Experimental study on hydrodynamics of L-type podded propulsor in straight-ahead motion and off-design conditions

Abstract

Experimental tests were conducted to evaluate the hydrodynamic performance of an L-type podded propulsor in straight-ahead motion and off-design conditions using an open-water measuring instrument developed by the authors for podded propulsors, a ship model towing tank, and under water particle image velocimetry (PIV) measurement systems. Under the three types of conditions, the main parameters of an L-type podded propulsor were measured, including the propeller thrust and torque, as well as the thrust, side force, and moment of the whole pod unit. In addition, the flow field on the section between the propeller and the strut was analyzed. Experimental results demonstrate that the dynamic azimuthing rate and direction and the turning direction affect the forces on the propeller and the whole pod unit. Forces are asymmetrically distributed between the left and right azimuthing directions because of the effect of propeller rotation. The findings of this study provide a foundation for further research on L-type podded propulsors.

Keywords

L-type podded propulsor / off-design condition / flow field / particle image velocimetry / propeller / hydrodynamic / experimental test

References

[1] Cheng BH, Dean JS, Miller RW, Cave WL. Hydrodynamic evaluation of hull forms with pod propulsors. Naval Engineering Journal, 1989, 101: 197-206

[2] Chicherin IA, Lobatchev MP, Pustoshny AV, Sanchez CA. On a propulsion prediction procedure for ships with podded propulsors using RANS-code analysis. 1st International Conference on Technological Advances in Podded Propulsion, 2004, 223-236

[3] Han JM, Paik KJ, Choi SH, Song IH, Shin SC. Prediction of steady performance of podded propellers. Proceedings of Annual Spring Meeting of SNAK, 2000, 144-147

[4] He W, Chen KQ, Li ZR. Experimental research on hydrodynamics of tandem type podded propulsors in azimuthing conditions. Journal of Huazhong University of Science and Technology Sci. Tech. (Nat. Sci. Ed.), 43, 2015, 01: 107-111

[5] Islam MF, Akinturk A, Veitch B, Liu P. Performance characteristics of static and dynamic azimuthing podded propulsor, 2009, 482-492

[6] Islam MF, Veitch B, Liu PF. Experimental Research on Marine Podded Propulsors. Journal of Naval Architecture and Marine Engineering, 2007, 4(2): 57-71

[7] ITTC -Recommended Procedures, 2002. Propulsion Performance -Podded Propeller Tests and Extrapolation 7.5-02-03-01.3, Revision 00.

[8] Kawakita C, Hoshino T, Minamiura J. Prediction of hydrodynamic performance of hydrofoil, strut and pod configuration by a surface panel method. The Japan Society of Naval Architects and Ocean Engineer, 1994, 87: 15-25

[9] Ohashi K, Hino T. Numerical simulations of flows around a ship with podded propulsor. 1st International Conference on Technological Advances in Podded Propulsion, 2004, UK: Newcastle University, 211-221

[10] Palm M, Jurgens D, Bendl D. Boundary layer control of twin skeg hull form with reaction podded propulsion, 2011, Hamburg, Germany: 2nd International Symposium on Marine Propulsors

[11] Reichel M. Manoeuvring forces on azimuthing podded propulsor model. Polish Maritime Research, 2007, 14: 3-8

[12] Sasaki N. The specialist committee on azimuthing podded propulsion–report and recommendations, 2008

[13] Shi YM, Zhang WB, Chen G. Hydrodynamic performance study of POD on single screw commercial vessel. Shipbuilding of China, 2010, 51: 36-44

[14] Szantyr JA. A surface panel method for hydrodynamic analysis of pod propulsors. Faculty of Ocean Engineering and Ship Technology, 2001, 12: 209-228