SIST EN IEC 62097:2019

SLOVENSKI STANDARD
01-julij-2019
Nadomešča:
SIST EN 62097:2010
Vodni stroji, radialni in aksialni - Metodologija prenosa uspešnosti z modela na
prototip (IEC 62097:2019)
Hydraulic machines, radial and axial - Methodology for performance transposition from
model to prototype (IEC 62097:2019)
Hydraulische Maschinen, radial und axial - Leistungsumrechnung vom Modell zum
Prototyp (IEC 62097:2019)
Machines hydrauliques, radiales et axiales - Méthode de conversion des performances
du modèle au prototype (IEC 62097:2019)
Ta slovenski standard je istoveten z: EN IEC 62097:2019
ICS:
27.140 Vodna energija Hydraulic energy engineering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 62097

NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2019
ICS 27.140 Supersedes EN 62097:2009
English Version
Hydraulic machines, radial and axial - Methodology for
performance transposition from model to prototype
(IEC 62097:2019)
Machines hydrauliques, radiales et axiales - Méthodologie Hydraulische Maschinen, radial und axial -
de transposition des performances du modèle au prototype Leistungsumrechnung vom Modell zum Prototyp
(IEC 62097:2019) (IEC 62097:2019)
This European Standard was approved by CENELEC on 2019-02-12. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62097:2019 E
European foreword
The text of document 4/359/FDIS, future edition 2 of IEC 62097, prepared by IEC/TC 4 "Hydraulic
turbines" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2019-11-12
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-02-12
document have to be withdrawn
This document supersedes EN 62097:2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 62097:2019 was approved by CENELEC as a European
Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
ISO 4287 NOTE Harmonized as EN ISO 4287
ISO 4288 NOTE Harmonized as EN ISO 4288

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60193 -  Hydraulic turbines, storage pumps and EN 60193 -
pump-turbines - Model acceptance tests

IEC 62097 ®
Edition 2.0 2019-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Hydraulic machines, radial and axial – Methodology for performance

transposition from model to prototype

Machines hydrauliques, radiales et axiales – Méthodologie de transposition des

performances du modèle au prototype

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.140 ISBN 978-2-8322-6277-1

– 2 – IEC 62097:2019  IEC 2019
CONTENTS
FOREWORD . 7
INTRODUCTION . 10
0.1 General remarks . 10
0.2 Basic features . 11
1 Scope . 12
2 Normative references . 12
3 Terms, definitions, units, subscripts and symbols . 12
3.1 Terms and definitions. 12
3.2 List of definitions by topic . 13
3.3 Subscripts and symbols . 14
3.4 Geometric terms . 15
3.5 Physical quantities and properties . 15
3.6 Discharge, velocity and speed terms . 16
3.7 Pressure terms . 16
3.8 Specific energy terms . 16
3.9 Head terms . 17
3.10 Power and torque terms . 18
3.11 Efficiency terms . 19
3.12 Fluid dynamics and scaling terms . 20
3.13 Dimensionless terms . 20
4 Scale-effect formula . 22
4.1 General . 22
4.1.1 Scalable losses . 22
4.1.2 Basic formulae of the scale effect on hydrodynamic friction losses . 23
4.2 Specific hydraulic energy efficiency . 25
4.2.1 General . 25
4.2.2 Radial flow machines . 26
4.2.3 Axial flow machines . 26
4.3 Volumetric efficiency . 26
4.4 Power efficiency (disk friction) . 27
4.4.1 Radial flow machines . 27
4.4.2 Axial flow machines . 27
5 Surface roughness of model and prototype . 28
5.1 General . 28
5.2 Measurement of surface roughness . 28
5.2.1 Procedure . 28
5.2.2 Roughness of model and prototype . 29
5.2.3 Measurement of very rough surfaces . 30
5.3 Surface roughness ranges . 30
6 Standardized values of scalable losses and pertinent parameters . 32
6.1 General . 32
6.2 Specific speed . 33
6.3 Parameters for specific hydraulic energy efficiency transposition . 33
6.3.1 General . 33
6.3.2 Francis turbines . 33
6.3.3 Pump-turbines . 34

IEC 62097:2019  IEC 2019 – 3 –
6.3.4 Axial flow machines . 34
6.4 Parameters for power efficiency (disk friction) transposition . 35
6.4.1 Francis turbines . 35
6.4.2 Pump-turbines . 35
6.4.3 Axial flow machines . 35
7 Transposition to prototype . 36
7.1 General . 36
7.2 Assumed maximum hydraulic efficiency . 37
7.3 Hydraulic efficiency . 38
7.4 Specific hydraulic energy . 39
7.4.1 Turbine operation . 39
7.4.2 Pump operation . 39
7.5 Discharge . 40
7.5.1 Turbine operation . 40
7.5.2 Pump operation . 40
7.6 Torque . 40
7.6.1 Turbine operation . 40
7.6.2 Pump operation . 40
7.7 Power . 41
7.7.1 Turbine operation . 41
7.7.2 Pump operation . 41
8 Calculation procedure . 41
8.1 General . 41
8.2 Reference model. 42
8.3 Comparison of different models . 42
8.4 Normalization procedure of the test data: Step 1 . 42
8.5 Prototype transposition procedure: Step 2 . 44
8.6 Alternative one step method for the optimum point . 46
8.7 equired input data . 48
Annex A (informative) Basic formulae and their approximation . 50
A.1 Basic concept of loss structure and scale effect . 50
A.1.1 General . 50
A.1.2 Loss structure and efficiency components . 50
A.1.3 Homologous operating condition . 52
A.1.4 Shifting of performance [6] . 53
A.1.5 Scalable losses . 54
A.2 Derivation of the scale effect formulae and the approximation introduced for
simplifications . 55
A.2.1 Scalable loss ratio in specific hydraulic energy δ and specific
E
hydraulic energy efficiency . 55
η
E
A.2.2 Transposition of specific hydraulic energy efficiency η . 56
E
η
A.2.3 Transposition of volumetric efficiency . 58
Q
η
A.2.4 Transposition of power efficiency (disk friction) . 59
T
Annex B (informative) Scale effect on specific hydraulic energy losses of radial flow
machines . 61
B.1 Scale effect on friction loss . 61
B.1.1 Scale effect on friction loss coefficient . 61

– 4 – IEC 62097:2019  IEC 2019
B.1.2 Relationship between sand roughness k and arithmetical mean
s
roughness Ra . 63
B.2 Componentwise transposition of specific hydraulic energy efficiency . 63
B.2.1 Friction loss coefficient of each component [9] . 63
B.2.2 Derivation of the scale effect formula for component wise transposition . 66
B.3 Standardized relative scalable hydraulic energy loss of radial flow machines . 67
B.3.1 Definition . 67
B.3.2 Standardized relative scalable hydraulic energy loss δ of Francis
E
turbine . 68
δ
B.3.3 Standardized relative scalable hydraulic energy loss of reversible
E
pump-turbine . 70
κ κ
B.4 Flow velocity factor and dimension factor of radial flow
uCO dCO
machines [9] . 71
B.4.1 Definition . 71
κ κ
B.4.2 and for Francis turbine . 71
uCO dCO
B.4.3 κ  and κ for pump-turbine . 73
uCO dCO
d
B.5 Standardized scalable loss index . 76
ECOref
B.5.1 Definition . 76
B.5.2 Standardized d and d for Francis turbine . 76
ECOref Eref
B.5.3 Standardized d and d for pump-turbine . 77
ECOref Eref
Annex C (informative) Scale effect on specific hydraulic energy losses of axial flow
machines [9] . 79
C.1 Scalable losses of axial flow machines . 79

C.2 Scale effect formula for runner blades [8] . 79
C.3 Scale effect formula for stationary parts . 80
C.4 Scale effect for other efficiency components . 81
C.4.1 Volumetric efficiency. 81
C.4.2 Power efficiency (disk friction) . 81
C.5 Scale effect of hydraulic efficiency . 81
C.6 Determination of δ of axial flow turbines . 81
ECOref
δ
C.7 Determination of of bulb turbines . 82
ECOref
d
C.8 Derivation of scalable hydraulic energy loss index, . 83
Eref
C.8.1 Scalable loss index for runner blades . 83
C.8.2 Scalable loss index for stationary parts . 83
C.9 Summary of the scale effect formula for axial flow machines . 84
Annex D (informative) Scale effect on disk friction loss . 85
D.1 Loss coefficient formula for disk friction . 85
D.2 Transposition formula for power efficiency . 86
κ d
D.3 Standardized dimension factor and disk friction loss index . 87
T Tref
D.3.1 Disk friction loss ratio δ . 87
Tref
D.3.2 Dimension factor of the disk κ . 88
T
D.3.3 Disk friction loss index d . 89
Tref
Annex E (informative) Comparison of IEC 60193 and IEC 62097 hydraulic efficiency
transposition methods for reaction machines . 91

IEC 62097:2019  IEC 2019 – 5 –
E.1 IEC 60193 transposition method . 91
E.1.1 Applications . 91
E.1.2 Limitations . 91
E.2 IEC 62097 transposition method . 91
E.2.1 Applications . 91
E.2.2 Limitations . 91
Annex F (informative) Leakage loss evaluation for non homologous seals . 93
F.1 Loss coefficient of runner seal . 93
∆η
F.2 General formula to obtain for non-homologous seal . 97
Q
F.3 Evaluation of scale effect in case of a homologous straight seal . 97
F.4 Straight seal with non-homologous radial clearance . 98
Annex G (normative) Guide for detailed calculations by means of the attached Excel
workbook . 100
G.1 Normalization of test data: Step 1 of the “2 step method” . 100
G.2 Prototype transposition: Step 2 of the “2 step method” . 101
G.3 Alternative one step method for the optimum point . 102
Annex H (informative) Example of a calculation with the attached Excel workbook . 104
H.1 Cover page . 104
H.2 Example of STEP 1 for a Pump-Turbine in Turbine Mode . 105
H.2.1 « Input Form » data sheet for step 1 . 105
H.2.2 Results for Step 1 . 107
H.3 Example of STEP 2 for a Pump-Turbine in Turbine Mode . 115
H.3.1 « Input Form » data sheet for step 2 . 115
H.3.2 Results for Step 2 . 117
Bibliography . 125

Figure 1 – Scale effect considering surface roughness . 24
Figure 2 – Impact of surface roughness on turbine efficiency and costs . 28
Figure 3 – Surface roughness regions for Francis runner blades . 31
Figure 4 – Surface roughness region for axial flow runner blade . 32
Figure 5 – Normalization of test data from Re to Re and Re to Re . 36
M M* M* P
i
Figure 6 – Reference Assumed maximum hydraulic efficiency . 38
Figure 7 – Calculation procedure: “Two step method”: First step – From model to
reference model . 43
Figure 8 – Calculation procedure: “Two step method”: Second step – From reference
model to prototype . 45
Figure 9 – Calculation procedure: Alternative one step method for the optimum point
from model to prototype . 47
Figure A.1 – Flux diagram for a turbine . 51
Figure A.2 – Flux diagram for a pump . 52
Figure B.1 – Loss coefficient versus Reynolds number and surface roughness . 62
Figure B.2 – Different characteristics of λ in transition zone . 62
Figure B.3 – Representative dimensions of component passages . 65
Figure B.4 – Standardized relative scalable hydraulic energy loss in each component
of Francis turbine . 69
Figure B.5 – Standardized relative scalable hydraulic energy loss in each component
of pump-turbine in turbine operation . 70

– 6 – IEC 62097:2019  IEC 2019
Figure B.6 – Standardized relative scalable hydraulic energy loss in each component
of pump-turbine in pump operation . 71
κ κ
Figure B.7 – and in each component of Francis turbine . 72
uCO dCO
κ κ
Figure B.8 – and in each component of pump-turbine in turbine operation . 74
uCO dCO
Figure B.9 – κ  and κ in each component of pump-turbine in pump operation . 75
uCO dCO
d d
Figure B.10 – Standardized and for Francis turbine . 76
ECOref Eref
d d
Figure B.11 – Standardized and for pump-turbine in turbine operation . 77
ECOref Eref
d d
Figure B.12 – Standardized and for pump-turbine in pump-operation . 78
ECOref Eref
Figure C 1 – δ for Kaplan turbines . 82
ECOref
δ
Figure D.1 – Disk friction loss reference ratio . 88
Tref
κ
Figure D.2 – Dimension factor . 89
T
Figure D.3 – Disk friction loss index d . 90
Tref
Figure F.1 – Examples of typical design of runner seals (crown side) . 95
Figure F.2 – Examples of typical design of runner seals (band side) . 96

Table 1 – Permissible deviation of the geometry of model seals from the prototype . 27
Table 2 – Recommended roughness range for the model . 30
Table 3 – Minimum recommended prototype roughness for new radial or diagonal
machines . 31
Table 4 – Maximum recommended prototype roughness for new radial or diagonal
machines . 31
Table 5 – Minimum recommended prototype roughness for new axial turbines . 32
Table 6 – Maximum recommended prototype roughness for new axial turbines . 32
Table 7 – Standardized scalable loss index d and standardized velocity factor
ECOref
κ for Francis turbines . 33
uCO
Table 8 – Standardized scalable loss index d and standardized velocity factor
ECOref
κ for pump-turbines in turbine operation . 34
uCO
Table 9 – Standardized scalable loss index d and standardized velocity factor
ECOref
κ for pump-turbines in pump operation . 34
uCO
Table 10 – Standardized scalable loss index d and velocity factor κ for
ECOref uCO
axial flow machines . 34
Table 11 – Calculation of η . 37
hAmaxMref
Table 12 – Reference roughness of the reference model, Ra . 42
COMref
Table 13 – Required input data for the calculation of the prototype performance . 48
Table A.1 – Definitions of scalable loss ratios . 56
Table A.2 – Definitions of transposition of specific energy . 57
Table A.3 – Definitions of transposition of volumetric efficiency . 58
Table A.4 – Definitions of power efficiency transposition terms . 59
d
EST
Table C.1 – Ratio of for Francis turbines and pump-tubines . 84
δ
EST
IEC 62097:2019  IEC 2019 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HYDRAULIC MACHINES, RADIAL AND AXIAL – METHODOLOGY FOR
PERFORMANCE TRANSPOSITION FROM MODEL TO PROTOTYPE

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62097 has been prepared by IEC technical committee 4: Hydraulic
turbines.
This second edition cancels and replaces the first edition published in 2009. This edition
constitutes an editorial and technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) In introduction, clarifications have been brought such as addition of a sentence which
declares the precedence of IEC 62097 over IEC 60193 if any mismatch is found between
them
b) In Clauses 3 and 4, corrections of the typographical errors
c) In Clause 3: changes to be in accordance with presentation of the terms and structure of
IEC 60193 (except for the water temperature)
d) In Clause 4:
– Deletion of the clause providing the direct step-up procedures for a whole turbine

– 8 – IEC 62097:2019  IEC 2019
– Introduction of a global view by using turbine A and turbine B instead of model turbine,
reference model turbine and prototype turbine
– Move of section dealing with “surface roughness of model and prototype” in a new
Clause 5
e) In Clause 5:
– Introduction of additional chapters to answer comments raised at the CDV stage and to
clarify the subject of surface roughness of model and prototype
– Introduction of new tables for minimum recommended prototype roughness for new
radial or diagonal machines and for new axial turbines
– Addition of the explanation about roughness measurement of heavily rusted surface
f) In Clause 7 (former Clause 6):
– Introduction of a new subclause for clarifications about the assumed maximum
hydraulic efficiency, η
hAmax
– Deletion of the requirement of mutual agreement for the application of the step-up
formula for very high efficiency machines exceeding η
hAmax
– Clarifications of the equations from 22 to 33 by doubling the equations for suiting the
“two step method”
g) In Clauses 6 and 7, correction of typographical errors
h) In Clause 8 (former Clause 7), introduction of new figures for clarifying the “2 step
method” and the alternative method
i) In Annex A, modification of the flux diagram to be in compliance with IEC 60193
j) In Annex B:
– Correction of the equation to obtain Δ
ECO
– Deletion of the clause which describes the direct step-up procedures for radial flow
machines
k) In Annex C, deletion of the clause which describes the direct step-up procedures for axial
flow machines
l) In Annex D:
– notes become main text
– change of variable names in Subclause D.1 for clarifications
m) Addition of Annex E, about comparison of IEC standards dealing with models: 60193 and
n) In Annex F, clarifications of equations by adding more subscripts
o) The Excel sheets attached to the standard are revised as itemized below
– Deletion of the routine regarding the direct step-up procedures for a whole turbine
– Deletion of the notice which requires mutual agreement when the step-up is applied to
high efficiency machines exceeding η
hAmax
– Addition of the routine to process the normalization of test data obtained at optimum
test conditions
p) Simplification of structure, calculation of optimum and individual point, step up calculation
with η
hAmax
IEC 62097:2019  IEC 2019 – 9 –
The text of this standard is based on the following documents:
FDIS Report of voting
4/359/FDIS 4/364/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 10 – IEC 62097:2019  IEC 2019
INTRODUCTION
0.1 General remarks
IEC 62097 forms an element of a series of standards which deals with model testing of
hydraulic machines. The series has two groups describing
a) Hydraulic turbines, storage pumps and pump-turbines – Model acceptance tests
(IEC 60193);
b) Hydraulic machines, radial and axial – Performance conversion method from model to
prototype (IEC 62097).
Advances in the technology of hydraulic machines for hydroelectric power plants provided
background for updating and revising the scale effect methodology of IEC 60193. The
advance in knowledge of scale effects originates from work done by research institutes,
manufacturers and relevant working groups within the organizations of IEC and IAHR. See
IEC 60193 and [1] to [6].
The method of calculating prototype efficiencies is supported by experimental work and
theoretical research on flow analysis and has been simplified for practical reasons and agreed
as a convention by [7] to [9]. The methodology is representing the present state of knowledge
of the transposition of performance from model to a homologous prototype.
Homology is not limited to the geometric similarity of the machine components; it also calls for
homologous velocity triangles at runner inlet and outlet [1].
According to the present state of knowledge, the formula for the efficiency transposition
calculation given in IEC 60193 and earlier standards often overestimates the transposition
increment of the efficiency for the prototype.
Limitations and applications of performance conversion of both standards (IEC 60193 and
IEC 62097) are given in Annex E.
This document is intended to be used mainly for the assessment of the results of contractual
model tests of hydraulic machines. If it is used for other purposes such as evaluation of
refurbishment of machines having very rough surfaces, special care is taken as described in
Annex B.
Due to the lack of sufficient knowledge about the loss distribution in Deriaz turbines, multi-
stage pump-turbines and storage pumps, this document does not provide the scale effect
formulae for them.
An Excel workbook concerning the conversion procedures of hydraulic machine performance
is attached as a complement of this document to facilitate the calculation of the scaled value
for a given test point.
When using this document, if any mismatch is found with IEC 60193, the information in
IEC 62097 prevails. Annex E provides additional information for performance conversion
method.
_____________
Numbers in square brackets refer to the bibliography.

IEC 62097:2019  IEC 2019 – 11 –
0.2 Basic features
A fundamental difference compared to the IEC 60193 transposition is the standardization of
scalable losses. In IEC 60193, a loss distribution factor V has been defined and standardized,
with the disadvantage that turbine designs which are not optimized will benefit from their
lower technological level.
This is certainly not correct, since a low efficiency design typically produces high non-scalable
losses, like incidence losses, whereby the amount of scalable losses is about constant for all
hydraulic machines, for a given type and a given specific speed of a hydraulic machine.
This document avoids all the inconsistencies connected with IEC 60193. A new basic feature
of this document is the separate consideration of losses in specific hydraulic energy, leakage
losses and disk friction losses [4], [7] to [9].
Above all, in this document, the transposition of the hydraulic performance is not only driven
by the dependence of friction losses on Reynolds number Re, but also the effect of surface
roughness Ra has been implemented.
Since the roughness of the actual machine component differs from part to part, scale effect is
evaluated for each individual part separately and then is finally summed up to obtain the
overall step-up for a complete machine [9]. For radial flow machines, the evaluation of scale
effect is conducted on five separate parts; spiral case, stay vanes, guide vanes, runner and
draft tube. For axial flow machines, the scalable losses in individual parts are not fully
clarified yet and are dealt with in two parts; runner blades and all the other stationary parts
inclusive.
The calculation procedures according to this document are summarized in Clause 8.
In case that the Excel workbook is used for evaluation of the results of a contractual model
test, each concerned party executes the calculation individually for cross-check using
common input data agreed on in advance for at least one test point.

– 12 – IEC 62097:2019  IEC 2019
HYDRAULIC MACHINES, RADIAL AND AXIAL – METHODOLOGY FOR
PERFORMANCE TRANSPOSITION FROM MODEL TO PROTOTYPE

1 Scope
This International Standard e
...