New Analysis of a Voith-Schneider-Propeller in SIMPACK · 2019. 12. 23. · Page 2 dimensioning: ship hull, thruster housing, blades, couplings, motor, drive train, … dimensioning:

3DEXPERIENCE Conference 2019 – Design, Modeling & Simulation21 November 2019 | Darmstadt

Dr.-Ing. Thomas Rosenlöcher, Maximilian Rösner, Prof. Dr.-Ing. Berthold SchlechtInstitut für Maschinenelemente und Maschinenkonstruktion Lehrstuhl Maschinenelemente

Analysis of a Voith-Schneider-Propeller in SIMPACK

Analysis of a Voith-Schneider-Propeller in SIMPACK3DEXPERIENCE Conference 2019 / Dr.-Ing. Thomas Rosenlöcher21 November 2019 / Darmstadt

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dimensioning: ship hull, thruster housing, blades, couplings, motor, drive train, …

dimensioning: drive train components

standards (DIN 743, ISO 6336) software (mdesign, KissSoft, ..)

finite-element-method (Nastran, Ansys, …)

? measurement → component load ?

determination of design loads for single components by

transfer/ extrapolation of measured forces and torques

? simulation → component load ?


transfer/ extrapolation of simulated forces and torques

loads loads

multibody-system simulation (MBS)

calculation of design loads for single components by

recalculation of measured or simulated load cases

global load assumptions (forces/torques hub, motor)

measurement of forces and torques at thruster

simulation of propeller loads (CFD)


Page 3

dimensioning: ship hull, thruster housing, blades, couplings, motor, drive train, …

dimensioning: drive train components

standards (DIN 743, ISO 6336) software (mdesign, KissSoft, ..)

finite-element-method (Nastran, Ansys, …)

? measurement → component load ?


transfer/ extrapolation of measured forces and torques

? simulation → component load ?


transfer/ extrapolation of simulated forces and torques

loads loads

multibody-system simulation (MBS)

calculation of design loads for single components by

recalculation of measured or simulated load cases

global load assumptions (forces/torques hub, motor)

measurement of forces and torques at thruster

simulation of propeller loads (CFD)

paddle wheel conventional screw propeller

Voith-Schneider propeller

www.saechsische-dampfschiffahrt.de www.maritimepropulsion.com www.voith.com

azimuth thruster

www.schottel.de


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Outlook

Introduction

History

Function

Basic principle

Mathematical description (kinematic, speeds and forces)

Multibody-system model of the VSP

Simulation of operational conditions

Conclusion


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— Combination of propulsion and steering for good manoeuvrability and positioning

— Consists of circularly arranged rudder blades rotating around vertical axis

— Adjustment of pitch of blades over rotation by lever mechanism

— Definition of direction of propulsion

— With two propellers sideways movement is possible

— Used in tugs, ferries, minesweepers and floating cranes since 1927


Tugboat with two propellers arranged one behind the other


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History

— Voith-Schneider propeller: company J. M. Voith GmbH + inventor Ernst Schneider

— Schneider made invention during his student days through theoretical considerations

— No tests carried out at the beginning

— End of 1925: Schneider applied for patent (Austria, France and Germany)

— With a small test model Schneider was able to convince Voith of his drive system

— First demonstration boat “Torqueo”, powered by a 60 HP gasoline engine was built in 1929


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Function

— Vertically arranged rudder blades rotate around a common axis

— Blades pitched periodically around their own axis

— Rotation generates propulsion and allows to steer the ship at the same time

— Change from forward to reverse travel without changing of direction of rotation

— For steering it is not necessary that the rudder is flown with a sufficiently high velocity

— Single wing moves through the water on a cycloidal path - cycloidal propeller


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Basic principle

— Drive in neutral position, rotor blades tangentially positioned on circular path

− No force applied by rotor blades, regardless of applied speed

— Deflected at constant angle causes different inflow - pressure difference - force effect

— When wings deflected unevenly, thrust force generation to the left

− Vertical forces must neutralize each other

— Conditions with so-called normal law fulfilled (normal of rudders must always meet at control point S at all times)


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Mathematical description

— Kinematic description of joint position points by calculation of angles as function of leading point vector (∆L) and lengths of levers

— Center of drive: simple four-joint gearbox (B0-B-A-A0) ൰∆𝐿 = (𝐿1 cos 𝛿

𝐿1 sin 𝛿

൰𝐴 = (𝐿2 cos 𝜑

𝐿2 sin 𝜑

൰𝐵 = (𝐿4 cos 𝜓 + 𝐿1 cos 𝛿

𝐿4 sin 𝜓 + 𝐿1 sin 𝛿

൰𝑆(4) = (𝐿41 cos 𝜓 + 𝐿1 cos 𝛿

𝐿41 sin 𝜓 + 𝐿1 sin 𝛿

൰𝐻 = (𝐿7 cos 𝜑 + 𝜀

𝐿7 sin 𝜑 + 𝜀


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— Additionally the deflection angle of the blade in relation to tangent to circle required to describe acting forces

— Angle between C, H and A0, υ can described by L6, L7 and position of C using A0-C

— Angle β between tangent at point H and lever 6, difference between υ and 90°

— Point C lies outside the circle if υ is greater than 90° and β is less than 0°

— Inner position for opposite signs


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Approach to describe action forces

— Approach to describe acting forces for multibody-system simulation model

— Using overall model to make statements to loads acting on drivetrain

— Assumption: driving speed equal to inflow velocity in direction of travel

— Combination of different speed vectors

— Position of control point S defines direction of travel


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— Inflow velocity acts correspondingly against direction of travel

— Described vectorially using control point position

— Resulting velocity (relevant for blade profile) results from superposition of inflow velocity v and circumferential velocity u


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— Orientation of speed u and v is dependent on position at circumference

— Resulting speed q with maximum and minimum at 12 and 6 o’clock

— Velocity q and coefficients for lift and drag force (dependent on angle of attack and Reynolds number) simplified describe load conditions

— Resistance force is orientated in direction of resulting inflow velocity, lift force acts at right angles to it in the direction of the centre or to the outside


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MBS model of the VSP

— Assembling of a CAD model based on the determined kinematic


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— Determination of mass and mass moment of inertia of the components


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— Assembling of a multibody system model

− Consideration of electric motor, bevel gear stage and complete mechanism

− Modelling of simplified force approach


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Analysis of mechanism geometry

— Available model allows the analysis of the influence of the mechanism geometry on resulting thrust and drag forces

pitch → worse extreme valuesthrust in driving direction→ reducessideward thrust → increasesefficiency → reducesdriving torque → reducesresisting torque → reduces


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— Sideward movement of the drive due to the sideward thrust forces

— A second Voith-Schneider propeller which rotates in the opposite direction can be used to eliminate the sideward forces


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— Joints A and B have to support the highest loads

— The joints H and A0 have to transfer torques

— The acting forces lead to a bending of the wing

maximum resulting forces

resulting forces


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Conclusion

— Kinematic description of mechanism is basis for constructive design

— Simulating operational conditions using a multibody-system model

— Simulation model will be used for further investigations

− Interactions between constructive design and resulting thrust forces

− Determination of occurring loads for drivetrain components

− Complete parameterization of geometric variables allows analysis of different drive train configurations


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»Knowledge builds bridges.«

Technische Universität DresdenFaculty of Mechanical Science and Engineering

Institute of Machine Elements and Machine DesignChair of Machine Elements

Münchner Platz 3D-01062 Dresden

www.tu-dresden.de/me

Thank you for your attention

Documents

New Analysis of a Voith-Schneider-Propeller in SIMPACK · 2019. 12. 23. · Page 2 dimensioning: ship hull, thruster housing, blades, couplings, motor, drive train, … dimensioning: