The Experts below are selected from a list of 150 Experts worldwide ranked by ideXlab platform

Liu P - One of the best experts on this subject based on the ideXlab platform.

  • Experiments with Podded Propulsors in Static Azimuthing Conditions
    2015
    Co-Authors: Islam M. F, Akinturk A, Veitch B, Bose N., Liu P
    Abstract:

    Archives des publications du CNRC Experiments with Podded Propulsors in static azimuthing condition

  • Study of Podded Propulsors with varied bub angle and configurations
    2009
    Co-Authors: Islam M. F, Veitch B, Liu P, Akinturk A
    Abstract:

    This paper presents an experimental study on the effects of tapered hub on the propulsive characteristics of puller and pusher Podded Propulsors in straight course and static azimuthing conditions while operating in open water. The propulsive performance of two model pod units having the same pod-strut shape and propeller blade geometry with different hub shapes were measured using a custom designed pod dynamometer. The dynamometer system consisted of a six-component global dynamometer and a three-component pod dynamometer. The measurements consisted of the forces and moments of the units in the three co-ordinate directions and thrust and torque of the propellers for a range of advance coefficients from 0 to 1.2 combined with the range of static azimuthing angles from +30\ub0 to \u201330\ub0 in 15\ub0 increments in pusher and puller configurations. The variations in the propulsive performance due to the change in hub geometry in straight ahead conditions were examined first, followed by a study on the effects in different static azimuthing angles. Comparison of the results of the two pod units illustrated that in both pusher and puller configurations, the effect of hub taper angle is more significant at lower advance coefficients while the effects increased with increasing azimuthing angle.Peer reviewed: NoNRC publication: Ye

  • Propella: A numerical tool to study various aspects of Podded Propulsors
    2008
    Co-Authors: Islam M., Veitch B, Liu P
    Abstract:

    This paper describes the numerical aspects of a research program on Podded Propulsors, which is being undertaken jointly by the Ocean Engineering Research Centre at Memorial University of Newfoundland, the National Research Council's Institute for Ocean Technology, Oceanic Consulting Corporation, and Thordon Bearings Ltd. The numerical tool is an in-house panel method code, PROPELLA. The code is a low order source-doublet, steady/unsteady time domain panel method code having capabilities to predict hydrodynamic performance of screw propellers with various configurations. Under the research program, the code was extended and used to model the propellers, pod-strut combinations and strut-wake impingement model. Amongst the hydrodynamic issues that have been addressed through numerical predictions were questions regarding the effects of hub taper angle (propeller only case and pod-strut-propeller case), pod-strut configuration (push and pull), geometric variations, azimuthing conditions and pod-strut interactions (wake impingement effect) on Podded propeller performance. Predictions were made both in pusher and puller configurations for the pods and reasonable agreement was achieved between the predictions and measurements. The code is being modified to study the Podded Propulsors' performance at static and dynamic azimuthing conditions. The code is also capable of performing simulations with propellers and bodies like ship hull, underwater vehicles with fins.Peer reviewed: YesNRC publication: Ye

  • Gap effect on performance of Podded Propulsors in straight and static azimuthing conditions
    2007
    Co-Authors: Islam M., Akinturk A, Veitch B, Macneill A., Liu P
    Abstract:

    The paper presents preliminary results of an experimental study on the effect of gap distance on propulsive characteristics of puller Podded Propulsors in straight course and static azimuthing open water conditions. The gap distance is the axial distance between the rotating (propeller) and stationary (pod) part of a Podded propulsor. The propeller thrust and torque, unit forces and moments in the threecoordinate directions of a Podded unit were measured using a custom designed pod dynamometer in puller configurations with varied operating conditions. The model propulsor was tested at the gap distances of 0.3%, 1% and 2% of propeller diameter for a range of advance coefficients combined with the range of static azimuthing angles from +20\ub0 to ?20\ub0 in a 10\ub0 increment. The results show that the gap distance does not have significant effect on propeller torque in straight course conditions, but has effects in azimuthing conditions. The propeller thrust and efficiency were influenced by the change of gap distance and the effects were more obvious at high azimuthing angles and high advance coefficient values. The unit thrust and efficiency, transverse and vertical forces, as well as moments in three coordinate directions were not influenced by the gap distance, taking into account the uncertainty in the measurements, both in straight course and azimuthing conditions.NRC publication: Ye

  • Experiments with Podded Propulsors in static azimuthing conditions
    2007
    Co-Authors: Islam M., Akinturk A, Veitch B, Bose N., Liu P
    Abstract:

    The paper presents a comprehensive experimental study of the variations of propulsive characteristics of puller and pusher Podded Propulsors in static azimuthing open water conditions. A custom designed six-component global dynamometer and a three-component pod dynamometer were used to measure the propulsive performance of a Podded unit in pusher and puller configurations in a towing tank. The unit was tested to measure the forces on the whole unit in the three co-ordinate directions as well as thrust and torque of the propeller for a range of advance coefficients combined with the range of static azimuthing angles from +30\ub0 to ?30\ub0 with 5\ub0 and 10\ub0 increments. The variations in propulsive performance of the unit with change of azimuthing angle and advance speed in the two configurations were examined. The results of the measurements are presented as changes of forces and moments of the propulsor unit with advance coefficients and azimuthing angles. The results illustrate that the axial and side forces and the steering moment are complex functions of the azimuthing angles both for puller and pusher Propulsors.NRC publication: Ye

N Bose - One of the best experts on this subject based on the ideXlab platform.

  • performance study of Podded propulsor in static azimuthing conditions
    International shipbuilding progress, 2009
    Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian Veitch, N Bose
    Abstract:

    This paper presents a comprehensive experimental study on variations of propulsive characteristics of puller and pusher Podded Propulsors in static azimuthing open water conditions. A custom designed experimental apparatus consisting of a six-component global dynamometer and a three-component pod dynamometer was used to measure the propulsive performance of a model pod unit in pusher and puller configurations in a towing tank. The pod model was tested to measure the forces on the whole unit as well as thrust and torque of the propeller shaft for a range of advance coefficients combined with a range of static azimuth angles from +30° to −30°. The variations in forces and moments of the propulsor unit with change of azimuth angle and advance speed are presented in non-dimensional forms. The results illustrate that the propeller thrust and torque as well as the unit axial, side forces and the steering moment are complex functions of the azimuth angle and propeller loading.

  • ice loads acting on a model Podded propeller blade omae2005 67416
    Journal of Offshore Mechanics and Arctic Engineering-transactions of The Asme, 2007
    Co-Authors: Jungyong Wang, Ayhan Akinturk, Stephen J Jones, N Bose, Hohwan Chun
    Abstract:

    With the increase in popularity of Podded Propulsors and arctic navigation, understanding the interaction between a Podded propulsor and ice has become more important. Propeller-ice interaction itself is a complicated process with a high level of uncertainty resulting from the uncertainties associated with the properties of the ice and with the propeller-ice interaction conditions. Model tests provide relatively well-controlled ice properties and interaction conditions to reduce the uncertainties. In order to improve the understanding of this interaction and to develop numerical models of it, a model Podded propulsor was used in “Puller” mode, and ice loads were measured on its instrumented blade and propeller shaft. The results of the experiments conducted to simulate the interactions (milling) of the instrumented blade with ice in different operating conditions are reported in this paper. Loads measured during the milling consist of ice milling loads, “inseparable” hydrodynamic loads, and “separable” hydrodynamic loads. The sample results presented here include ice milling and inseparable hydrodynamic loads for various advance coefficients and depths of cut (amount of blade penetration into ice). Some results are compared with existing ice load models. DOI: 10.1115/1.2426993

Mohammed Islam - One of the best experts on this subject based on the ideXlab platform.

  • Performance study of Podded Propulsors with varied geometry and azimuthing conditions
    2009
    Co-Authors: Mohammed Islam
    Abstract:

    The current research investigates the performance of Podded Propulsors with varied geometry at different azimuthing conditions for pusher and puller configurations in open water. -- In order to determine the prominent geometric parameters and to establish their effects on the hydrodynamic performance, the first part of the research concentrated on the geometry of pusher- and puller-Podded Propulsors. This experimental study consisted of investigating five geometrical parameters and their effects on propeller thrust, torque and efficiency, unit thrust and efficiency of Podded Propulsors. The work used a factorial design (a design of experiment technique) and analysis approach to study these effects. -- The second part of the research focussed on the hydrodynamic properties of the Podded Propulsors in static and dynamic azimuthing conditions. This study implemented two investigations using two separate experimental apparatus. In the first investigation, two Podded Propulsors were tested to measure the forces and moments on the propeller and on the unit at different static azimuthing angles within the range of -30° to 30°. In the second investigation, a separate dynamometer system was used to measure forces and moments of a model pod unit at different static and dynamic azimuthing conditions within the range of 0° to 360°. An additional study evaluated the effects of azimuthing rate and propeller shaft speed on the performance parameters under consideration at dynamic azimuthing conditions. -- The study of pods with varied geometry showed that the geometric parameters have noticeable effect on propulsive characteristics of the propulsor. The analysis provided valuable information to the Podded propulsor designers. In static azimuthing conditions in the range of +30° to -30°, the propeller and unit performance coefficients changed with the change of propeller loading and azimuthing angles. In the dynamic azimuthing study, the coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. Further, these results can be used as a base for validation of numerical modelling. -- The uncertainty analysis of the measurements provided strong evidence that the presented results revealed the true performance characteristics of the model scale Podded Propulsors under consideration.

  • performance study of Podded propulsor in static azimuthing conditions
    International shipbuilding progress, 2009
    Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian Veitch, N Bose
    Abstract:

    This paper presents a comprehensive experimental study on variations of propulsive characteristics of puller and pusher Podded Propulsors in static azimuthing open water conditions. A custom designed experimental apparatus consisting of a six-component global dynamometer and a three-component pod dynamometer was used to measure the propulsive performance of a model pod unit in pusher and puller configurations in a towing tank. The pod model was tested to measure the forces on the whole unit as well as thrust and torque of the propeller shaft for a range of advance coefficients combined with a range of static azimuth angles from +30° to −30°. The variations in forces and moments of the propulsor unit with change of azimuth angle and advance speed are presented in non-dimensional forms. The results illustrate that the propeller thrust and torque as well as the unit axial, side forces and the steering moment are complex functions of the azimuth angle and propeller loading.

  • Effects of geometry variations on the performance of Podded Propulsors
    Transactions of the Society of Naval Architects and Marine Engineers, 2008
    Co-Authors: Mohammed Islam, Brian Veitch, Neil Bose, S Molloy, Pengfei Liu
    Abstract:

    This paper presents results and analyses of an experimental study into the effects of geometric parameters on the propulsive characteristics of puller and pusher Podded Propulsors in straight course open water conditions. Five geometric parameters were chosen for the current study and a design of experiment technique was used to design a series of 16 pods that combined the parameters. Tests on the 16 different pod-strut-propeller combinations in puller and pusher configurations were completed using a custom designed Podded propeller test rig. The dynamometry consisted of a six-component global dynamometer and a three-component pod dynamometer. The test rig was used to measure the thrust and torque of the propellers, and forces and moments on the whole unit in the three orthogonal directions. The design of experiment analysis technique was then used to identify the most significant geometric parameters and interaction of parameters that affect propeller thrust, torque and efficiency as well as unit thrust and efficiency in both the puller and pusher configurations. An uncertainty analysis of the measurements is also presented.

  • Experiments with Podded Propulsors in Static Azimuthing Conditions
    2007
    Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian Veitch, Neil Bose
    Abstract:

    The paper presents a comprehensive experimental study of the variations of propulsive characteristics of puller and pusher Podded Propulsors in static azimuthing open water conditions. A custom designed six-component global dynamometer and a three-component pod dynamometer were used to measure the propulsive performance of a Podded unit in pusher and puller configurations in a towing tank. The unit was tested to measure the forces on the whole unit in the three co-ordinate directions as well as thrust and torque of the propeller for a range of advance coefficients combined with the range of static azimuthing angles from +30° to –30° with 5° and 10° increments. The variations in propulsive performance of the unit with change of azimuthing angle and advance speed in the two configurations were examined. The results of the measurements are presented as changes of forces and moments of the propulsor unit with advance coefficients and azimuthing angles. The results illustrate that the axial and side forces and the steering moment are complex functions of the azimuthing angles both for puller and pusher Propulsors.

Akinturk A - One of the best experts on this subject based on the ideXlab platform.

  • Experiments with Podded Propulsors in Static Azimuthing Conditions
    2015
    Co-Authors: Islam M. F, Akinturk A, Veitch B, Bose N., Liu P
    Abstract:

    Archives des publications du CNRC Experiments with Podded Propulsors in static azimuthing condition

  • Study of Podded Propulsors with varied bub angle and configurations
    2009
    Co-Authors: Islam M. F, Veitch B, Liu P, Akinturk A
    Abstract:

    This paper presents an experimental study on the effects of tapered hub on the propulsive characteristics of puller and pusher Podded Propulsors in straight course and static azimuthing conditions while operating in open water. The propulsive performance of two model pod units having the same pod-strut shape and propeller blade geometry with different hub shapes were measured using a custom designed pod dynamometer. The dynamometer system consisted of a six-component global dynamometer and a three-component pod dynamometer. The measurements consisted of the forces and moments of the units in the three co-ordinate directions and thrust and torque of the propellers for a range of advance coefficients from 0 to 1.2 combined with the range of static azimuthing angles from +30\ub0 to \u201330\ub0 in 15\ub0 increments in pusher and puller configurations. The variations in the propulsive performance due to the change in hub geometry in straight ahead conditions were examined first, followed by a study on the effects in different static azimuthing angles. Comparison of the results of the two pod units illustrated that in both pusher and puller configurations, the effect of hub taper angle is more significant at lower advance coefficients while the effects increased with increasing azimuthing angle.Peer reviewed: NoNRC publication: Ye

  • Ice loads acting on a model Podded propeller blade
    2007
    Co-Authors: Wang J., Akinturk A, Bose N., Jones S. J., Kim M. C., Chun H. H.
    Abstract:

    With the increase in popularity of Podded Propulsors and arctic navigation, understanding the interaction between a Podded propulsor and ice has become more important. Propeller-ice interaction itself is a complicated process with a high level of uncertainty resulting from the uncertainties associated with the properties of the ice and with the propeller-ice interaction conditions. Model tests provide relatively well-controlled ice properties and interaction conditions to reduce the uncertainties. In order to improve the understanding of this interaction and to develop numerical models of it, a model Podded propulsor was used in ?Puller? mode, and ice loads were measured on its instrumented blade and propeller shaft. The results of the experiments conducted to simulate the interactions (milling) of the instrumented blade with ice in different operating conditions are reported in this paper. Loads measured during the milling consist of ice milling loads, ?inseparable? hydrodynamic loads and ?separable? hydrodynamic loads. The sample results presented here include ice milling and inseparable hydrodynamic loads for various advance coefficients and depths of cut (amount of blade penetration into ice). Some results are compared with existing ice load models.Peer reviewed: YesNRC publication: Ye

  • Gap effect on performance of Podded Propulsors in straight and static azimuthing conditions
    2007
    Co-Authors: Islam M., Akinturk A, Veitch B, Macneill A., Liu P
    Abstract:

    The paper presents preliminary results of an experimental study on the effect of gap distance on propulsive characteristics of puller Podded Propulsors in straight course and static azimuthing open water conditions. The gap distance is the axial distance between the rotating (propeller) and stationary (pod) part of a Podded propulsor. The propeller thrust and torque, unit forces and moments in the threecoordinate directions of a Podded unit were measured using a custom designed pod dynamometer in puller configurations with varied operating conditions. The model propulsor was tested at the gap distances of 0.3%, 1% and 2% of propeller diameter for a range of advance coefficients combined with the range of static azimuthing angles from +20\ub0 to ?20\ub0 in a 10\ub0 increment. The results show that the gap distance does not have significant effect on propeller torque in straight course conditions, but has effects in azimuthing conditions. The propeller thrust and efficiency were influenced by the change of gap distance and the effects were more obvious at high azimuthing angles and high advance coefficient values. The unit thrust and efficiency, transverse and vertical forces, as well as moments in three coordinate directions were not influenced by the gap distance, taking into account the uncertainty in the measurements, both in straight course and azimuthing conditions.NRC publication: Ye

  • Experiments with Podded Propulsors in static azimuthing conditions
    2007
    Co-Authors: Islam M., Akinturk A, Veitch B, Bose N., Liu P
    Abstract:

    The paper presents a comprehensive experimental study of the variations of propulsive characteristics of puller and pusher Podded Propulsors in static azimuthing open water conditions. A custom designed six-component global dynamometer and a three-component pod dynamometer were used to measure the propulsive performance of a Podded unit in pusher and puller configurations in a towing tank. The unit was tested to measure the forces on the whole unit in the three co-ordinate directions as well as thrust and torque of the propeller for a range of advance coefficients combined with the range of static azimuthing angles from +30\ub0 to ?30\ub0 with 5\ub0 and 10\ub0 increments. The variations in propulsive performance of the unit with change of azimuthing angle and advance speed in the two configurations were examined. The results of the measurements are presented as changes of forces and moments of the propulsor unit with advance coefficients and azimuthing angles. The results illustrate that the axial and side forces and the steering moment are complex functions of the azimuthing angles both for puller and pusher Propulsors.NRC publication: Ye

Ayhan Akinturk - One of the best experts on this subject based on the ideXlab platform.

  • performance study of Podded propulsor in static azimuthing conditions
    International shipbuilding progress, 2009
    Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian Veitch, N Bose
    Abstract:

    This paper presents a comprehensive experimental study on variations of propulsive characteristics of puller and pusher Podded Propulsors in static azimuthing open water conditions. A custom designed experimental apparatus consisting of a six-component global dynamometer and a three-component pod dynamometer was used to measure the propulsive performance of a model pod unit in pusher and puller configurations in a towing tank. The pod model was tested to measure the forces on the whole unit as well as thrust and torque of the propeller shaft for a range of advance coefficients combined with a range of static azimuth angles from +30° to −30°. The variations in forces and moments of the propulsor unit with change of azimuth angle and advance speed are presented in non-dimensional forms. The results illustrate that the propeller thrust and torque as well as the unit axial, side forces and the steering moment are complex functions of the azimuth angle and propeller loading.

  • Experiments with Podded Propulsors in Static Azimuthing Conditions
    2007
    Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian Veitch, Neil Bose
    Abstract:

    The paper presents a comprehensive experimental study of the variations of propulsive characteristics of puller and pusher Podded Propulsors in static azimuthing open water conditions. A custom designed six-component global dynamometer and a three-component pod dynamometer were used to measure the propulsive performance of a Podded unit in pusher and puller configurations in a towing tank. The unit was tested to measure the forces on the whole unit in the three co-ordinate directions as well as thrust and torque of the propeller for a range of advance coefficients combined with the range of static azimuthing angles from +30° to –30° with 5° and 10° increments. The variations in propulsive performance of the unit with change of azimuthing angle and advance speed in the two configurations were examined. The results of the measurements are presented as changes of forces and moments of the propulsor unit with advance coefficients and azimuthing angles. The results illustrate that the axial and side forces and the steering moment are complex functions of the azimuthing angles both for puller and pusher Propulsors.

  • ice loads acting on a model Podded propeller blade omae2005 67416
    Journal of Offshore Mechanics and Arctic Engineering-transactions of The Asme, 2007
    Co-Authors: Jungyong Wang, Ayhan Akinturk, Stephen J Jones, N Bose, Hohwan Chun
    Abstract:

    With the increase in popularity of Podded Propulsors and arctic navigation, understanding the interaction between a Podded propulsor and ice has become more important. Propeller-ice interaction itself is a complicated process with a high level of uncertainty resulting from the uncertainties associated with the properties of the ice and with the propeller-ice interaction conditions. Model tests provide relatively well-controlled ice properties and interaction conditions to reduce the uncertainties. In order to improve the understanding of this interaction and to develop numerical models of it, a model Podded propulsor was used in “Puller” mode, and ice loads were measured on its instrumented blade and propeller shaft. The results of the experiments conducted to simulate the interactions (milling) of the instrumented blade with ice in different operating conditions are reported in this paper. Loads measured during the milling consist of ice milling loads, “inseparable” hydrodynamic loads, and “separable” hydrodynamic loads. The sample results presented here include ice milling and inseparable hydrodynamic loads for various advance coefficients and depths of cut (amount of blade penetration into ice). Some results are compared with existing ice load models. DOI: 10.1115/1.2426993

  • ice loads on azimuthing Podded Propulsors
    ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering, 2004
    Co-Authors: Ayhan Akinturk, Dale Duffy, Stephen J Jones, Barbara Rowell
    Abstract:

    The paper describes the experimental setup and presents some of the results obtained. The experimental system is designed and built to measure the loads on the blade, on the propeller shaft bearings, on the shaft, and on the whole propulsion unit (global loads). Experiments have been conducted at various headings form 0° to 180°, thrust directions (aft or forward), and advance coefficients. In the experiments, ice sheets of 60 mm thickness were used. Target flexural strength of the ice sheets was 60 kPa at the start of the experiments. During the course of the experiments, thickness, flexural, compressive and shear strength values of the ice sheets were sampled at certain time intervals in order to record the variations in the ice properties. Initial results suggest that there was an increase of the loads exerted on the Podded system due to ice. The increase varies at different azimuth angles and advance velocities.Copyright © 2004 by ASME