Ships and marine technology — Measurement of changes in hull and propeller performance — Part 3: Alternative methods

ISO 19030-3:2016 outlines alternatives to the default method. Some will result in lower overall accuracy but increase applicability of the standard. Others can result in same or higher overall accuracy but includes elements which are not yet broadly used in commercial shipping. The general principles outlined and performance indicators defined are applicable to all ship types driven by conventional fixed pitch propellers, where the objective is to compare the hull and propeller performance of the same ship to itself over time. ISO 19030-3:2016 presents alternatives to measurement parameters (primary and then secondary) in Clause 4, then alternatives to measurement procedures (including alternative reference and evaluation periods) in Clause 5, describes the calculation of performance indicators in Clause 6, and finally the estimation of performance indicator accuracy in Clause 7. The structure used duplicates the structure of ISO 19030‑2 to facilitate cross-reference between the two documents. NOTE Support for additional configurations (e.g. variable pitch propellers) will, if justified, be included in later revisions of this document.

Navires et technologie maritime — Mesurage de la variation de performance de la coque et de l'hélice — Partie 3: Méthodes alternatives

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Published
Publication Date
15-Nov-2016
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9093 - International Standard confirmed
Completion Date
16-Jun-2022
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INTERNATIONAL ISO
STANDARD 19030-3
First edition
2016-11-15
Ships and marine technology —
Measurement of changes in hull and
propeller performance —
Part 3:
Alternative methods
Navires et technologie maritime — Mesurage de la variation de
performance de la coque et de l’hélice —
Partie 3: Méthodes alternatives
Reference number
ISO 19030-3:2016(E)
©
ISO 2016

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ISO 19030-3:2016(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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ii © ISO 2016 – All rights reserved

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ISO 19030-3:2016(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Measurement parameters and alternatives . 2
4.1 General . 2
4.2 Proxy for the primary measurement parameters . 2
4.2.1 General. 2
4.2.2 Proxy for speed through water measurement (speed over
ground measurement) . 2
4.2.3 Proxy for delivered power (Alternative methods for estimating delivered
power other than ISO 19030-2:2016, Annex B and Annex C) . 3
4.3 Secondary measurement parameters and alternatives . 4
4.3.1 General. 4
4.3.2 Alternative measurement of wind speed . 5
4.3.3 Alternative measurement of static draught (fore and aft) . 5
4.3.4 Alternative measurement of water depth . 5
5 Measurement procedures and alternatives . 5
5.1 General . 5
5.2 Data acquisition . 5
5.3 Data storage . 6
5.4 Data preparation . 6
5.4.1 General. 6
5.4.2 Alternative procedure for expected speed calculation . 6
6 Calculation of performance indicators (PIs) . 9
6.1 General . 9
6.2 Definition of performance indicators . 9
6.3 Calculation of performance indicators . 9
6.3.1 General. 9
6.3.2 Determination of reference conditions . 9
6.3.3 Establishment of reference period and evaluation, and alternative
durations of reference and evaluation periods .10
6.3.4 Extraction of subsets of performance values from the complete set with
performance indicators that fulfil reference conditions for reference
periode(s) and evaluation period .10
6.3.5 Calculation of the PI .10
7 Accuracy of the performance indicators (PIs) .11
7.1 General .11
7.2 Standard combinations or primary parameters, secondary parameters and
measurement procedure details .11
7.3 Estimations of the uncertainty in the period average performance value .11
7.4 Calculating the performance indicator and estimating the accuracy of the
performance indicator.13
Bibliography .15
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ISO 19030-3:2016(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,
as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 8, Ships and marine technology, Subcommittee
SC 2, Marine environment protection.
A list of part of the ISO 19030 series can be found on the ISO website.
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ISO 19030-3:2016(E)

Introduction
Hull and propeller performance refers to the relationship between the condition of a ship’s underwater
hull and propeller and the power required to move the ship through water at a given speed.
Measurements of changes in ship specific hull and propeller performance over time make it possible
to indicate the impact of hull and propeller maintenance, repair and retrofit activities on the overall
energy efficiency of the ship in question.
The aim of this document is to prescribe practical methods for measuring changes in ship specific hull
and propeller performance and to define a set of relevant performance indicators for hull and propeller
maintenance, repair, retrofit activities. The methods are not intended for comparing the performance
of ships of different types and sizes (including sister ships) nor to be used in a regulatory framework.
This document consists of three parts.
— ISO 19030-1 outlines general principles for how to measure changes in hull and propeller performance
and defines a set of performance indicators for hull and propeller maintenance, repair and retrofit
activities.
— ISO 19030-2 defines the default method for measuring changes in hull and propeller performance
and for calculating the performance indicators. It also provides guidance on the expected accuracy
of each performance indicator.
— ISO 19030-3 outlines alternatives to the default method. Some will result in lower overall accuracy
but increase applicability of the standard. Others may result in same or higher overall accuracy but
includes elements which are not yet broadly used in commercial shipping.
The general principles outlined, and methods defined, in this document are based on measurement
equipment, information, procedures and methodologies which are generally available and
internationally recognized.
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INTERNATIONAL STANDARD ISO 19030-3:2016(E)
Ships and marine technology — Measurement of changes
in hull and propeller performance —
Part 3:
Alternative methods
1 Scope
This document outlines alternatives to the default method. Some will result in lower overall accuracy
but increase applicability of the standard. Others can result in same or higher overall accuracy but
includes elements which are not yet broadly used in commercial shipping.
The general principles outlined and performance indicators defined are applicable to all ship types
driven by conventional fixed pitch propellers, where the objective is to compare the hull and propeller
performance of the same ship to itself over time.
This document presents alternatives to measurement parameters (primary and then secondary) in
Clause 4, then alternatives to measurement procedures (including alternative reference and evaluation
periods) in Clause 5, describes the calculation of performance indicators in Clause 6, and finally the
estimation of performance indicator accuracy in Clause 7. The structure used duplicates the structure
of ISO 19030-2 to facilitate cross-reference between the two documents.
NOTE Support for additional configurations (e.g. variable pitch propellers) will, if justified, be included in
later revisions of this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3046-1, Reciprocating internal combustion engines — Performance — Part 1: Declarations of power, fuel
and lubricating oil consumptions, and test methods — Additional requirements for engines for general use
ISO 19030-1:2016, Ships and marine technology — Measurement of changes in hull and propeller
performance — Part 1: General principles
ISO 19030-2:2016, Ships and marine technology — Measurement of changes in hull and propeller
performance — Part 2: Default method
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 19030-1 and ISO 19030-2 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
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ISO 19030-3:2016(E)

4 Measurement parameters and alternatives
4.1 General
This clause explores alternatives to the primary and secondary measurement parameters defined for
the default method in ISO 19030-2. Whether using ISO 19030-2 or ISO 19030-3 (method alternatives),
in all instances, any instruments, automated equipment and sensors used shall be installed, maintained
and calibrated in accordance with the specification in ISO 19030-2:2016, 4.3.
4.2 Proxy for the primary measurement parameters
4.2.1 General
Hull and propeller performance as defined in ISO 19030-1:2016, 4.1 gives measurements of ship speed
through water and of power delivered to the propeller as the two primary measurement parameters.
ISO 19030-2:2016, Clause 4, defines minimum sensor requirements for these two parameters.
If the primary measurement parameters cannot be measured or the minimum sensor requirements
cannot be met, proxies can be used to approximate the parameters. As compared with the default
method, this will generally result in reduced accuracy. Table 1 summarises relevant proxies. 4.2 and
4.3 describe the proxies and estimate impact on accuracy. Speed data should be measured in m/s or
converted from knots to m/s using the conversion factor 1 knot = 0,514 4 m/s.
Table 1 — Sensor proxies for the primary measurement parameters
Parameter Proxy Measurement approach Unit
Speed through Speed Over Ground (SOG) Calculate SOG from GPS/navigation (m/s)
water system
Delivered power Alternative methods for estimat- Alternatives to ISO 19030-2:2016, (kW)
ing of delivered power (other than Annex B and Annex C approach
ISO 19030-2:2016, Annex B and
Annex C)
4.2.2 Proxy for speed through water measurement (speed over ground measurement)
4.2.2.1 General
It is possible to approximate a ship’s speed through water using speed over ground measurements.
Speed over ground measurements are typically directly available as, or can be calculated based
on information from, the GPS or navigation system. Using speed over ground as a proxy introduces
an uncertainty due to the influence of currents. This uncertainty will affect all ships, but to varying
extents depending on the area of operation and the ship’s frequency of encountering current speeds
with a similar magnitude to the ship’s speed through the water (e.g. current speed greater than 10 % of
the ship’s speed through the water). The impact of the uncertainty associated with the use of this proxy
is estimated and discussed in ISO 19030-1:2016, Annex A.
vv−
me
V =⋅100 (1)
d
v
e
where
V is the percentage speed loss;
d
v is the measured speed through water;
m
v is the expected speed through water.
e
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ISO 19030-3:2016(E)

When used as a proxy, speed over ground is a direct substitution for the measured speed (V ) through
m
water (in m/s) as defined in ISO 19030-2:2016, 5.4.7.2 and Formula (3) and in Formula (1).
4.2.2.2 Procedure for calculating the average speed over ground
The vessel’s speed over ground is a key quantity for measuring the changes in hull and propeller
performance. This data should be as accurate and precise as is practical.
When automatic recording systems for the vessel’s speed over ground are not available, alternative
methods to measure, calculate, and record the speed over ground are required.
When manual readings are required, the interval between measurements should be maintained as
much as is practical.
When a calculation of distance travelled per period of time is used, it is important to consider how the
distance travelled is measured and the method used shall be clearly documented. To ensure minimum
uncertainty of the performance value, speed and draught shall be kept approximately constant over the
period of time used to determine speed.
A clear procedure shall be documented to ensure that measurements and calculations are consistently
performed.
4.2.3 Proxy for delivered power (Alternative methods for estimating delivered power other
than ISO 19030-2:2016, Annex B and Annex C)
4.2.3.1 General
As one of the default methods for estimating delivered power, ISO 19030-2:2016, Annex B describes an
approach for estimating delivered power from fuel consumption data, using mass or volumetric flow
meters. This alternative considers situations where mass or volumetric flow meter data is not available.
This alternative method assumes a conventional propulsion system of a two-stroke main engine
directly coupled to a propeller (no gearbox), and without a shaft generator (power take-off). The
fuel consumption shall be measured for the main engine alone and shall not include consumption by
auxiliaries, boilers or returns.
The average delivered power over each sample’s period is calculated using Formula (2), which is the
same as ISO 19030-2:2016, Formula (C.1):
 
LCV
Pf=×M (2)
 
BFOC
42,7
 
where
M is the mass of consumed fuel oil by main engine (kg/h);
FOC
LCV is the lower calorific value of fuel oil (MJ/kg);
f is the SFOC reference curve.
In addition to the uncertainty inherent in any sensors, use of this proxy can introduce considerable
additional uncertainty. This is mainly due to the influence of changes in fuel quality, the accuracy of
the fuel mass measurement (see the section below for greater detail), and the influence of changes in
SFOC over time on account of engine degradation, all of which it is difficult to control for. The impact of
the uncertainty associated with the use of this proxy is estimated and discussed in ISO 19030-1:2016,
Annex A.
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ISO 19030-3:2016(E)

4.2.3.2 Obtaining the mass of fuel consumed (M ) and estimating the uncertainty in the
FOC
quantification of mass of fuel consumed
When automated systems are not available to automatically measure fuel consumed, alternative
methods can be considered. The choice of method will depend on the available equipment installed on
the vessel.
When manual readings are required, either by physical sounding of tanks or by taking manual
meter readings, the interval between measurements shall be maintained as much as is practical,
with a frequency no less than daily, and with the effect of any time zone changes accounted for when
calculating average parameters.
Any meters used for taking measurements shall be properly maintained, and their accuracy ensured
with periodic testing and calibration.
When manually sounding tanks, it is important to consider the trim and list of the vessel. A consistent,
documented process for taking accurate physical soundings of the tanks shall be used.
For both volumetric flow meters and sounding measurements, corrections shall be applied for
temperature and density. This shall follow the correction procedure specified in ISO 19030-2:2016,
Annex C.
Sources of uncertainty associated with obtaining measurements of the mass of fuel consumed by tank
soundings and flow meters, respectively, include the following:
— measurement errors due to ship motions, trim and/or list, errors due to manual recording or
calculation of total fuel consumed, errors due to the timings at which different tanks are sounded,
errors due to the inclusion of waste (sludge) in measured fuel consumption, uncertainty in the
dimensions of the tank and errors in the temperature and density measurement and correction
calculation;
— measurement uncertainty of the flow meter and errors in the temperature and density measurement
and correction calculation;
— error propagation due to calculating fuel consumption from differences of inflow and outflow of fuel.
4.2.3.3 Estimating the SFOC
If available, the SFOC curve used shall be based on actual shop tests of the specific engine in question
covering all relevant engine output ranges and shall be corrected for environmental factors as per
ISO 3046-1, and for a normal fuel of 42 700 kJ/kg.
If actual shop tests of the specific engine in question covering all relevant engine output ranges are
not available, then the SFOC characteristic for a given engine type shall be obtained from the engine
manufacturer.
4.3 Secondary measurement parameters and alternatives
4.3.1 General
For the isolation of comparable reference conditions and for the filtering and normalization procedures,
both environmental factors and the ship’s operational profile shall be measured. To this effect,
ISO 19030-2:2016, 4.3 defines a number of secondary measurement parameters and minimum sensor
requirements for each of these parameters.
If these parameters cannot be measured or the minimum sensor requirements cannot be met, proxies
can be used to isolate comparable reference conditions and to enable filtering and normalization
procedures.
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ISO 19030-3:2016(E)

In some cases, instead of adopting a proxy, one may have to modify the reference condition criterion
(defined in ISO 19030-2:2016, 6.3.2) or modify the analysis procedure; any such modification shall be
fully and transparently documented and justified.
Table 2 — Sensor proxies for normalization procedures and reference condition criterion
Alternative measurement
Wind speed Anemometer with lower accuracy than as specified in ISO 19030-2
Draught (fore and aft) Observed directly or derived from observed draught (fore and aft) in port
Water depth Calculated from electronic nautical charts and the ship track from (D)GPS
Rudder angle None
4.3.2 Alternative measurement of wind speed
If measurements of the relative wind speed according to the sensor accuracy requirement specified in
ISO 19030-2 are not available, lower accuracy sensors may be used instead. In all other respects, the
procedure specified in ISO 19030-2 shall be followed.
When manual readings are required, the interval between measurements shall be maintained as
much as is practical, with a frequency no less than daily and with the effect of any time zone changes
accounted for. These recordings shall reflect representative wind conditions for the period in question.
4.3.3 Alternative measurement of static draught (fore and aft)
The vessel’s draught at sea can be recorded from the loading computer. Input shall reflect the vessel’s
condition at the beginning of sea passage, or may be derived from observed draught and trim in port.
When manual recording methods are used, the interval between measurements shall be maintained
as much as is practical. If there is a significant change in displacement, then draught values shall be
updated to reflect actual loading conditions.
Draught marks, when used, can be hard to read due to poor lighting, fading coatings, hull fouling, and
conditions other than calm. A clear procedure shall be documented to ensure that personnel take
accurate readings.
The impact of the uncertainty associated with the use of this proxy is estimated and discussed in
ISO 19030-1:2016, Annex A.
4.3.4 Alternative measurement of water depth
In the event that automated logging of the water depth is not available, whenever the ship is operating in
water depths less than 100 m, this data shall be obtained from electronic nautical charts and recorded
alongside other secondary data.
5 Measurement procedures and alternatives
5.1 General
This clause discusses how measurement data is to be acquired, stored and prepared.
5.2 Data acquisition
ISO 19030-2:2016, 5.2, specifies that the following data shall be recorded simultaneously at a frequency
of 1 signal every 15 s (0,07 Hz) or above and collected by a data acquisition system (e.g. a data logger). If
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ISO 19030-3:2016(E)

a system for data collection at this frequency is not available, this document permits the measurements
described in Clause 4 to be recorded less frequently (e.g. as noon data) with the following specifications:
— the data sampling rate shall remain unchanged over the full measurement period (reference period
and evaluation period), except for changes created by time zone change (see below);
— primary measurement parameters (speed, power from either shaft torque and rpm or fuel
consumption) shall be averaged over the period;
— secondary measurement parameters shall, as much as possible, be collected at the same sampling
rate as the primary measurement parameters, or no less frequently than 1 signal per day. With the
exception of wind and draught, these values shall be short-term average values (e.g. averages over
1 min) taken at the point in time the observation is obtained.
NOTE 1 It is often the case that the daily report is filed at noon local time. If a ship is changing time zone
during the voyage, this will mean that occasionally, the time period between a daily noon report is slightly more
or less than 24 h (e.g. typically 1 h). This variation will have a negligible impact on the accuracy of the estimation
and can be tolerated.
To guide the interpretation of performance measurements, the influence of two different sampling
and averaging periods (frequency according to specification in ISO 19030-2:2016, Table 2, and daily
frequency) on performance value uncertainty is addressed in Clause 7.
If data cannot be automatically collected, data shall be collected manually. This introduces an
uncertainty partially due to the increased probability of human error over error probability in
automated data collection systems, but also due to the necessity of reducing the sampling frequency.
NOTE 2 Lower frequency of data collection increases uncertainty in many ways. It reduces the number of
data points available from which the average performance values are calculated, and it increases the uncertainty
effects related to the use of primary parameter average values (e.g. the use of an average speed and power if
both experience a significant variation due to changes in operation over the time period of the sample). Both
of these effects on performance indicator uncertainty are incorporated in the treatment of uncertainty in
ISO 19030-1:2016, Annex A.
5.3 Data storage
Data should be stored according to the procedure in ISO 19030-2:2016, 5.3.
5.4 Data preparation
5.4.1 General
Data shall generally be prepared according to ISO 19030-2:2016, 5.4.
Where the frequency of acquisition is one measurement per ten minute period or higher, data shall
be filtered and validated accord
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