Textos de Apoio (pdf)

ITTC – Recommended
7.5-04
-01-01.1
Procedures and Guidelines Page 5 of 10
Full Scale Measurements
Speed and Power Trials
Preparation and Conduct of
Speed/Power Trials
Effective Date
2005
Revision
03
4.2 Ship Inspection
There are three stages of a ship inspection:
in-house preparation, the actual inspection, and
the reporting of results and distribution of information
to the various parties involved in the
trial.
4.2.1 Preparation for the trials
• Review shafting dimensions, propulsion
plant specifications, etc.
• Review trials agenda, if available.
4.2.2 Ship Inspection
• Inspect hull- and propeller surface condition,
if possible.
• Inspect ship’s instrumentation for accessibility.
• Determine routes for cable runs/data
transfer conduits between trial room
and bridge or control area.
• Contact the Engineer on duty to discuss
trial instrumentation requirements. Inspect
machinery spaces as applicable.
4.2.3 Reporting of Results and Distribution
of Information
Document all pertinent information related
to the ship inspection
a) Last date of cleaning.
b) Means of cleaning.
c) Propeller roughness measurement, if
available, which should include average,
standard deviation, distribution
along the blades, and existing physical
damage.
d) For a clean hull; documentation indicating
manufacturer and kind of paint
used, paint layer thickness and, if available,
roughness measurements (average,
standard deviation, and distribution
along the hull) should be provided. The
majority of this information may be
contained in the docking report.
e) For a dirty hull, documentation indicating
visual observations of any fouling
and date of last dry-docking should
be provided.
4.3 Hull- and Propulsor Survey
A roughness survey is recommended to
document the conditions of the ship hull, appendages,
and propulsor(s) prior to the start of
the full-scale speed/ power trial. Cleaning may
be required if fouling is found to be such that it
would bias the trial data.
Ideally, roughness surveys should be conducted
prior to the trials. The average hull
roughness should not exceed 250 µm (µ =
1x10 -6 m) (6.35 mils) and the average propulsor
roughness level should not be greater than
150 µm (3.81 mils).
4.4 Instrumentation Installation and Calibration
4.4.1 Instrumentation Installation
The installation of instrumentation should
be scheduled at a time of minimal conflict with
ship operations.