a morphing TE wing in consideration of geometrical deformation in aeroelastic analysis. Moreover, out of consideration of the angle of attack, the deflection angle of the trailing edge, among others, the wing system does not show divergence but bifurcation. Consequently, the aeroelastic analysis method proposed in this paper is more applicable to the analysis and design of a morphing TE wing.

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