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

ISO 19030-2:2016 defines the default method for measuring changes in hull and propeller performance and calculating a set of basic performance indicators. Finally, it provides guidance on the expected accuracy of each performance indicator. ISO 19030-2:2016 is applicable for commercial ship types of the displacement type driven by conventional fixed pitch propeller(s) where the objective is to compare the hull and propeller performance of the same ship to itself over time. 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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Publication Date
15-Nov-2016
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9020 - International Standard under periodical review
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15-Oct-2021
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INTERNATIONAL ISO
STANDARD 19030-2
First edition
2016-11-15
Ships and marine technology —
Measurement of changes in hull and
propeller performance —
Part 2:
Default method
Navires et technologie maritime — Mesurage de la variation de
performance de la coque et de l’hélice —
Partie 2: Méthode par défaut
Reference number
ISO 19030-2:2016(E)
ISO 2016
---------------------- Page: 1 ----------------------
ISO 19030-2:2016(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland

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ii © ISO 2016 – All rights reserved
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ISO 19030-2:2016(E)
Contents Page

Foreword ..........................................................................................................................................................................................................................................v

Introduction ................................................................................................................................................................................................................................vi

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Measurement parameters .......................................................................................................................................................................... 2

4.1 General ........................................................................................................................................................................................................... 2

4.2 Primary parameters ........................................................................................................................................................................... 2

4.3 Secondary parameters ..................................................................................................................................................................... 3

4.4 Sensor installation, maintenance and calibration .................................................................................................... 3

4.5 External information.......................................................................................................................................................................... 4

5 Measurement procedures ........................................................................................................................................................................... 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 Data preparation frequency ................................................................................................................................... 7

5.4.3 Data retrieval ...................................................................................................................................................................... 7

5.4.4 Data compilation .............................................................................................................................................................. 7

5.4.5 Data filtering and validation .................................................................................................................................. 8

5.4.6 Correction for environmental factors ............................................................................................................ 8

5.4.7 Calculation of performance values (PVs) .................................................................................................... 8

6 Calculation of performance indicators (PIs) ........................................................................................................................... 9

6.1 General ........................................................................................................................................................................................................... 9

6.2 Definition of PIs .................................................................................................................................................................................... 9

6.3 Calculation of PIs ................................................................................................................................................................................... 9

6.3.1 General...................................................................................................................................................................................... 9

6.3.2 Determination of reference conditions .....................................................................................................10

6.3.3 Establishment of reference period and evaluation period .......................................................10

6.3.4 Extraction of subsets of PVs from the complete set with PVs that fulfil
reference conditions for reference conditions for reference period(s) and

evaluation period .........................................................................................................................................................11

6.3.5 Calculation of the PI ...................................................................................................................................................11

7 Accuracy of PIs .....................................................................................................................................................................................................12

7.1 General ........................................................................................................................................................................................................12

7.2 Guidance on the expected accuracy of PIs....................................................................................................................12

Annex A (informative) Process of this document .................................................................................................................................14

Annex B (normative) Approximating delivered power based on calculations of shaft power .............15

Annex C (normative) Approximating delivered power based on calculations of brake power ............16

Annex D (informative) SFOC reference curve ...........................................................................................................................................19

Annex E (normative) Calculation of true wind speed and direction ................................................................................21

Annex F (informative) Procedure to obtain ship specific power-speed-draught-trim databases .....24

Annex G (normative) Correction for wind resistance ......................................................................................................................25

Annex H (informative) Protocol to export data from data logger .......................................................................................27

Annex I (normative) Outlier detection ............................................................................................................................................................32

Annex J (normative) Validation...............................................................................................................................................................................34

© ISO 2016 – All rights reserved iii
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ISO 19030-2:2016(E)

Annex K (informative) Method for calculating power performance values (PPV) and power

performance indicators (PPI) ..............................................................................................................................................................35

Bibliography .............................................................................................................................................................................................................................37

iv © ISO 2016 – All rights reserved
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ISO 19030-2:2016(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 all parts in the ISO 19030 series can be found on the ISO website.
© ISO 2016 – All rights reserved v
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ISO 19030-2:2016(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 and 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

include 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.

Clause 4 defines the primary and secondary parameters as well as external information needed.

Clause 5 defines how measurement data are to be acquired, stored and prepared. Clause 6 defines how

the performance indicators are to be calculated. Clause 7 provides guidance on the expected accuracy

of each performance indicator.
Annex A illustrates the process in terms of a flow chart.
vi © ISO 2016 – All rights reserved
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INTERNATIONAL STANDARD ISO 19030-2:2016(E)
Ships and marine technology — Measurement of changes
in hull and propeller performance —
Part 2:
Default method
1 Scope

This document defines the default method for measuring changes in hull and propeller performance

and calculating a set of basic performance indicators. Finally, it provides guidance on the expected

accuracy of each performance indicator.

This document is applicable for commercial ship types of the displacement type driven by conventional

fixed pitch propeller(s) where the objective is to compare the hull and propeller performance of the

same ship to itself over time.

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 15016:2015, Ships and marine technology — Guidelines for the assessment of speed and power

performance by analysis of speed trial data

ISO 19030-1:2016, Ships and marine technology — Measurement of changes in hull and propeller

performance — Part 1: General principles
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
3.1
changes in hull and propeller performance

changes in delivered power required to move the ship through water at a given speed or equivalently

changes in speed through water at a given delivered power, given unchanged transmission efficiency,

and the same environmental conditions and operational profile
3.2
reference period
period in time of a certain length used to establish a baseline
© ISO 2016 – All rights reserved 1
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ISO 19030-2:2016(E)
3.3
evaluation period

period in time after the reference period (3.2), used for comparing with the baseline

3.4
reference conditions

set of comparable conditions of environmental and/or operational factors or a set of ranges of such

conditions
3.5
tabular format

formatting data in rows and columns, to break down specific data into a quickly scanable layout

3.6
unique identifier

identifier which is guaranteed to be unique among all identifiers used for those objects and for a

specific purpose
4 Measurement parameters
4.1 General

This clause describes the primary and secondary parameters for measuring changes in hull and

propeller performance.
4.2 Primary parameters

In ISO 19030-1, ship speed through water, V, and delivered power, P , are defined as the two primary

measurement parameters for measuring changes in hull and propeller performance.

Ship speed through water shall be measured directly, in knots, using a speed log with a minimum

sensor accuracy of ±1 %, at 1σ of the speed of the ship, or ±0,1 knots, at 1σ (both as specified by the

sensor manufacturer) whichever is greater.

NOTE Since the overall accuracy associated with measurements of hull and propeller performance is highly

sensitive to uncertainties in the measurement of speed, this requirement is intentionally stricter than current

SOLAS requirements.

Delivered power shall be approximated based on calculations of shaft power, P , from measurements of

shaft torque and shaft revolutions following Annex B or, if a torque meter with required signal quality

is not available and the conditions defined in Annex C are fulfilled, shall be based on calculations of

brake power, P , from an engine-specific SFOC (specific fuel oil consumption) reference curve defined

in Annex D, continuous measurements of fuel flow and temperature and bunker analysis data (calorific

value, density and density change rate for the fuel being consumed).

The approaches to calculating shaft power and brake power, as well as minimum required sensors and

sensor accuracies for each, are specified in Annex B and Annex C, respectively.

The same approach to approximating delivered power shall be used throughout both the reference and

evaluation periods.
1) Confidence interval of 66 %.
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ISO 19030-2:2016(E)
4.3 Secondary parameters

For the isolation of comparable reference conditions and as input to data preparation (filtering,

normalization), both environmental factors and the ship’s operational profile shall be measured.

NOTE Not all factors influencing measured performance are addressed in this document, e.g. frequency of

rudder movement or side current effects. Future revisions of this document may address such factors.

The minimum sensor requirements for the secondary measurement parameters are defined in Table 1.

Table 1 — Minimum sensor requirements, secondary measurement parameters
Parameter Acceptable measurement device/source Unit
Relative wind speed and Ship anemometer
direction measured at the height m/s, °
— minimum sensor accuracy of ±1 m/s, ±5°
of the anemometer
Speed over ground (D) GPS knots
Ship heading Gyro compass, or compass — DGPS °
Shaft revolutions Pick-up, optical sensor, ship revs counter
rev/min
with minimum sensor accuracy of ±0,5 %, 1σ
Static draught fore and aft Information from loading or stability computer or
equivalent sources for static draught.
NOTE Preference for observed draught, when available.
Water depth Ship echo sounder with minimum sensor accuracy of:
— ±0,5 m on the 20 m range scale, respectively;
— ±5 m on the 200 m range scale;
— ±2,5 % of the indicated depth, whichever is
greater.
Rudder angle Rudder angle indicator
— minimum sensor accuracy of ±1°
Seawater temperature Thermometer °C
Ambient air temperature Thermometer °C
Air pressure Barometer Pa
Minimum sensor accuracy refers to the sensor manufacturer’s specified accuracy.

For rudder angle, the following convention shall be followed: values shall range from −180° to 180°,

with 0° meaning amidship, positive values meaning starboard.

True wind is calculated from relative wind at the height of the anemometer according to the procedures

in Annex E. Wind direction and ship heading are defined in Figure E.2.

If ambient air temperature is not measured, a constant air temperature value of 15 °C shall be used.

If air pressure is not measured, a constant air pressure value of 101,325 kPa (1 atm) shall be used.

For vessels with twin screws, shaft revolutions shall be measured on both shafts.

It is recommended to use the same sensor type on both shafts.
4.4 Sensor installation, maintenance and calibration

All sensors shall be installed, maintained and calibrated as per manufacturer specification and as per

the requirements of the ship owner’s planned maintenance system. The same set of sensors and the

same sensor settings shall be used in the reference period and the evaluation period. Furthermore, data

© ISO 2016 – All rights reserved 3
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ISO 19030-2:2016(E)

shall be logged with the same precision over the reference and evaluation period and to at least three

significant figures for all parameters (except time and date).

It is underlined that speed log recalibration shall only be done according to the manufacturer

specification, as the accuracy of the hull and propeller performance indicator depends critically on the

correct functioning of the speed through water sensor.
4.5 External information

Speed-power data shall be available for the vessel in question. These may originate from the following

power estimation approaches:

— from full-scale speed trials that were conducted and analysed according to ISO 15016;

— from towing tank tests having demonstrated compliance with international standards of quality;

— from computational fluid dynamics (CFD) simulations conducted and analysed following generally

accepted state-of-the-art procedures, e.g. those recommended by the International Towing Tank

Conference (ITTC);
It has to be documented how the speed-power data have been obtained.

Displacement tables and/or formulae for the vessel in question shall be made available (needed to

convert measured draught and trim into displacement).

The speed-power data have to cover the actual operational speed-power range of the vessel in question

and it shall be available for the actual operational loading conditions (draught, trim) of the vessel in

question. Data from the same approach shall be used consistently over the whole operational range of,

and over both reference and evaluation periods for, the vessel in question.

If a significant change in the operational behaviour of the vessel occurs, e.g. by following a slow-steaming

regime during one period but not during another period or by starting to use trim optimization, high

resolution speed-power-draught-trim data shall be used to ensure that the estimated level of accuracy

(see 7.2) is maintained. Annex F describes a procedure on how to obtain high-resolution speed-power-

draught-trim databases.

High resolution speed-power-draught-trim data is generally recommended in case of high variability in

the operational parameters.

If speed-power reference data are not available for the actual operational speed-power range of the

vessel or for the actual operational loading range of the vessel, additional speed-power data have to be

estimated as follows.
If speed-power reference data are available for
— displacement values within ±5 % of the actual displacement, and

— for trim values within ±0,2 % of the length between perpendiculars of the actual trim of the vessel,

the speed-power reference data for the displacement closest to the actual displacement shall be used as

reference data and remaining displacement variations shall be corrected for by following the Admiralty

formula [see Formula (1)]:
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ISO 19030-2:2016(E)
13/
23/
 
 
VV= (1)
 23/ 
 2 
where
V is the speed at measured displacement;
V is the speed at reference displacement;
Δ is the measured displacement;
Δ is the reference displacement.

Otherwise, additional speed-power data shall be estimated by applying the above specified power

estimation approaches. It has to be documented how the data have been obtained.

If speed-power reference data are not available for the actual operational speed-power range of the

vessel or the actual loading conditions of the vessel, additional speed trials, towing tank tests or CFD

calculations should be performed to obtain additional speed-power data. Alternative approaches are

described in ISO 19030-3:2016, 5.4.2.

For the correction for wind resistance (as detailed in Annex G) and the true wind speed and direction

(as detailed in Annex E), the following quantities are needed for one reference condition (typically

design condition):

— transverse projected area of windage area and height of its (estimated) centroid above water level;

— wind resistance coefficients based on transverse projected area;

— anemometer height above sea level at reference condition (typically design condition).

As basis for the correction, wind resistance coefficients from wind tunnel tests of the vessel in question

shall be used. If these are not available, wind resistance coefficients for the vessel type in question shall

be used following ISO 15016.

Ship width is needed for wind correction and in the filtering for reference conditions.

5 Measurement procedures
5.1 General

This clause discusses how measurement data are to be acquired, stored and prepared.

5.2 Data acquisition

Data shall be automatically and continuously collected by the data acquisition system (e.g. a data logger)

as follows in Table 2.
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ISO 19030-2:2016(E)
Table 2 — Minimum data acquisition rates
Parameter Minimum data acquisition rate
Primary parameters Vessel speed through water Once every 15 s (0,07 Hz)
Delivered power Same as for vessel speed and same time stamp as
vessel speed
Secondary parameters Shaft revolutions Once every 15 s (0,07 Hz)
Relative wind Once every 15 s (0,07 Hz)
speed/direction
Speed over ground and ship Once every 15 s (0,07 Hz)
heading
Rudder angle Once every 15 s (0,07 Hz)
Water depth Once every 15 s (0,07 Hz)
Static draught fore and aft Whenever loading condition changes
Water temperature Once every 15 s (0,07 Hz)

The sensor measurements needed to estimate delivered power by either Annex B or Annex C shall be logged at the

minimum acquisition rate for the primary parameters and with the same time stamp.

The data sampling rate shall remain unchanged over the full measurement period (reference period

and evaluation period).

NOTE Over short periods of time, the data sampling rate may coincide with the frequency of a natural

phenomenon for the vessel in question (e.g. wave encounter frequency) and thereby influencing the accuracy of

associated data point.
5.3 Data storage

All data collected over the measurement period shall be stored in the data acquisition system. All data

shall be stored as raw data along with time stamps as time offsets from universal time coordinated

(UTC) indicating the point in time the data were collected.

It is recommended that data shall be backed up at an appropriate backup facility at a minimum of once

every month. If the data acquisition system is kept on board the vessel, it is recommended that the

backup facility is located elsewhere.

At any one time it shall be possible for the owner of the data to retrieve all data stored in the data

acquisition system or at the backup facility as raw data along with the time stamps. The data shall be

retrievable in a commonly used electronic format.

It is recommended that all collected data be stored in the data acquisition system and/or at the backup

facility at least over the remaining life of the ship in question or as determined by the use of the

standard.
NOTE Annex H recommends a format of exporting stored data.
5.4 Data preparation
5.4.1 General

Data preparation involves retrieving, compiling, filtering and validating collected data in order to

provide a structure, format and quality that is suitable for further processing and in order to enable

corrective measures if the collected data are found to be invalid (e.g. on account of sensor drift). It

furthermore comp
...

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