Ships and marine technology -- Measurement of changes in hull and propeller performance

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

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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
---------------------- Page: 1 ----------------------
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
---------------------- Page: 2 ----------------------
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

© ISO 2016 – All rights reserved iii
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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.
iv © ISO 2016 – All rights reserved
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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.
© ISO 2016 – All rights reserved v
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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
© ISO 2016 – All rights reserved 1
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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−
V =⋅100 (1)
where
V is the percentage speed loss;
v is the measured speed through water;
v is the expected speed through water.
2 © ISO 2016 – All rights reserved
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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

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.
© ISO 2016 – All rights reserved 3
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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.
4 © ISO 2016 – All rights reserved
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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

© ISO 2016 – All rights reserved 5
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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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