Design Stage

Home   |   Services   |   Engineering   |   Design Stage

Noise and Vibration Control:

In most cases a noise and vibration consultant is hired by the Yard after the contract is signed.

This in our opinion is not the best approach as noise and vibration targets are copied and paste from previous projects.

Case study:

In most cases a noise and vibration consultant is hired by the Yard after the contract is signed.

The above shown image Numarine 37XP project is launched in 2021. Silent Line entered into this project from the early Design Stage and we achieved stunning low noise and vibration levels.

Active noise and vibration control:

Active noise and vibration control, reduce noise and vibration levels at the sound sources as much as possible, is the first topic we look into meaning:

  • Selection of main engine and gearbox
  • Selection of propulsion propellers
  • Selection of generator sets and sound shields
  • Selection of air conditioning (HVAC) system
  • More

Preliminary Insulation Plan (P.I.P), weight distribution and space requirements:

Prior to the design of the Insulation Plans (detailed insulation | installation drawings) we prepare a detailed Excel Sheet indicating the selection of engineering-based insulation materials (Sound Deadening | Thermal | Fire Protection and Comfort Insulation).

This Excel sheet is also used for weight distribution per cabin or deck which is important information for the Designer (stability calculations).

Last but not least we point out the space required in order to install the above-mentioned products including separation walls for acoustic privacy. This information is important for the Interior Designer.

In the Design Stage we also look into the position of the fan coil units (FCU) and position of air inlets and outlets along with the size of the openings in order to achieve low air-flow and extremely low noise levels emitted by air conditioning.

Predicted noise levels by Computer Simulation:

After we completed the afore mentioned studies we proceed with noise predictions by computer simulation meaning which noise levels can be achieved for this project other than copy-paste noise levels from previous projects.

The end result on this Numarine 32XP project:

Noise and Vibration measurements are carried out during the official sea trails in 2017 and we achieved:

  • 22 dB(A) in Guest and VIP areas on lower deck with the generator set running. Even lower noise levels in the Master Stateroom on Main deck.
  • 34 dB(A) in Guest and VIP areas on lower deck with the generator set and AC running. Even lower noise levels in the Master Stateroom on Main deck.
  • 42 dB(A) in Guest and VIP areas on lower deck at transit condition. Even lower noise levels in the Master Stateroom on Main deck.

At anchor condition the measured vibration levels did not exceed 0.5 mm/sec [RMS] and at transit the vibration levels did not exceed 1.0 mm [RMS] in all accommodation areas.