Open water performance of B-Series marine propellers in tandem configurations

In this study, the open water performance of three propellers with diverse rake angles was investigated by computational fluid dynamics method. The objective of this study was to find out the influence of the rake angle on the performance of conventional screw propellers. For this purpose, first, the obtained results for three B-series propellers were validated against the empirical results and then by modifying the rake angle, different models were investigated by the same method. Flow characteristics were examined for the models and the evolvement of vortices on different planes around the propeller were compared. The results suggest that in case of conventional screw propellers with linear rake distribution, while the effect of the rake angle on the propeller efficiency is not significant, the augmentation of this parameter improves the propeller thrust, especially at high propeller loads, but at the same time, the required torque increases, which is not desirable for the propeller design process.

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Application Study of Cartesian Grid in Numerical Prediction of a Marine Propeller

Volume 2: CFD and VIV ◽

10.1115/omae2016-54522 ◽

2016 ◽

Author(s):

Lang Gu ◽

Chao Wang ◽

Jian Hu

Keyword(s):

Performance Prediction ◽

Vortex Structure ◽

Open Water ◽

Cartesian Grid ◽

Marine Propellers ◽

Cavitation Performance ◽

Vortex Merging ◽

Flow Field Characteristics ◽

Open Water Performance ◽

Thrust And Torque

Cartesian grid was used in open water performance prediction, cavitation performance prediction and flow field characteristics of a propeller to research the applicability of the Cartesian grid in the numerical simulations of marine propellers. The comparisons of calculated results with the previous research and experimental results verify the accuracy of calculations with the grid on the prediction of thrust and torque coefficient and the simulation of cavitation distribution, wake velocity distribution and the vortex structure trajectory. Meanwhile the propulsive performances of Cartesian grid are better than other types of grid with the similar number of nodes. And the turning point of crash performance under cavitation condition and the phenomenon of vortex merging with neighboring vortex structure are excellent agreement with experiments and references.

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Numerical Analysis of Blade Stress of Marine Propellers

Journal of Marine Science and Application ◽

10.1007/s11804-020-00161-3 ◽

2020 ◽

Vol 19 (3) ◽

pp. 436-443

Author(s):

Kai Yu ◽

Peikai Yan ◽

Jian Hu

Keyword(s):

Axial Strain ◽

Equivalent Stress ◽

Open Water ◽

Object A ◽

Marine Propellers ◽

Maximum Equivalent Stress ◽

Tip Position ◽

Stress And Deformation ◽

Open Water Performance ◽

Set Up

Abstract In this study, a series of numerical calculations are carried out in ANSYS Workbench based on the unidirectional fluid–solid coupling theory. Using the DTMB 4119 propeller as the research object, a numerical simulation is set up to analyze the open water performance of the propeller, and the equivalent stress distribution of the propeller acting in the flow field and the axial strain of the blade are analyzed. The results show that FLUENT calculations can provide accurate and reliable calculations of the hydrodynamic load for the propeller structure. The maximum equivalent stress was observed in the blade near the hub, and the tip position of the blade had the largest stress. With the increase in speed, the stress and deformation showed a decreasing trend.

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Optimization of RANS Solver Simulation Setup for Propeller Open Water Performance Prediction

Volume 2: CFD and VIV ◽

10.1115/omae2015-41954 ◽

2015 ◽

Author(s):

Mohammed Islam ◽

Fatima Jahra ◽

Michael Doucet

Keyword(s):

Domain Size ◽

Open Water ◽

Fractional Factorial ◽

Navier Stokes ◽

Calm Water ◽

Simulation Results ◽

Open Water Performance ◽

Thrust And Torque ◽

Simulation Time ◽

Fixed Pitch

Mesh and domain optimization strategies for a RANS solver to accurately estimate the open water propulsive characteristics of fixed pitch propellers are proposed based on examining the effect of different mesh and computation domain parameters. The optimized mesh and domain size parameters were selected using Design of Experiments (DoE) methods enabling simulations to be carried out in a limited memory environment, and in a timely manner; without compromising the accuracy of results. A Reynolds-Averaged Navier Stokes solver is used to predict the propulsive performance of a fixed pitch propeller. The predicted thrust and torque for the propeller were compared to the corresponding measurements. A total of six meshing parameters were selected that could affect the computational results of propeller open water performance. A two-level fractional factorial design was used to screen out parameters that do not significantly contribute to explaining the dependent parameters: namely simulation time, propeller thrust and propeller torque. A total of 32 simulations were carried out only to find out that the selected six meshing parameters were significant in defining the response parameters. Optimum values of each of the input parameters were obtained for the DOE technique and additional simulations were run with those parameters. The simulation results were validated using open water experimental results of the same propeller. It was found that with the optimized meshing arrangement, the propeller opens simulation time was reduced by at least a factor of 6 as compared to the generally popular meshing arrangement. Also, the accuracy of propulsive characteristics was improved by up to 50% as compared to published simulation results. The methodologies presented in this paper can be similarly applied to other simulations such as calm water ship resistance, ship propulsion to systematically derive the optimized meshing arrangement for simulations with minimal simulation time and maximum accuracy. This investigation was carried out using STAR-CCM+, a commercial CFD package; however the findings can be applied to any RANS solver.

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Open water performance comparison between hub-type and hubless rim driven thrusters based on CFD method

Ocean Engineering ◽

10.1016/j.oceaneng.2015.04.074 ◽

2015 ◽

Vol 103 ◽

pp. 55-63 ◽

Cited By ~ 20

Author(s):

Bao-wei Song ◽

You-jiang Wang ◽

Wen-long Tian

Keyword(s):

Open Water ◽

Performance Comparison ◽

Open Water Performance ◽

Cfd Method

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A REVIEW OF METHODS FOR HYDRO-ACOUSTIC ANALYSIS OF NON-CAVITATING MARINE PROPELLERS

The International Journal of Maritime Engineering ◽

10.5750/ijme.v161ia3.1092 ◽

2021 ◽

Vol 161 (A3) ◽

Author(s):

Abhishek Kumar Tewari ◽

R Vijayakumar

Keyword(s):

Marine Mammals ◽

Acoustic Analysis ◽

Open Water ◽

Acoustic Analogy ◽

Hydrodynamic Analysis ◽

Radiated Noise ◽

Acoustic Performance ◽

Marine Propellers ◽

Potential Contributor ◽

Ocean Environment

Underwater Radiated Noise (URN) emanating from surface and underwater marine platforms has become a significant concern for all the Nations in view of the global requirement to minimise the increasing adverse impact on marine mammals and fishes and maintain ecological balance in the ‘Silent’ ocean environment. Ambient noise level in the sea, in 10 to 300 Hz frequency band, has increased by 20 to 30 dB due to shipping (Wittekind, 2009). Marine propeller (in non- cavitating and cavitating regime) is a potential contributor to the ships noise and a lot of scientific research has been undertaken and considerable progress has been achieved in estimating the hydro-acoustic performance of marine propellers. In light of this, the scope of this paper is to review and critically examine the various methods used for estimating the hydro-acoustic performance of marine propellers, particularly in the non-cavitating regime, over the past many years. This review paper brings out the details, applicability, merits and demerits of various methods, extrapolation laws to obtain full scale results, scientific conclusion of all the know-how on this subject and the scope of further research as perceived by the authors. This paper also presents a numerical methodology to estimate the noise radiated by a DTMB 4119 model propeller in the non-cavitating regime in open water condition. The hydrodynamic analysis of the propeller was performed using commercial CFD software STARCCM+, closure was achieved using standard k-ε turbulence model and hydro-acoustic predictions have been performed using FWH acoustic analogy. The results compare very well with the published literature.

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An Investigation Into the Effect of Biofouling on Full-Scale Propeller Performance Using CFD

Volume 2: CFD and FSI ◽

10.1115/omae2019-95315 ◽

2019 ◽

Cited By ~ 1

Author(s):

Soonseok Song ◽

Yigit Kemal Demirel ◽

Mehmet Atlar

Keyword(s):

Open Water ◽

Full Scale ◽

Roughness Effect ◽

Thrust Coefficient ◽

Propulsion Performance ◽

Negative Effect ◽

Precise Prediction ◽

Torque Coefficient ◽

Open Water Performance ◽

Propeller Performance

Abstract The negative effect of biofouling on ship resistance has been investigated since the early days of naval architecture. However, for more precise prediction of fuel consumption of ships, understanding the effect of biofouling on ship propulsion performance is also important. In this study, CFD simulations for the full-scale performance of KP505 propeller in open water, including the presence of marine biofouling, were conducted. To predict the effect of barnacle fouling on the propeller performance, experimentally obtained roughness functions of barnacle fouling were employed in the wall-function of the CFD software. The roughness effect of barnacles of varying sizes and coverages on the propeller open water performance was predicted for advance coefficients ranging from 0.2 to 0.8. From the simulations, drastic effects of barnacle fouling on the propeller open water performance were found. The result suggests that the thrust coefficient decreases while the torque coefficient increases with increasing level of surface fouling, which leads to a reduction of the open water efficiency of the propeller. Further investigations into the roughness effect on the pressure and velocity field, surface pressure and wall shear stress, and propeller vortices were examined.

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