Solution of the flow over a non-uniform heavily loaded ducted actuator disk

Abstract The paper presents an extension to ducted rotors of the nonlinear actuator disk theory of Conway (J. Fluid Mech., vol. 365, 1998, pp. 235–267) and it is exact for incompressible, axisymmetric and inviscid flows. The solution for the velocities and the Stokes stream function results from the superposition of ring vortices properly arranged along the duct surface and the wake region. Using a general analytical procedure the flow fields are given as a combination of one-dimensional integrals of expressions involving complete as well as incomplete elliptic integrals. The solution being exact, the proper shape of the slipstream whether converging or diverging is naturally accounted for, even for heavy loads. A semi-analytical method has been developed that enables the flow induced by an actuator disk housed in a contoured duct to be solved duly accounting for the nonlinear mutual interaction between the duct and the rotor. Non-uniform load distributions, rotor wake rotation and ducts of general shapes and thickness distribution can be dealt with. Thanks to its reduced numerical cost, the method is well suited for the design and/or analysis of ducted rotors for marine, wind and aeronautical applications.

[1]  O de Vries,et al.  Fluid dynamic aspects of wind energy conversion , 1979 .

[2]  G. Batchelor,et al.  An Introduction to Fluid Dynamics , 1968 .

[3]  R. Lewis,et al.  Vortex Element Methods for Fluid Dynamic Analysis of Engineering Systems , 1991 .

[4]  J. Baltazar,et al.  On the Modelling of the Flow in Ducted Propellers With a Panel Method , 2009 .

[5]  J. A. C. Falcão de Campos On the calculation of ducted propeller performance in axisymmetric flows , 1983 .

[6]  Michael D. Greenberg,et al.  Nonlinear actuator disk theory and flow field calculations, including nonuniform loading , 1970 .

[7]  J. Anderson,et al.  Fundamentals of Aerodynamics , 1984 .

[8]  商船學校 Marine propellers and propulsion , 1913 .

[9]  L. A. Van Gunsteren A contribution to the solution of some specific ship propulsion problems: A reappraisal of momentum theory , 1973 .

[10]  Jong Jae Lee,et al.  A SURFACE PANEL METHOD FOR THE HYDRODYNAMIC ANALYSIS OF DUCTED PROPELLERS , 1987 .

[11]  I. S. Gradshteyn,et al.  Table of Integrals, Series, and Products , 1976 .

[12]  Erich Martensen,et al.  Berechnung der Druckverteilung an gitterprofilen in ebener Potentialströmung mit einer fredholmschen integralgleichung , 1959 .

[13]  John T. Conway,et al.  Analytical solutions for the Newtonian gravitational field induced by matter within axisymmetric boundaries , 2000 .

[14]  Poul Andersen,et al.  Hydrodynamics of Ship Propellers , 1993 .

[15]  A. B. Basset,et al.  Treatise on Hydrodynamics , 1889, Nature.

[16]  J. Conway Analytical solutions for the actuator disk with variable radial distribution of load , 1995, Journal of Fluid Mechanics.

[17]  Richard G. J. Flay,et al.  Effect of placing a diffuser around a wind turbine , 2000 .

[18]  John P. Breslin,et al.  Hydrodynamics of Ship Propellers: Actuator disc theory , 1993 .

[19]  Harvey Chaplin A Method for Numerical Calculation of Slipstream Construction of a Shrouded Impulse Disc in the Static Case with Application to Other Axisymmetric Potential Flow Problems , 2010 .

[20]  John T. Conway,et al.  Exact actuator disk solutions for non-uniform heavy loading and slipstream contraction , 1998, Journal of Fluid Mechanics.

[21]  E J Glover,et al.  DUCTED PROPELLER DESIGN METHOD: A NEW APPROACH USING SURFACE VORTICITY DISTRIBUTION TECHNIQUES AND LIFTING LINE THEORY , 1972 .

[22]  N. Sonine,et al.  Recherches sur les fonctions cylindriques et le développement des fonctions continues en séries , 1880 .

[23]  Serkan Ekinci,et al.  An Approach to the Design of Ducted Propeller , 2010 .