Optimal matching investigation of marine contra-rotating propellers for energy consumption minimization

Hou, Lixun; Liang, Yin; Hu, Ankang; Chang, Xin; Lin, Yi; Wang, Shun

doi:10.1007/s00773-021-00809-x

Cited by 5 publications

(2 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To date, most studies on contra-rotating propellers are focused on the analysis of the global performance for improved efficiency and design, [1][2][3][4][5][6][7][8][9][10][11] while little is known about their wake features. While the latter are already especially complex in the case of propellers working alone, [12][13][14][15][16][17][18][19][20][21][22][23] the analysis of their physics becomes even more problematic, when two contra-rotating propellers work together.…”

Section: Introductionmentioning

confidence: 99%

Interaction between the helical vortices shed by contra-rotating propellers

Posa,

Capone,

Alves Pereira

et al. 2024

Physics of Fluids

View full text Add to dashboard Cite

Large eddy simulation is adopted to analyze the interaction between the tip vortices shed by two contra-rotating propellers, by using a computational grid consisting of 4.6 × 109 points. Despite the complexity of the wake topology, the results of the computations show an excellent agreement with the measurements from an earlier experimental study on the same system. The interaction between the tip vortices shed by the two propellers produces vortex rings. Each of them consists of six helical sides, which are connected by U-shaped vortex lobes. The three upstream lobes of each vortex ring move to outer radial coordinates, as a result of their shear with the downstream lobes of the upstream vortex ring. In contrast, the downstream U-shaped lobes move to inner radial coordinates, as a result of their shear with the upstream lobes of the downstream vortex ring. This interaction results in an overall expansion of the wake of the contra-rotating propellers. The regions of shear between the U-shaped lobes of consecutive vortex rings are the areas of the largest turbulent stresses, which achieve higher levels than those produced in the wake of the two front and rear propellers working alone. This complex flow physics also triggers a faster instability of the wake system, breaking its coherence at more upstream coordinates, in comparison with the isolated propellers.

show abstract

Section: Introductionmentioning

confidence: 99%

Interaction between the helical vortices shed by contra-rotating propellers

Posa,

Capone,

Alves Pereira

et al. 2024

Physics of Fluids

View full text Add to dashboard Cite

show abstract

“…As the most widely used propulsion system, the propeller is featured with high efficiency and lightweight. Many specific types of propellers have been developed for various working scenarios, such as ducted propellers (Villa et al , 2020), coaxial contra-rotating propellers (Hou et al , 2021) and tandem propellers (Liu and Gong, 2020). The ducted propeller will be investigated in detail in the present study.…”

Section: Introductionmentioning

confidence: 99%

Effect of ducts on the hydrodynamic performance of marine propellers

Liu

Gong

Bian

et al. 2021

View full text Add to dashboard Cite

PurposeHydrodynamic forces and efficiency of bare propeller and ducted propellers with a wide range of advance ratio (J) and attack angle (θ) are examined. The thrust and torque coefficients and the efficiency are presented and discussed in detail. The present results give a reliable guidance to the improvement of the hydrodynamic characteristics of ducted propellers.Design/methodology/approachThe effect of a duct on the hydrodynamic performance of the KP458 propeller is numerically investigated in this study. Finite volume method (FVM)-based simulations are performed for a wide range of advance ratio J (0 ≤ J ≤ 0.75) and attack angle θ of the duct (15° ≤ θ ≤ 45°). A cubic computational domain is employed in this study, and the moving reference frame (MRF) approach is adopted to handle the rotation of the propeller. Turbulence is accounted for with the RNG k-ε model. The present numerical results are first compared against available experimental data and a good agreement is achieved.FindingsThe simulation results demonstrate that the hydrodynamic forces and efficiency increases and decreases with J, respectively, at the same attack angle. In addition, it is demonstrated that the hydrodynamic forces and efficiency are both improved due to the presence of the duct, which eventually leads a better hydrodynamic performance at high advance ratios. It is further revealed that as the attack angle increases, the pressure difference between the suction- and pressure-surfaces of the propeller is also augmented, which results in a larger thrust. The wake field is more uniform at θ = 30°, suggesting that a higher efficiency can be obtained.Originality/valueThe present study aims to investigate the effect of a duct on the KP458 propeller subjected to uniform inbound flow. The relationship between the uniform incoming flow and the attack angle of the duct is mainly focused, and the design of the ducted propellers for any ship hull can be improved according to this relationship.

show abstract