dynamic behaviour of a ship structure

Description:

• Nowadays, experiment-based vibration analysis is an essential component in shipbuilding design and development.
• The HM 159.11unit helps students take their first steps in the field of experimental vibration analysis or modal analysis of structures.
• Using this trainer, the dynamic behaviour of a ship structure is studied, teaching students the fundamentals of experimental vibration analysis.
• The HM 159.11unit can be used to measure and record the natural frequencies and modes of a model ship.
• The simple, idealised ship shape makes it easier to approach the problem mathematically.
• The plastic model ship has nine ribs and an elliptical line plan.
• The model ship is attached to a rigid cross-member by springs.
• The enclosed box cross-section with high rigidity means the natural frequency of the cross-member is negligibly high.
• An electrodynamic vibration exciter causes the model ship to vibrate.
• A function generator produces the excitation signal, which can be adjusted in amplitude and frequency.
• An arbitrarily position able acceleration sensor measures the model’s response to the excitation signal.
• In this manner, the transfer functions for various points of the model ship can be generated step by step.
• These can be used to determine the vibration modes for various natural frequencies. Experiments can also be conducted in water.
• An additional tank is required to conduct these experiments (not included).
• Complementary experiments can be conducted with additional ballast and weights.

Technical Details:

Specification:

• vibration behaviour of a model ship in air and in water (with additional tank)
• model ship mounted on springs; vibration excitation and acceleration measurement at any point
• frame with height-adjustable cross-member for attaching the model
• high natural frequency of the cross-member owing to enclosed box cross-section with high rigidity and low weight
• plastic model ship with elliptical lines plan and 9 ribs
• capacitive acceleration sensor with measuring amplifier, freely positionable
• vibration exciter with power amplifier and function generator: sinusoidal, triangular or rectangular signal
• possible to display measured values on an oscilloscope (not included)

Technical Data:

• Vibration exciter
  • electrodynamic type with permanent magnet
  • force: 8,9N
  • frequency range: 5…12000Hz
• Function generator
  • adjustable frequency, amplitude and offset
  • output: 0…10Vss, 50 Ohm
• Acceleration sensor
  • measuring range: ±5g
  • frequency range: 0…400Hz
• Model ship
  • deck stringer with fastening holes for sensors and suspension
• 230V, 50Hz, 1 phase
• 230V, 60Hz, 1 phase; 120V, 60Hz, 1 phase
• UL/CSA optional

Dimensions & Weight:

• L x W x H: 1800x400x1700mm (frame)
• L x W x H: 1200x200x150mm (model)
• Weight: approx. 50kg

Learning Objections/Experiments:

• measure and record natural frequencies and modes of the model ship (in air)
• vibration behaviour of the model shipping air
• comparison between theory (approximation formula for determining the first bending frequency) and practice (measured natural frequency)
• influence of discrete additional masses or ballast on natural frequency and mode (ballast and extra weights not included)
• vibration behaviour of floating model ship (possible with additional tank)

Scope of Delivery:

• 1 trainer
• 1 model ship
• 4 springs
• 1 measuring amplifier
• 1 power amplifier
• 1 vibration exciter
• 1 function generator
• 2x multimeter
• 1 acceleration sensor
• 1 set of cables
• 1 set of instructional material

Features:

• dynamic behaviour of a ship structure
• simple ship form simplifies the mathematical approach
• different excitation signals possible
• optional excitation and measuring points

Due to the continuous development of our products, the goods supplied may vary in detail to that illustrated on this Website.