Natural vibration on a ship model (HM 159.11)

Natural vibration on a ship model (HM 159.11)

dynamic behaviour of a ship structure

CodeHM159.11

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.