Design of ducted propeller nozzles through a RANSE-based optimization approach

Abstract Marine propellers design requirements are always more pressing and the application of unusual propulsive configurations, like ducted propellers with decelerating nozzles, may represent a valuable alternative to fulfill stringent design constraints. Accelerating duct configurations were realized mainly to increase the propeller efficiency in the case of highly-loaded functioning. The use of decelerating nozzles sustains the postponing of the cavitating phenomena that, in turn, reflects into a reduction of vibrations and radiated noise. The design of decelerating nozzle, unfortunately, is still challenging. The complex interaction between the propeller and the nozzle, both in terms of global flow feature and local (tip located) phenomena, is not yet fully understood. No extensive systematic series, as in the case of accelerating configurations, are available and the design still relies on few measurements and data. On the other hand, viscous flow solvers appear as reliable and accurate tools for the prediction of complex flow fields and their application for the calculation of ducted propeller performance and nozzle flow was almost successful. Hence, using CFD as a part of a design procedure based on optimization, by combining a parametric description of the geometry, a RANSE solver (OpenFOAM) and a genetic type algorithm (the modeFrontier optimization environment), is the obvious step towards an even more reliable ducted propeller design. An actuator disk model is adopted to include efficiently the influence of the propeller on the flow around the duct; this allows avoiding the weighting of the computational effort that is necessary for the calculations of the thousands of geometries needed for the indirect design by optimization. Design improvements, in model scale, are measured by comparing, by means of dedicated fully resolved RANSE calculations, the performance of the optimized geometries with those of conventional shapes available in literature. For both nozzle typologies, dedicated shapes reducing the risk of cavitation and increasing the delivered thrust are obtained, showing the opportunity of customized nozzle design out of usual systematic series. In addition, by analyzing the results of the optimization histories, appropriate design criteria are derived for both accelerating and decelerating nozzle shapes.

[1]  Cesare Mario Rizzo,et al.  EFD and CFD Design and Analysis of a Propeller in Decelerating Duct , 2012 .

[2]  Diego Villa,et al.  Efficient and multi-objective cavitating propeller optimization: An application to a high-speed craft , 2017 .

[3]  J. D. van Manen.  Open-water test series with propellers in nozzles1 , 1954 .

[4]  R. Quereda,et al.  Combination of Pod, CLT and CRP Propulsion for Improving Ship Efficiency: The TRIPOD project , 2013 .

[5]  Justin E. Kerwin,et al.  Analysis of multi-component ducted propulsors in unsteady flow , 1993 .

[6]  S. Gaggero,et al.  An extensive analysis of numerical ship self-propulsion prediction via a coupled BEM/RANS approach , 2017 .

[7]  Diego Villa,et al.  Steady cavitating propeller performance by using OpenFOAM, StarCCM+and a boundary element method , 2017 .

[8]  Stefano Gaggero,et al.  Design and analysis of a new generation of CLT propellers , 2016 .

[9]  Sverre Steen,et al.  A CFD-based Scaling Approach for Ducted Propellers , 2016 .

[10]  Stefano Gaggero,et al.  A FRAMEWORK FOR THE DESIGN BY OPTIMIZATION OF HYDROFOILS UNDER CAVITATING CONDITIONS , 2016 .

[11]  Sverre Steen,et al.  Scale Effects on Open Water Characteristics of a Controllable Pitch Propeller Working within Different Duct Designs , 2016 .

[12]  Massimo Cardone,et al.  Ducted propeller flow analysis by means of a generalized actuator disk model , 2014 .

[13]  M. Hoekstra,et al.  A RANS-based analysis tool for ducted propeller systems in open water condition , 2006 .

[14]  Massimo Cardone,et al.  Performance analysis of ducted marine propellers. Part I – Decelerating duct , 2016 .

[15]  J. D. van Manen,et al.  The design of screw-propellers in nozzles1 , 1959 .

[16]  S. Goldstein.  On the Vortex Theory of Screw Propellers , 1929 .

[17]  Stefano Gaggero,et al.  Design of contracted and tip loaded propellers by using boundary element methods and optimization algorithms , 2016 .

[18]  Fahri Çelik.  Investigation of the Optimum Duct Geometry for A Passenger Ferry , 2011 .

[19]  S. Gaggero,et al.  Design, analysis and experimental characterization of a propeller in decelerating duct , 2013 .

[20]  Antonio Sanchez Caja,et al.  Simulation of the Incompressible Viscous Flow around Ducted Propellers with Rudders Using a RANSE Solver , 2008 .

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

[22]  Hrvoje Jasak,et al.  A tensorial approach to computational continuum mechanics using object-oriented techniques , 1998 .

[23]  M. Oosterveld.  Wake adapted ducted propellers , 1970 .

[24]  Giuliano Vernengo,et al.  Physics-Based Design by Optimization of Unconventional Supercavitating Hydrofoils , 2016 .

[25]  Johan Bosschers,et al.  Open-Water Thrust and Torque Predictions of a Ducted Propeller System with a Panel Method , 2012 .

[26]  P. Roache.  Perspective: A Method for Uniform Reporting of Grid Refinement Studies , 1994 .

[27]  J. D. van Manen,et al.  Effect of Radial Load Distribution on the Performance of Shrouded Propellers , 1962 .

[28]  Moustafa Abdel-Maksoud,et al.  Numerical analysis of ducted propeller performance under open water test condition , 2013 .

[29]  J. D. van Manen.  Recent research on propellers in nozzles1 , 1957 .

[30]  L Stipa,et al.  Experiments With Intubed Propellers , 1932 .