Author: pa

Hydrophone Array

Posted on by pa

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur lectus elit, porttitor quis placerat eget, porttitor eget nunc. Aliquam vel ex lectus. Sed ultricies sed nisi vitae faucibus. Integer sit amet dapibus dolor. Proin tincidunt orci a neque convallis tincidunt. Sed consectetur vel ex sit amet euismod. Praesent commodo ex id ligula porttitor semper. Morbi tempus justo id nisl mattis, eu laoreet sapien suscipit. Aenean est lacus, sodales nec varius vel, convallis sit amet nisl. Cras eleifend, ante vel tempus aliquam, tellus orci tristique nisl, nec convallis diam metus at diam. Proin egestas mauris ligula, in elementum ex efficitur eget. Praesent viverra commodo lacus, eget molestie dui molestie sed. Aliquam nec mollis quam. Phasellus euismod consectetur tincidunt. Phasellus sit amet felis elementum, bibendum dolor quis, blandit magna.

Curabitur eu massa vitae turpis laoreet molestie in eu velit. Nunc in condimentum nisl. Suspendisse potenti. Nullam ante ex, varius nec dignissim faucibus, suscipit vel eros. Aliquam condimentum nisi sit amet est vestibulum tincidunt. Quisque nisl enim, tempor in porttitor sed, ornare ac massa. Mauris sed convallis nisl. Aenean volutpat finibus turpis. Ut porta sagittis ligula congue vestibulum.

Slamming Test Stand

Posted on by pa
Slamming_Anlage
In heavy seas, especially in conjunction with high ship speeds, due to the heave and pitch motions of the ship, the bow can come out of the water. When re-immersing and exceeding a critical relative vertical velocity at the hull surface, enormous pressures and forces can occur which can cause damage to the ship due to these impacts.

To investigate this problem experimentally, a hydraulic slamming system was developed in the SVA. With this system, pitching, heaving and coupled movements can be introduced with a frequency of up to 2.0 Hz and an amplitude of up to 10 cm on model ships. It can test models with a length of 5.5 m and a moving mass of 500 kg. By measuring pressure variations in the kHz range on up to 30 measurement points, local peak pressures can be identified.

 

Technical Specifications
Max. Frequency 2 Hz
Max. Amplitude 0.1 m
Max. Model Length 5.5 m
Max. Mass 500 kg
Max. # Measurement Points 30

 

Context Related References / Research Projects

[1] Fröhlich, M.: Einsatz eines Schwingungsoszillators auf hydraulischer Basis zur Untersuchung der Slammingbelastung von Schiffen, STG-Sprechtag „Schiffe im Seegang“, Hamburg, Oktober 1998

Z Drives

Posted on by pa

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur lectus elit, porttitor quis placerat eget, porttitor eget nunc. Aliquam vel ex lectus. Sed ultricies sed nisi vitae faucibus. Integer sit amet dapibus dolor. Proin tincidunt orci a neque convallis tincidunt. Sed consectetur vel ex sit amet euismod. Praesent commodo ex id ligula porttitor semper. Morbi tempus justo id nisl mattis, eu laoreet sapien suscipit. Aenean est lacus, sodales nec varius vel, convallis sit amet nisl. Cras eleifend, ante vel tempus aliquam, tellus orci tristique nisl, nec convallis diam metus at diam. Proin egestas mauris ligula, in elementum ex efficitur eget. Praesent viverra commodo lacus, eget molestie dui molestie sed. Aliquam nec mollis quam. Phasellus euismod consectetur tincidunt. Phasellus sit amet felis elementum, bibendum dolor quis, blandit magna.

Curabitur eu massa vitae turpis laoreet molestie in eu velit. Nunc in condimentum nisl. Suspendisse potenti. Nullam ante ex, varius nec dignissim faucibus, suscipit vel eros. Aliquam condimentum nisi sit amet est vestibulum tincidunt. Quisque nisl enim, tempor in porttitor sed, ornare ac massa. Mauris sed convallis nisl. Aenean volutpat finibus turpis. Ut porta sagittis ligula congue vestibulum.

CP Propeller System

Posted on by pa

With an adjustable blade hub, the dynamic adjustment of ptich during testing is possible, for example, for stopping manoeuvres. The adjustable blade hub achieves the change of blade pitch with a multiphase motor with two limit switches built in which switch off the engine at ± 30° adjustment. The average pitch is marked on the inner hub. The angle is measured with a potentiometer. The hub is mounted on a carbon ring. The control data and the values of the potentiometers are transmitted via a slip ring assembly.

Main Parameters
Hub Diameter mm 60
Hub Length mm 57
Number of Blades — 4
Propeller Diameter mm 250

 

Flügelverstellnabe_1Flügelverstellnabe_2_small

 

Context Related References / Research Projects

[1] Steinwand, M.: Optimierung des Stoppmanövers mit Verstellpropellern und Hybridantrieben, 9. SVA-Forschungsforum, Potsdam, 28. Januar 2016

VSP Balances

Posted on by pa

VSP_Waage_1VSP_Antrieb_CAD_small

For measuring the forces on VSP (Voith Schneider Propeller) drives, special measuring balances have been developed which, in comparison with the conventional VSP balances, enable the measurement of thrust, two lateral forces, and the drive torque. The VSP balances can be used in ship models, in the towing tank, and in the cavitation tunnel.

Technical Specifications
Measurement of
Thrust ✓
Lateral Forces 2
Drive torque ✓
Torque ✓
Max. force component [N] 200
Max. torque [Nm] 8

Multicomponent Balances

Posted on by pa
Waagen_R37SRxy2

For the measurement of forces and moments on bodies within flows, 3 component and 6-component balances are available with different measurement ranges and areas of operation. The balances R37SR1 … 6 are suitable for open water tests and for use in models. The devices are designed for measurement of rudder and fin forces and to capture integral forces on thrusters. The majority of balances are equipped with a rotary table, which can be set with the angle statically and dynamically. For use with thrusters the balances are equipped with a drive motor. The total torque is detected by a torque sensor.

The balance R200 is designed for open water tests with large motors and for general force measurements. It is additionally equipped with a turntable, drive motor and torque sensor.

The balances R100, R 250 and R 350 can be used for force measurements on ships and floating or submerged structures. These allow the change in yaw, trim and angle of heel, and the application of different connections.

 

Waagen_R350_smallWaagen_R250_smallWaagen_R100b_smallWaagen_R100a_smallWaagen_R200

 

Technical Specifications Multicomponent Balances
Main Parameters R37SR 1, 2 R37SR 3, 4 R37SR 5, 6 R200 R100 R250 R300
Components 3 6 3 6 3 6 3
Forces Fmax [N] 500 500 1000 2000 1000 2500 3500
Torque Qmax [Nm] 20 20 20 20 — — —