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Mohammed Islam - One of the best experts on this subject based on the ideXlab platform.
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Performance aspects of Podded Propulsor in dynamic operating conditions
International Shipbuilding Progress, 2016Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian VeitchAbstract:This paper presents various aspects of propulsive performance of a dynamic azimuthing puller Podded Propulsor in open water condition derived from an experimental research. A model Podded Propulsor was instrumented to measure thrust, torque and rotational speed of the propeller, three orthogonal forces and moments, azimuthing angle and azimuthing rate of the unit. Experiments were carried out in which the azimuthing angle was varied dynamically at multiple azimuthing rates and propeller rotational speeds for different advance speeds. The model Podded Propulsor was capable of azimuthing or yawing continuously in the range of −180° to +180°, 0° (straight-ahead) being the design operating condition and positive azimuthing means a counter-clockwise rotation. The performance coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. The open water characteristics were mostly irregular for the astern thrust conditions in the azimuthing angle beyond the normal inflow condition and the fluctuation of the magnitude of the performance coefficients showed a considerable range. The azimuthing rate showed little or no effect on the performance coefficients in the range of azimuthing angles examined. Both at high and moderate propeller loading conditions, an increase in the shaft speed resulted in slight change in the performance coefficients and the change was more obvious as the azimuthing angle was increased. The increase in the performance coefficients due to the increase of propeller shaft speed was not noticeably affected by the change of azimuthing rate.
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Hydrodynamics of Podded Propulsors With Highly Loaded Propellers and in Extreme Azimuthing Conditions
Volume 11: Prof. Robert F. Beck Honoring Symposium on Marine Hydrodynamics, 2015Co-Authors: Mohammed Islam, Ron Ryan, Fatima Jahra, Lee HeddAbstract:State of the art CFD capabilities has enabled the accurate prediction of forces and moments on the propeller as well as on the pod-strut body due to small to moderate azimuthing angles. The capability of CFD to predict the hydrodynamics at extreme azimuthing angles is yet to be demonstrated. The aim of this research is to develop a simulation capability to capture most of the dynamics of Podded propulsion systems in regular to extreme operating conditions. The numerical methodologies to evaluate the hydrodynamic characteristics of Podded Propulsors in puller configurations in extremely oblique inflow and highly loaded condition in open water and the associated results are presented in this paper.A numerical study is carried out to predict the hydrodynamic forces of a Podded Propulsor unit in various extreme static azimuthing conditions. An unsteady Reynolds-Averaged Navier Stokes (RANS) solver is used to predict the propulsive performance of the Podded Propulsor system in puller configuration using both steady and unsteady state solutions. To obtain insight into the reliability and accuracy of the results, grid dependency studies are conducted for a Podded Propulsor in straight-ahead condition. RANS solver simulation technique is first validated against measurements of a puller Podded Propulsor in straight ahead condition for multiple loading scenarios. The propeller thrust and torque as well as the forces and moments of the pod unit in the three coordinate directions in straight-ahead condition and at static azimuthing angles in the range of −180° to 180° at advance coefficient of 0.20 are then compared with that of the measurements. Additionally, the velocity and pressure distribution on and around the pod-strut-propeller bodies are presented as derived from the RANS predictions. Analysis demonstrates that the RANS solver can predict the performance coefficients of the Podded Propulsor in extreme azimuthing and in the highly loaded conditions within the same level of accuracy of the same order of magnitude of the experimental results.Copyright © 2015 by ASME
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Numerical Research on Usage of Podded Propulsors in Ice Management
All Days, 2015Co-Authors: Mohammed Islam, Fatima Jahra, David Molyneux, Lee HeddAbstract:Abstract Although Podded Propulsor technology has existed for nearly two decades, there has been little research into the use of these Propulsors for ice management. Full-scale ice management trials with azimuthing thrusters revealed that it was possible to break and clear ice with the Propulsors' wake and that precise ice management could be achieved with the wake of this propulsion system. This means dynamic placement ofpropeller wake wash can facilitate ice breaking and ice management operations. This paper presents preliminary outcome of a research program to evaluate the potentials ofPodded Propulsors as an ice management device. The kinematics i.e. the turbulence and velocity distribution in the propeller wake wash determines the capacity of the Propulsor to break, push and clear the ice. In this research, efforts are made to model the propeller wash and data were predicted to quantify the capacity of a Podded Propulsor to clear ice under a range of operating conditions. A Reynolds-Averaged Navier-Stokes solver is used to predict the propulsive performance of a generic Podded Propulsor system in various operating conditions and configurations. The effects ofpropeller shaft speed and pod configuration are evaluated. The predicted propeller thrust and torque as well as the loads on the pod are compared with corresponding data acquired in a complimentary experimental program. The simulations and measurements are carried out for both puller and pusher configurations at or near bollard pull condition and in uniform inflow condition. Analysis demonstrates that the RANS solver can accurately predict the performance coefficients of the Podded Propulsor in straight-ahead condition in both puller and pusher configurations. The kinematics of the propeller wash at multiple downstream locations are studied only to reveal that the pusher Propulsor may be more effective in clearing ice than the puller one because of less interaction between the propeller and the strut. The current work aims to provide insight into the effect of propeller shaft speed and pod configurations on the quality of the propeller wake that can be used for ice management.
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Some Unsteady Propulsive Characteristics of a Podded Propeller Unit under Maneuvering Operation
2015Co-Authors: Pengfei Liu, Mohammed Islam, Brian VeitchAbstract:Propulsion dynamics of a Podded Propulsor unit in steering motion at fixed azimuth angles were investigated numerically. Unsteady forces, torques and bending moments were predicted for a model Podded Propulsor unit at various azimuth angles. Analysis was performed for averaged forces and their fluctuations as well. A time-domain unsteady multi-body panel method code, PROPELLA, was further developed for this work. Predictions were compared with a set of time averaged in-house experimental data for a puller type Podded Propulsor configuration in the first quadrant operation. Unsteady fluctuations of forces were predicted numerically. Analysis was made for the bending moment on propeller blades, shaft and the Propulsor unit stock shaft for azimuth angles from 0 to 45 degrees. It indicates that the magnitude and fluctuation of the forces are significant and they are essential for structural strength and design optimization. The predicted bending moment and global forces on the Propulsor unit provide some useful data for ship maneuvering motion and simulation at off design conditions
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Numerical and Experimental Research on a Podded Propulsor
Volume 8B: Ocean Engineering, 2014Co-Authors: Mohammed Islam, Ron Ryan, David MolynuexAbstract:This paper presents methodologies and some results of a numerical and experimental program to evaluate the effects of static azimuthing conditions on the propulsive characteristics of a puller Podded Propulsor in open water. In the experimental effort, the model Propulsor was instrumented to measure thrust, torque and rotational speed of the propeller, and three orthogonal forces and moments, and azimuthing angle of the pod. The experimental results included the bare propeller (ahead only) and the combined propeller and pod over a range of advance coefficients at various static azimuthing angles in the range of −180° to 180°.A complementary numerical study is being carried out to predict the hydrodynamic forces of Podded Propulsor in static azimuthing conditions. A Reynolds-Averaged Navier Stokes solver is used to predict the propulsive performance of the bare propeller as well as the Podded Propulsor system. The thrust and torque for the bare propeller were compared to the corresponding measurements. The propeller thrust and torque as well as the loads on the pod in straight-ahead condition and at static azimuthing angles were then compared with the measurements. Preliminary analysis demonstrates that the RANS solver could predict the performance coefficients of the bare propeller as well as the Podded Propulsor in straight-ahead and static azimuthing angles in puller configurations.Copyright © 2014 by ASME
Brian Veitch - One of the best experts on this subject based on the ideXlab platform.
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Performance aspects of Podded Propulsor in dynamic operating conditions
International Shipbuilding Progress, 2016Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian VeitchAbstract:This paper presents various aspects of propulsive performance of a dynamic azimuthing puller Podded Propulsor in open water condition derived from an experimental research. A model Podded Propulsor was instrumented to measure thrust, torque and rotational speed of the propeller, three orthogonal forces and moments, azimuthing angle and azimuthing rate of the unit. Experiments were carried out in which the azimuthing angle was varied dynamically at multiple azimuthing rates and propeller rotational speeds for different advance speeds. The model Podded Propulsor was capable of azimuthing or yawing continuously in the range of −180° to +180°, 0° (straight-ahead) being the design operating condition and positive azimuthing means a counter-clockwise rotation. The performance coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. The open water characteristics were mostly irregular for the astern thrust conditions in the azimuthing angle beyond the normal inflow condition and the fluctuation of the magnitude of the performance coefficients showed a considerable range. The azimuthing rate showed little or no effect on the performance coefficients in the range of azimuthing angles examined. Both at high and moderate propeller loading conditions, an increase in the shaft speed resulted in slight change in the performance coefficients and the change was more obvious as the azimuthing angle was increased. The increase in the performance coefficients due to the increase of propeller shaft speed was not noticeably affected by the change of azimuthing rate.
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Some Unsteady Propulsive Characteristics of a Podded Propeller Unit under Maneuvering Operation
2015Co-Authors: Pengfei Liu, Mohammed Islam, Brian VeitchAbstract:Propulsion dynamics of a Podded Propulsor unit in steering motion at fixed azimuth angles were investigated numerically. Unsteady forces, torques and bending moments were predicted for a model Podded Propulsor unit at various azimuth angles. Analysis was performed for averaged forces and their fluctuations as well. A time-domain unsteady multi-body panel method code, PROPELLA, was further developed for this work. Predictions were compared with a set of time averaged in-house experimental data for a puller type Podded Propulsor configuration in the first quadrant operation. Unsteady fluctuations of forces were predicted numerically. Analysis was made for the bending moment on propeller blades, shaft and the Propulsor unit stock shaft for azimuth angles from 0 to 45 degrees. It indicates that the magnitude and fluctuation of the forces are significant and they are essential for structural strength and design optimization. The predicted bending moment and global forces on the Propulsor unit provide some useful data for ship maneuvering motion and simulation at off design conditions
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Performance Characteristics of Static and Dynamic Azimuthing Podded
2015Co-Authors: Mohammed F. Islam, Ayhan Akinturk, Brian Veitch, Pengfei LiuAbstract:This paper presents results and analyses of an experimental study into the effects of static and dynamic azimuthing conditions on the propulsive characteristics of a puller Podded unit in open water. The model Propulsor was instrumented to measure thrust and torque of the propeller, three orthogonal forces and moments on the unit, rotational speed of the propeller, azimuthing angle and azimuthing rate. The model was first tested over a range of advance coefficients at various static azimuthing angles in the range of 0 ° to 360°. These tests were followed by tests in which the azimuthing angle was varied dynamically at different azimuthing rates and propeller rotational speeds. The performance coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. The open water characteristics were mostly irregular for the astern thrust conditions in the azimuthing angle beyond the range 90 ° to 270°, where the flow separation at the propeller blades and the pod-strut body might have occurred. The coefficients in static azimuthing conditions fit well with a 10th order polynomial fit of the data obtained in the dynamic azimuthing condition in the corresponding azimuthing angles and advance coefficients. An uncertainty analysis of the measurements is also presented. Keywords Podded Propulsor; static and dynamic azimuthing; propulsive performance; global forces and moments.
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uncertainty of measurements of Podded Propulsor performance characteristics
Ocean Engineering, 2014Co-Authors: Mohammed Islam, Brian VeitchAbstract:One of the fundamental aspects of any physical experiment is the uncertainty or error limits of the measurement. Unfortunately, majority of published model experimental results do not come with the much needed error analysis. It is imperative that a fundamental and rigorous uncertainty assessment is carried out for all measurements, especially for measurements using a newly designed apparatus. This paper presents the uncertainty analysis methodology and results for a newly designed fully functional Podded Propulsor performance measurement apparatus. The measurements include propeller thrust, torque, rotation rate and advance speed as well as global forces and moments of a pod unit. The facility and measurement systems are briefly described, and detailed uncertainty assessment methodologies with examples for each measurement are provided with descriptions of bias and precision limits and total uncertainties. The generalized methodology can also be used for other relevant measurements.
Ayhan Akinturk - One of the best experts on this subject based on the ideXlab platform.
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Performance aspects of Podded Propulsor in dynamic operating conditions
International Shipbuilding Progress, 2016Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian VeitchAbstract:This paper presents various aspects of propulsive performance of a dynamic azimuthing puller Podded Propulsor in open water condition derived from an experimental research. A model Podded Propulsor was instrumented to measure thrust, torque and rotational speed of the propeller, three orthogonal forces and moments, azimuthing angle and azimuthing rate of the unit. Experiments were carried out in which the azimuthing angle was varied dynamically at multiple azimuthing rates and propeller rotational speeds for different advance speeds. The model Podded Propulsor was capable of azimuthing or yawing continuously in the range of −180° to +180°, 0° (straight-ahead) being the design operating condition and positive azimuthing means a counter-clockwise rotation. The performance coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. The open water characteristics were mostly irregular for the astern thrust conditions in the azimuthing angle beyond the normal inflow condition and the fluctuation of the magnitude of the performance coefficients showed a considerable range. The azimuthing rate showed little or no effect on the performance coefficients in the range of azimuthing angles examined. Both at high and moderate propeller loading conditions, an increase in the shaft speed resulted in slight change in the performance coefficients and the change was more obvious as the azimuthing angle was increased. The increase in the performance coefficients due to the increase of propeller shaft speed was not noticeably affected by the change of azimuthing rate.
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Performance Characteristics of Static and Dynamic Azimuthing Podded
2015Co-Authors: Mohammed F. Islam, Ayhan Akinturk, Brian Veitch, Pengfei LiuAbstract:This paper presents results and analyses of an experimental study into the effects of static and dynamic azimuthing conditions on the propulsive characteristics of a puller Podded unit in open water. The model Propulsor was instrumented to measure thrust and torque of the propeller, three orthogonal forces and moments on the unit, rotational speed of the propeller, azimuthing angle and azimuthing rate. The model was first tested over a range of advance coefficients at various static azimuthing angles in the range of 0 ° to 360°. These tests were followed by tests in which the azimuthing angle was varied dynamically at different azimuthing rates and propeller rotational speeds. The performance coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. The open water characteristics were mostly irregular for the astern thrust conditions in the azimuthing angle beyond the range 90 ° to 270°, where the flow separation at the propeller blades and the pod-strut body might have occurred. The coefficients in static azimuthing conditions fit well with a 10th order polynomial fit of the data obtained in the dynamic azimuthing condition in the corresponding azimuthing angles and advance coefficients. An uncertainty analysis of the measurements is also presented. Keywords Podded Propulsor; static and dynamic azimuthing; propulsive performance; global forces and moments.
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Performance of dynamic azimuthing Podded Propulsor
International shipbuilding progress, 2012Co-Authors: Ayhan Akinturk, Mohammed Islam, Brian Veitch, Pengfei LiuAbstract:This paper presents results and analyses of an experimental study into the effects of static and dynamic azimuthing conditions on the propulsive characteristics of a puller Podded unit in open water. The model Propulsor was instrumented to measure thrust and torque of the propeller, three orthogonal forces and moments on the unit, rotational speed of the propeller, azimuthing angle and azimuthing rate. The model was first tested over a range of advance coefficients at various static azimuthing angles in the range of-180° to 180°. These tests were followed by tests in which the azimuthing angle was varied dynamically at certain azimuthing rate and propeller rotational speed. A comparative study of the performance coefficients at static and dynamic azimuthing conditions in the range of-180° to 180° is presented. The performance coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. The coefficients in static azimuthing conditions fit well with a 10th order polynomial fit of the data obtained in the dynamic azimuthing condition in the corresponding azimuthing angles and advance coefficient. An uncertainty analysis of the measurements is also presented. © 2012-IOS Press and the authors.
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performance study of Podded Propulsor in static azimuthing conditions
International shipbuilding progress, 2009Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian Veitch, N BoseAbstract: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.
Pengfei Liu - One of the best experts on this subject based on the ideXlab platform.
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Some Unsteady Propulsive Characteristics of a Podded Propeller Unit under Maneuvering Operation
2015Co-Authors: Pengfei Liu, Mohammed Islam, Brian VeitchAbstract:Propulsion dynamics of a Podded Propulsor unit in steering motion at fixed azimuth angles were investigated numerically. Unsteady forces, torques and bending moments were predicted for a model Podded Propulsor unit at various azimuth angles. Analysis was performed for averaged forces and their fluctuations as well. A time-domain unsteady multi-body panel method code, PROPELLA, was further developed for this work. Predictions were compared with a set of time averaged in-house experimental data for a puller type Podded Propulsor configuration in the first quadrant operation. Unsteady fluctuations of forces were predicted numerically. Analysis was made for the bending moment on propeller blades, shaft and the Propulsor unit stock shaft for azimuth angles from 0 to 45 degrees. It indicates that the magnitude and fluctuation of the forces are significant and they are essential for structural strength and design optimization. The predicted bending moment and global forces on the Propulsor unit provide some useful data for ship maneuvering motion and simulation at off design conditions
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Performance Characteristics of Static and Dynamic Azimuthing Podded
2015Co-Authors: Mohammed F. Islam, Ayhan Akinturk, Brian Veitch, Pengfei LiuAbstract:This paper presents results and analyses of an experimental study into the effects of static and dynamic azimuthing conditions on the propulsive characteristics of a puller Podded unit in open water. The model Propulsor was instrumented to measure thrust and torque of the propeller, three orthogonal forces and moments on the unit, rotational speed of the propeller, azimuthing angle and azimuthing rate. The model was first tested over a range of advance coefficients at various static azimuthing angles in the range of 0 ° to 360°. These tests were followed by tests in which the azimuthing angle was varied dynamically at different azimuthing rates and propeller rotational speeds. The performance coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. The open water characteristics were mostly irregular for the astern thrust conditions in the azimuthing angle beyond the range 90 ° to 270°, where the flow separation at the propeller blades and the pod-strut body might have occurred. The coefficients in static azimuthing conditions fit well with a 10th order polynomial fit of the data obtained in the dynamic azimuthing condition in the corresponding azimuthing angles and advance coefficients. An uncertainty analysis of the measurements is also presented. Keywords Podded Propulsor; static and dynamic azimuthing; propulsive performance; global forces and moments.
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Performance of dynamic azimuthing Podded Propulsor
International shipbuilding progress, 2012Co-Authors: Ayhan Akinturk, Mohammed Islam, Brian Veitch, Pengfei LiuAbstract:This paper presents results and analyses of an experimental study into the effects of static and dynamic azimuthing conditions on the propulsive characteristics of a puller Podded unit in open water. The model Propulsor was instrumented to measure thrust and torque of the propeller, three orthogonal forces and moments on the unit, rotational speed of the propeller, azimuthing angle and azimuthing rate. The model was first tested over a range of advance coefficients at various static azimuthing angles in the range of-180° to 180°. These tests were followed by tests in which the azimuthing angle was varied dynamically at certain azimuthing rate and propeller rotational speed. A comparative study of the performance coefficients at static and dynamic azimuthing conditions in the range of-180° to 180° is presented. The performance coefficients of the propeller and the pod unit showed a strong dependence on the propeller loading and azimuthing angle. The coefficients in static azimuthing conditions fit well with a 10th order polynomial fit of the data obtained in the dynamic azimuthing condition in the corresponding azimuthing angles and advance coefficient. An uncertainty analysis of the measurements is also presented. © 2012-IOS Press and the authors.
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Unsteady hydromechanics of a steering Podded propeller unit
Ocean Engineering, 2009Co-Authors: Pengfei Liu, Mohammed Islam, Brian VeitchAbstract:Unsteady forces, torques and bending moments were predicted for a model Podded Propulsor unit at various azimuth angles. Predictions in time history include propeller shaft thrust, Propulsor unit thrust, normal forces to the propeller shaft bearing, total forces acting on the Propulsor unit, propeller shaft torque, blade spindle torque, in-plane and out-of-plane bending moments, and Propulsor unit stock shaft torque and bending moments. Analysis was performed for averaged forces and their fluctuations as well. A time-domain unsteady multi-body panel method code, PROPELLA, was further developed for this prediction work. Predictions were compared with a set of time averaged in-house experimental data for a puller-type Podded Propulsor configuration in the first quadrant operation. Unsteady fluctuations of forces were predicted numerically. Analysis was made for the bending moment on propeller blades, shaft and the Propulsor unit stock shaft for azimuth angles from 0° to 45°. It indicates that the magnitude and fluctuation of the forces are significant and they are essential for structural strength and design optimization. The predicted bending moment and global forces on the Propulsor unit provide some useful data for ship maneuvering motion and simulation in off-design conditions.
N Bose - One of the best experts on this subject based on the ideXlab platform.
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performance study of Podded Propulsor in static azimuthing conditions
International shipbuilding progress, 2009Co-Authors: Mohammed Islam, Ayhan Akinturk, Brian Veitch, N BoseAbstract: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.
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ice loads acting on a model Podded propeller blade omae2005 67416
Journal of Offshore Mechanics and Arctic Engineering-transactions of The Asme, 2007Co-Authors: Jungyong Wang, Ayhan Akinturk, Stephen J Jones, N Bose, Hohwan ChunAbstract: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
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numerical study of hub taper angle on Podded propeller performance
Marine Technology and Sname News, 2006Co-Authors: Mohammed Islam, Brian Veitch, N BoseAbstract:Presently, the majority of Podded propulsion systems are of the pulling type, because this type provides better hydrodynamic efficiency than the pushing type. There are several possible explanations for the better overall performance of a puller-type Podded Propulsor. One is related to the difference in hub taper angle. Puller and pusher propellers have opposite hub taper angles, hence different hub and blade root shape. These differences cause changes in the flow condition and possibly influence the overall performance. The current study focuses on the variation in performance of pusher and puller propellers with the same design of blade sections, but different hub taper angles. A hyperboloidal low-order source-doublet steady/unsteady time domain panel method code, PROPELLA, was modified and used to evaluate effects of hub taper angle on the open water propulsive performance of some fixed-pitch screw propellers used in Podded propulsion systems. Major findings include good agreement between predictions using the modified code and measurements, significant effects of hub taper angle on propulsive performance of tapered hub propellers, and noticeable effects of hub taper angle on sectional pressure distributions of tapered hub propeller blades.