EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY CHARACTERISTICS
The paper presents the results of design, numerical, and experimental studies of models of pump-turbine flow passages for heads up to 200 m. The task was to improve the performance of the ORO170/5217 pump-turbine, which is successfully operated at 1-4 power units of the Dniester PSP. Using the softw...
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| Дата: | 2025 |
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| Автори: | , , , , , , |
| Формат: | Стаття |
| Мова: | Англійська |
| Опубліковано: |
Institute of Renewable Energy National Academy of Sciences of Ukraine
2025
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Репозитарії
Vidnovluvana energetika| _version_ | 1871103988931231744 |
|---|---|
| author | Khoryev , O. Rusanov , A. Lynnyk, O. Korotaiev, P. Bykov , Yu. Ahibalov , Ye. Maksymenko-Sheiko , K. |
| author_facet | Khoryev , O. Rusanov , A. Lynnyk, O. Korotaiev, P. Bykov , Yu. Ahibalov , Ye. Maksymenko-Sheiko , K. |
| author_institution_txt_mv | [
{
"author": "O. Khoryev ",
"institution": "A. Pidhornyi Institute of Power Machines and Systems NAS of Ukraine, Kharkiv, Ukraine"
},
{
"author": "A. Rusanov ",
"institution": "A. Pidhornyi Institute of Power Machines and Systems NAS of Ukraine, Kharkiv, Ukraine"
},
{
"author": " O. Lynnyk",
"institution": "JSC \"UKRENERGYMACHINES\", Kharkiv, Ukraine"
},
{
"author": " P. Korotaiev",
"institution": "A. Pidhornyi Institute of Power Machines and Systems NAS of Ukraine, Kharkiv, Ukraine"
},
{
"author": "Yu. Bykov ",
"institution": "A. Pidhornyi Institute of Power Machines and Systems NAS of Ukraine, Kharkiv, Ukraine"
},
{
"author": "Ye. Ahibalov ",
"institution": "A. Pidhornyi Institute of Power Machines and Systems NAS of Ukraine, Kharkiv, Ukraine"
},
{
"author": "K. Maksymenko-Sheiko ",
"institution": "A. Pidhornyi Institute of Power Machines and Systems NAS of Ukraine, Kharkiv, Ukraine"
}
] |
| author_sort | Khoryev , O. |
| baseUrl_str | https://ve.org.ua/index.php/journal/oai |
| collection | OJS |
| datestamp_date | 2026-07-18T06:32:22Z |
| description | The paper presents the results of design, numerical, and experimental studies of models of pump-turbine flow passages for heads up to 200 m. The task was to improve the performance of the ORO170/5217 pump-turbine, which is successfully operated at 1-4 power units of the Dniester PSP. Using the software developed at IPMach, a series of runners was designed to determine the effect of the number of blades on the power characteristics in turbine and pump modes. Using the proprietary IPMFlow software package developed at IPMach, preliminary numerical studies of the flow process in the turbine mode were carried out. Numerical modeling of the incompressible viscous fluid flow was performed by numerical integration of the Reynolds-averaged Navier-Stokes equations using artificial compressibility. The equations of fluid motion were supplemented by the differential two-parameter Menter SST model. The equations were integrated using the implicit quasi-monotonic Godunov scheme with second order approximation in space and time. The flow structure and energy performance of the new runners were compared with those of R5217. Selective experimental studies of pump-turbine models were carried out on the ECS-30 hydrodynamic test rig at IPMach. The test rig has no analogues in Ukraine, it is equipped with state-of-the-art devices and a set of measuring instruments, the performance of which meets the requirements of the international energy standard IEC 60193. In order to significantly reduce the research cost and time, the runner blades were manufactured using 3D printing technology from PLA plastic. The energy characteristics in turbine and pump modes were obtained. It was determined that in the turbine mode, the model with 7 blades is the most efficient in almost the entire range of operation at the plant – at the nominal head, its maximum efficiency is more than 2.5% higher than that of the original version. The geometric data of this runner was transferred to JSC “UKRENERGYMACHINES” for implementation in the project for the development of 5-7 hydraulic units of the Dniester PSP.  |
| doi_str_mv | 10.36296/1819-8058.2025.3(82).164-172 |
| first_indexed | 2025-10-01T01:30:54Z |
| format | Article |
| fulltext |
164
Відновлювана енергетика. № 3/2025 | Гідро-воднева енергетика
УДК 621.224 https://doi.org/10.36296/1819-8058.2025.3(82).164-172
EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY
CHARACTERISTICS
Received Apr. 28, 2025; accepted Sept. 22, 2025
Available online Sept. 30, 2025
Khoryev O.1, Rusanov A.2, Lynnyk O.3, Korotaiev P.4,
Bykov Yu.5, Ahibalov Ye.6, Maksymenko-Sheiko K.7
Author for correspondence: Bykov Yurii,
e-mail: yubykoff@gmail.com
The paper presents the results of design, numerical, and exper-
imental studies of models of pump-turbine flow passages for
heads up to 200 m. The task was to improve the performance
of the ORO170/5217 pump-turbine, which is successfully oper-
ated at 1-4 power units of the Dniester PSP. Using the software
developed at IPMach, a series of runners was designed to de-
termine the effect of the number of blades on the power char-
acteristics in turbine and pump modes. Using the proprietary
IPMFlow software package developed at IPMach, preliminary
numerical studies of the flow process in the turbine mode were
carried out. Numerical modeling of the incompressible viscous
fluid flow was performed by numerical integration of the Reyn-
olds-averaged Navier-Stokes equations using artificial com-
pressibility. The equations of fluid motion were supplemented by the differential two-parameter Menter SST
model. The equations were integrated using the implicit quasi-monotonic Godunov scheme with second order
approximation in space and time. The flow structure and energy performance of the new runners were compared
with those of R5217. Selective experimental studies of pump-turbine models were carried out on the ECS-30 hy-
drodynamic test rig at IPMach. The test rig has no analogues in Ukraine, it is equipped with state-of-the-art devices
and a set of measuring instruments, the performance of which meets the requirements of the international energy
standard IEC 60193. In order to significantly reduce the research cost and time, the runner blades were manufac-
tured using 3D printing technology from PLA plastic. The energy characteristics in turbine and pump modes were
obtained. It was determined that in the turbine mode, the model with 7 blades is the most efficient in almost the
entire range of operation at the plant – at the nominal head, its maximum efficiency is more than 2.5% higher
than that of the original version. The geometric data of this runner was transferred to JSC “UKRENER-
GYMACHINES” for implementation in the project for the development of 5-7 hydraulic units of the Dniester PSP.
Keywords: pump-turbine, runner, 3D blade (x-blade), numerical studies, hydrodynamic stand, experimental studies.
ВПЛИВ ГЕОМЕТРИЧНИХ ПАРАМЕТРІВ РОБОЧИХ КОЛІС НАСОС-ТУРБІНИ
НА ЕНЕРГЕТИЧНІ ХАРАКТЕРИСТИКИ
Отримано 28 квіт. 2025 р.; рекомендовано до публікації 22 вер. 2025 р.
Доступно онлайн 30 вер. 2025 р.
Хорєв О. М.1, Русанов А. В.2, Линник О. В.3,
Коротаєв П. О.4, Биков Ю. А.5, Агібалов Є. С.6,
Максименко-Шейко К. В.7
Автор для кореспонденції: Юрій Биков,
e-mail: yubykoff@gmail.com
Наведено результати проєктування, чисельних і експе-
риментальних досліджень моделей проточних частин
насос-турбіни на напори до 200 м. Ставилася задача
1 Cand. of Tech. Science (PhD)
https://orcid.org/0000-0001-6940-4183
2 Dr. of Eng. Sciences, Professor, Academician of
NAS of Ukraine
https://orcid.org/0000-0002-9957-8974
3 Design Engineer
https://orcid.org/0000-0003-1946-3032
4 Cand. of Tech. Science (PhD)
https://orcid.org/0000-0002-7473-9508
5 Cand. of Tech. Science (PhD)
https://orcid.org/0000-0001-7089-8993
6 Chief Engineer
https://orcid.org/0000-0003-3866-9992
7 Dr. of Eng. Sciences, Professor,
https://orcid.org/0000-0002-7064-2442
1, 2, 4, 5, 6, 7 A. Pidhornyi Institute of Power
Machines and Systems NAS of Ukraine, Kharkiv,
Ukraine
3 JSC "UKRENERGYMACHINES", Kharkiv, Ukraine
1 канд. техн. наук, ст. наук.співроб.,
https://orcid.org/0000-0001-6940-4183
2 д-р. техн. наук, професор, академік НАН
України
https://orcid.org/0000-0002-9957-8974
3 інженер-конструктор
https://orcid.org/0000-0001-7089-8993
4 канд. техн. наук
https://orcid.org/0000-0002-7473-9508
165
Відновлювана енергетика. № 3/2025 | Гідро-воднева енергетика
покращити показники насос-турбіни ОРО170/5217, яка
успішно експлуатується на 1–4 гідроагрегатах Дніс-
тровської ГАЕС. За допомогою розроблених в ІЕМС про-
грам спроєктовано серію робочих коліс з метою вияв-
лення впливу кількості лопатей на енергетичні
характеристики в турбінному та насосному режимах. З
використанням програмного комплексу IPMFlow, розро-
бленого в ІЕМС, проведено попередні чисельні дослі-
дження робочого процесу в турбінному режимі. Чисе-
льне моделювання течії нестисливої в’язкої рідини
виконано методом чисельного інтегрування рівнянь
Нав’є – Стокса, осереднених за Рейнольдсом, з викорис-
танням штучної стисливості. Рівняння руху рідини було доповнено диференціальною двопараметрич-
ною моделлю Ментера SST. Інтегрування рівнянь виконано за допомогою неявної квазімонотонної
схеми Годунова, що має другий порядок апроксимації за простором і часом. Виконано порівняння струк-
тури потоку й енергетичних показників нових коліс з РК5217. Селективні експериментальні дослі-
дження моделей насос-турбін проведено на гідродинамічному стенді ЕКС-30, ІЕМС. Стенд не має анало-
гів в Україні, він оснащений сучасним обладнанням і комплексом вимірювальної апаратури, показники
якої відповідають вимогам міжнародного енергетичного стандарту IEС 60193. З метою суттєвого
зниження вартості й скорочення термінів досліджень лопаті робочих коліс були виготовлені за техно-
логією 3D-друку з пластику PLA. Отримано енергетичні характеристики в турбінному та насосному
режимах. Визначено, що в турбінному режимі практично в усьому діапазоні роботи на станції найефе-
ктивнішою є модель з 7 лопатями – за номінального напору його максимальний ККД більш ніж на 2,5 %
перевищує ефективність вихідного варіанта. Геометричні дані цього колеса передано в АТ «Українські
енергетичні машини» для впровадження в проєкті розроблення 5–7 гідроагрегатів Дністровської ГАЕС.
Ключові слова: насос-турбіна, робоче колесо, просторова лопать (x-blade), чисельні дослідження, гідро-
динамічний стенд, експериментальні дослідження.
Introduction
As of early 2025, renewable energy sources accounted for
46% of the world's installed capacity. Their growth in 2024
reached 15.1%, primarily due to the outstripping expansion
of solar and wind power plants [1]. Under such conditions,
the role of hydraulic power plants (HPPs) and pumped stor-
age plants (PSPs) is significantly increasing, since their units
are capable of flexibly equalizing the peak portion of the
daily load curve and serve as an emergency and frequency
reserve for power systems. Therefore, the development of
the theory and practice of researching hydraulic machines
for HPPs and PSPs is growing. Today, when designing the
flow passages of turbines and pump-turbines, require-
ments are imposed not only to improve their performance
and ensure the necessary cavitation characteristics, but
also to expand the range of operation in turbine mode to
cover the partial load range [2, 3]. One of the main factors
limiting the operating range at partial loads is the formation
of a vortex rope in the draft tube downstream of the run-
ner, the precession of which may induce vibrations of the
entire hydraulic unit [4].
The study of the flow process in hydraulic machine models
is carried out both using numerical methods and on exper-
imental hydrodynamic test rigs [5, 6, 7, 8]. Numerical stud-
ies provide detailed information on the flow structure in all
elements of the flow passage, provide information on pos-
sible reserves for increasing efficiency, and significantly re-
duce the time and cost of design. Experimental tests on
hydrodynamic test rigs allow us to determine energy and
cavitation properties in a wide range of operating condi-
tions with better accuracy.
Solving the problems of increasing turbine efficiency and ex-
panding the range of their operation in turbine mode is a
highly complex problem. There is no single method to solve
it. There are several main directions for finding a solution to
this problem. One of the most promising for radial-axis hy-
draulic machines is the method of spatial profiling of runner
blades, including the so-called X-blades. GE Energy's X-blade
design for Francis hydroturbines was first developed in the
early stages of the Chinese Three Gorges project [9], pa-
tented and implemented in other projects around the world.
An effective method of improving the performance and ex-
panding the range of operation of radial-axis hydraulic ma-
chines is the use of runners with additional shortened
blades – splitters. Paper [10] considers the effect of using
splitter blades on the intensity of the vortex rope, paper
[11] – on cavitation parameters, paper [12] – on energy and
pulsation parameters, and paper [13] considers optimiza-
tion methods for designing runners with splitters. Numeri-
cal and experimental studies into the effect of the length of
splitter blades on the energy performance of a pump-tur-
bine for heads up to 200 m in turbine and pump modes
were carried out at IPMach [14, 15].
In order to reduce the intensity of vortex rope at low flow
rates and, accordingly, to expand the operating range of
5 канд. техн. наук
https://orcid.org/0000-0001-7089-8993
6 головний інженер
https://orcid.org/0000-0003-3866-9992
7 д-р. техн. наук, професор
https://orcid.org/0000-0002-7064-2442
1, 2, 4, 5, 6, 7 Інститут енергетичних машин
і систем ім. А. М. Підгорного НАН України,
Харків, Україна
3 АТ «Українські енергетичні машини»,
Харків, Україна
166
Відновлювана енергетика. № 3/2025 | Гідро-воднева енергетика
high-pressure radial-axis hydraulic machines, air or water is
injected behind the runner [16, 17, 18]. This leads to a re-
duction in the level of pulsations, but at the same time, the
efficiency and power of the turbine are reduced. Paper [16]
examines the effect of the amount of water and air at the
inlet on the level of pressure pulsations. The results showed
that the most optimal volumetric flow rates of air and wa-
ter are 1.63 % and 0.65 %, respectively, with an air nozzle
diameter of 0.019 m, which reduces pressure fluctuations
by 33.44 %. Paper [17] presents the results of pressurized
air injection in the Kaplan turbine model to mitigate flow
cavitation after the fairing. Paper [18] considers the flow
characteristics of a Francis turbine under conditions of air
injection at low flow rates/power.
In order to improve the efficiency of a pump-turbine for
heads up to 200 m, the authors investigated the effect of
the number of significantly spatial blades (x-shaped blades)
and the shape of the suction edge of the runner on the en-
ergy characteristics.
Problem statement
As the initial variant, the ORO170/5217 pump-turbine (de-
veloped by IPMach) was chosen, which is successfully oper-
ated at 1-4 power units of the Dniester PSP.
The flow passage of the pump-turbine model (Fig. 1) in-
cludes a spiral case (1) with a stator (2), guide vanes (3), a
runner (4), and a draft tube (5).
The spiral case is designed according to the law Vu = const,
the coverage angle in the plan view is φ = 360°, and has cir-
cular cross-sections. The stator with the possibility of in-
stalling an annular gate has 20 profiled stay vanes, including
a tongue vane. The guide vanes have 20 blades with an
asymmetric positive curvature profile with a height of b0 =
0.14D1, the rotation axis is located at a diameter of D0 =
1.2D1. The runner with a diameter of D1 = 350 mm has 7
blades. The draft tube consists of a vertical diffuser (Fig. 1
– 5a) with a taper of about 5° per side; a unified KU-3RO
elbow (5b); and a constant diameter outlet tube (5c). Total
height of the draft tube h = 3.19D1, length L = 4.5D1.
Fig. 1. Flow passage of the pump-turbine model
Paper [8] experimentally established the dependencies of
the influence of spatial profiling of radial-axial runner
blades using circumferential lean on energy characteristics.
Based on the analysis of those results, work was carried out
to study the influence of the geometric parameters of the
runners (primarily the number of blades z and the shape of
the suction edge) of the pump-turbine on the efficiency of
models in turbine and pump modes. To increase the surface
area of the blade relative to the original version and im-
prove the conditions of its flow in the peripheral zone, the
suction edge was moved downstream (Fig. 2). All other el-
ements of the flow passage were left unchanged.
Fig. 2. Meridional projection of flow passages R5217 and R5252
0
20
40
60
80
100
120
140
020406080100120140160180200
R5217
R5252
167
Відновлювана енергетика. № 3/2025 | Гідро-воднева енергетика
According to the methods and programs developed at IEMS
[19, 20, 21], a series of 4 new runners, called 5252, with a
different number of blades – from 6 to 9 – was designed
and numerically studied. They were named R5252M6,
R5252M7, R5252M8, and R5252M9 according to the num-
ber of blades. The blades were profiled by solving the dif-
ferential equation of the streamline in the plan view. For
each runner, the most efficient ratios of the bladewrap an-
gles to inlet and outlet angles were determined. Table 1
shows the geometric parameters of the runners of the 5252
series and the original version.
Table 1. Geometric parameters of runners of the 5252 se-
ries and the original R5217
Model
name
z
β1per,
°
β2per,
°
φper, °
φhub -
φper, °
Lean
γ, °
Lper, m
R5217 7 – – 96.3 2.83 +10 0.25123
R5252M6 6 28.3 15.6 104.2 15.64 -30 0.26003
R5252M7 7 28.1 15.6 96.2 15.64 -30 0.26003
R5252M8 8 28.0 15.5 90.7 15.64 -30 0.26003
R5252M9 9 28.0 14.6 85.1 15.64 -30 0.26003
The table denotes: z is the number of blades; β1per is the
geometric angle at the inlet of the peripheral profile;
β2per is the geometric angle at the outlet of the periph-
eral profile; φper is the peripheral profile's coverage an-
gle; φhub - φper is the difference between the coverage
angles of the hub and peripheral profiles; γ is the lean
angle of the pressure (inlet) edge; Lper is the length of the
meridional projection of the peripheral profile (for run-
ner diameter of 1 m).
Results of numerical studies
The study of the energy characteristics of the 5252 series of
runners by simplified methods – the program of profile flow
on axisymmetric streamline surfaces in a layer of variable
thickness – showed that the best performance is provided
by the R5252M7 runner with 7 blades. In addition, this
number of blades is specified in the Terms of Reference for
the development of a pump-turbine model for 5-7 hydrau-
lic units of the Dniester PSP. Therefore, numerical studies
of the spatial flow in the flow passage were carried out for
the R5252M7 model. The results were compared with the
data from the original R5217 model.
The viscous incompressible fluid flow in the flow passages
was modeled using the IPMFlow software package (devel-
oped by IPMach) based on the numerical solution of the
Reynold’s-averaged Navier-Stokes equations with artificial
compressibility.
The flow turbulence was modeled using Menter’s two-pa-
rameter SST model. The numerical integration of the equa-
tions was performed using the implicit quasi-monotonic
Godunov’s second-order scheme.
The study was carried out in the turbine mode within com-
putational domains containing one channel of the guide
vane and runner. The computational mesh was a normal-
ized hexagonal mesh with 72·72·80 = 414,720 and
80·80·100 = 640,000 elements in the channel of the guide
vane and runner, respectively, with densification near the
walls, and the value of the y+ indicator did not exceed 10.
Fig. 3 shows pressure distribution diagrams along the mid-
span-sections of the blades of two runners in the turbine
mode at a rotation speed corresponding to the design head
at the plant when the guide vanes are opened a0 = 24 mm,
which is close to the optimum.
Fig. 3. Pressure diagrams at the mid-span sections of the blades for three variants of runners, at the design head (nI’ = 91
min-1) with the guide vane opening of a0 = 24 mm, in turbine mode
It is obvious that R5252M7 has a more uniform pressure
distribution, especially on the pressure side. In R5252M7,
in the area of the trailing edge on the suction side, there is
a zone (approximately 22 % of the profile length) where the
pressure value practically does not change, and the suction
at the outlet is less than in the original R5217, which should
lead to improved cavitation characteristics.
Fig. 4 shows the distribution of the axial, radial, and circum-
ferential components of the absolute velocity at the outlet
of the runner in front of the draft tube cone for two variants
of runners under the same mode.
The new R5252M7 exhibits a more uniform distribution of
velocity components downstream of the runner, especially
for the axial and circumferential components. This indi-
cates better head utilization by the new runner, the for-
mation of more favorable conditions at the draft tube inlet,
thereby providing a sound basis to expect an increase in the
efficiency of this runner.
168
Відновлювана енергетика. № 3/2025 | Гідро-воднева енергетика
Fig. 4. Distribution of the axial Vz, radial Vr and circumferential Vu components of the velocity at the runner outlet at the
design head (nI’ = 91 min-1) with the guide vane opening of a0 = 24 mm
Comparison of the calculated efficiency values for models
with two runner variants showed that the model with the
new R5252M7 has better performance in almost the entire
operating range of the Dniester PSP. Fig. 5 shows, as an
example, the dependence of the efficiency of the calcula-
tion domains containing the channels of the guide vane and
runner on the flow rate at the maximum and design heads
at the plant.
Fig. 5. Dependences of the calculated efficiency on the opening of the guide vanes in pump-turbine models with three
variants of runners in the turbine mode: a) maximum head (nI’ = 85 min-1); b) nominal head (nI’ = 91 min-1)
Results of experimental studies
Selective experimental studies of working processes in
pump-turbines were carried out on the hydrodynamic test
rig ECS-30 of the IPMach Hydraulic Machines Laboratory.
The rig has no analogues in Ukraine; in 2007, it was granted
the status of a national heritage. The test rig is equipped
with modern equipment and a set of measuring instru-
ments, the performance of which meets the requirements
of the international energy standard IEC 60193, primarily in
terms of the efficiency error of ±0.25%. The main parame-
ters of the experimental equipment are: diameter of
runner models up to 500 mm; head up to 30 m; flow
rate/supply up to 0.300/0.500 m3/s; motor generator
power 200 kW. A simplified diagram is shown in Fig. 6. The
numbers denote: 1 – model unit; 2 – balancing machine; 3
– head water tank; 4 – tailwater tank; 5 – electromagnetic
flow meter (main) and Venturi flow meter (backup); 6 –
head pipeline; 7 – circulation pump; 8 – absorber; 9 – drain-
age pipeline. A more detailed description of the test stand
can be found in [7, 14]. The Reynolds numbers in the stud-
ies were in the range Re = 2.0·106...3.0·106 and were rec-
orded in the protocols for each operating point.
Fig. 6. Simplified diagram of the hydrodynamic test stand ECS-30
169
Відновлювана енергетика. № 3/2025 | Гідро-воднева енергетика
In order to reduce the cost of manufacturing the model
block and shorten the test period, the runner blades were
made using 3D printing technology from PLA plastic (Fig. 7).
The blades were printed in a layerwise fashion with a layer
thickness of 0.1 mm, which ensured high quality of the
blade surfaces. The hub is made of stainless steel, and the
lower covering disk is made of transparent block plexiglass.
It is attached to the blades with screws and dichloroethane-
based glue. The design of the runners is lightweight and
quite durable. A preliminary strength calculation showed
that the model can be tested on a rig at pressures of up to
15 m, which ensures reliable results.
Fig. 7. Runner models of the 5252 series
Experimental studies of four variants of runners in the tur-
bine mode were carried out at a head of 6 m, in the pump
mode at a rotor speed of 700 min-1. The opening of the
guide vanes varied from 12 to 34 mm in the range of varia-
tion of the unit flow rate/supply QI’ from 0.100 to 0.600
m3/s. The operating characteristics were obtained, and a
hill chart was built on their basis. Table 2 shows the param-
eters of the optimal modes of the 5252 series models with
four variants of runners and the original version with
R5217. The relative efficiency η* hereinafter refers to the
ratio of its current value to the maximum efficiency of the
model with the original R5217.
Table 2. Parameters of optimal turbine and pump modes of models with different runners
Runner
Optimal turbine mode Optimal pump mode
QI
',
m3/s
nI
',
min-1
η*,
%
QI
',
m3/s
nI
',
min-1
η*,
%
1 R5217 0.312 78.0 100.00 0.402 92.1 100.00
2 R5252M6 0.350 79.6 99.54 0.358 91.0 98.63
3 R5252M7 0.329 77.5 101.26 0.383 90.7 99.91
4 R5252M8 0.353 78.3 101.11 0.395 91.6 99.66
5 R5252M9 0.352 79.5 100.54 0.425 92.2 99.02
Table 2 shows that all models of the 5252 series, except for
the R5252M6 with six blades, have higher values of maxi-
mum efficiency in turbine mode than the original model
with R5217. The best performance is achieved by the model
with R5252M7, which is more than 1.1% higher in absolute
terms than the original. Models with runners of the new se-
ries have slightly higher flow rates at the optimum, while
the rotation speeds differ to a lesser extent. In pump mode,
the maximum efficiency was obtained in the model with
the original R5217. It should also be noted that the maxi-
mum efficiency of the models with R5252M7 and R5252M8
is high – their absolute values are 0.08 and 0.30% lower
than the original runner, respectively. With the increase in
the number of blades in models with runners of the 5252
series, the value of the optimal unit flow rate increases in
the pump mode.
Fig. 8 shows the dependence of the efficiency on the flow
rate of models with runners of the 5217 and 5252 series in
turbine mode at different values of the unit speed corre-
sponding to the design frequency for the flow passage (nI’
= 80 min-1), as well as the maximum, nominal, and mini-
mum heads at the Dniester PSP.
170
Відновлювана енергетика. № 3/2025 | Гідро-воднева енергетика
a b
c d
Fig. 8. Dependences of efficiency on flow rate of runner models of 5217 and 5252 series in turbine mode at different val-
ues of nI’: a) design rotation speed nI’ = 80 min-1; b) maximum head nI’ = 85 min-1;
c) nominal head nI’ = 91 min-1; d) minimum head nI’ = 95 min-1
The results show that the choice of rational geometric pa-
rameters of the runner blades made it possible to signifi-
cantly improve the performance of the pump-turbine mod-
els. In almost the entire range of flow rates at all heads at
the plant, the most efficient model is the R5252M7 with 7
blades. For example, at the design head (nI’ = 91 min-1), its
maximum efficiency is more than 2.5% higher than that of
the original version; at the maximum head (nI’ = 85 min-1),
it is 1.5% higher, and at the minimum head (nI’ = 95 min-1),
it is more than 3.5% higher. Other models of the 5252 series
also have better performance than the original. This result
was achieved primarily by optimizing the layout of the de-
sign profiles during the spatial profiling of the runner
blades, as well as by changing the position of the suction
edge in the meridional projection, which increases the
blade area.
Fig. 9 shows the dependence of the efficiency and head on
the flow rate of models with runners of the 5217 and 5252
series in the pump mode at the opening of the guide vanes
a0 = 26 mm, which is practically optimal for all the studied
models.
The number of blades primarily determines the pressure
head of the pump-turbine models, so the highest pressure
head is expected for the R5252M9 model with 9 blades, and
the lowest – for the R5252M6 model with 6 blades. The
head curves within the acceptable operation region – ex-
tending to the surge zone at low flow rates – are almost
parallel. The best energy curves were obtained for the orig-
inal R5217 and for the new R5252M7 and R5252M8 models
– their characteristics exhibit rather wide flow ranges with
a high level of efficiency. The lowest efficiency was ob-
tained in the model with R5252M6 with six blades.
Conclusions
As a result of experimental studies on the hydrodynamic
test rig investigating the effect of the geometric parameters
of the pump-turbine runners on heads up to 200 m, it was
found that the seven-blade model R5252M7 exhibits the
best energy characteristics. In the turbine mode, it
171
Відновлювана енергетика. № 3/2025 | Гідро-воднева енергетика
outperforms the original model R5217, which is installed
and successfully operated at units 1-4 of the Dniester PSP,
across almost the entire operating range of the plant. For
example, at the design head, its maximum efficiency is
more than 2.5% higher than that of the original version.
Other models of the 5252 series in turbine mode also
demonstrate better performance than the R5217 due to
the application of spatial runner blade profiling s and ra-
tional selection of blade edges. In the pump mode, the
R5217 and R5252M7 models show nearly identical head to
the surge zone at low flow rates, and the difference in their
maximum efficiency values does not exceed 0.08% in abso-
lute terms. Therefore, the R5252M7 model was handed
over to the JSC "UKRENERGYMACHINES" to manufacture a
metallic model with a runner diameter of 500 mm, in-
tended for a complete program of model testing and po-
tential implementation at power units 5-7 of the Dniester
PSP.
Fig. 9. Dependences of efficiency and head on the flow rate of runner models of 5217 and 5252 series in pump mode at
the opening of the guide vanes a0 = 26 mm
Gratitude
The research was carried out within the framework of the
state project of the National Academy of Sciences of
Ukraine No. III-25-24 “Improving the efficiency of working
processes and the reliability of elements of power ma-
chines and technological equipment using methods of
mathematical and physical modeling” and the contract
with JSC "UKRENERGYMACHINES" “Development, mathe-
matical and experimental research of pump-turbine flow
passage models on the parameters of the Dniester PSP.
Conducting acceptance model tests” No. V-23-2022.
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|
| id | veorgua-article-560 |
| institution | Vidnovluvana energetika |
| keywords_txt_mv | keywords |
| language | English |
| last_indexed | 2026-07-19T01:16:57Z |
| publishDate | 2025 |
| publisher | Institute of Renewable Energy National Academy of Sciences of Ukraine |
| record_format | ojs |
| resource_txt_mv | veorgua/44/db9b752b2db962ce35f89f7898755044.pdf |
| spelling | veorgua-article-5602026-07-18T06:32:22Z EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY CHARACTERISTICS ВПЛИВ ГЕОМЕТРИЧНИХ ПАРАМЕТРІВ РОБОЧИХ КОЛІС НАСОС-ТУРБІНИ НА ЕНЕРГЕТИЧНІ ХАРАКТЕРИСТИКИ Khoryev , O. Rusanov , A. Lynnyk, O. Korotaiev, P. Bykov , Yu. Ahibalov , Ye. Maksymenko-Sheiko , K. pump-turbine, runner, 3D blade (x-blade), numerical studies, hydrodynamic stand, experimental studies. насос-турбіна, робоче колесо, просторова лопать (x-blade), чисельні дослідження, гідродинамічний стенд, експериментальні дослідження. The paper presents the results of design, numerical, and experimental studies of models of pump-turbine flow passages for heads up to 200 m. The task was to improve the performance of the ORO170/5217 pump-turbine, which is successfully operated at 1-4 power units of the Dniester PSP. Using the software developed at IPMach, a series of runners was designed to determine the effect of the number of blades on the power characteristics in turbine and pump modes. Using the proprietary IPMFlow software package developed at IPMach, preliminary numerical studies of the flow process in the turbine mode were carried out. Numerical modeling of the incompressible viscous fluid flow was performed by numerical integration of the Reynolds-averaged Navier-Stokes equations using artificial compressibility. The equations of fluid motion were supplemented by the differential two-parameter Menter SST model. The equations were integrated using the implicit quasi-monotonic Godunov scheme with second order approximation in space and time. The flow structure and energy performance of the new runners were compared with those of R5217. Selective experimental studies of pump-turbine models were carried out on the ECS-30 hydrodynamic test rig at IPMach. The test rig has no analogues in Ukraine, it is equipped with state-of-the-art devices and a set of measuring instruments, the performance of which meets the requirements of the international energy standard IEC 60193. In order to significantly reduce the research cost and time, the runner blades were manufactured using 3D printing technology from PLA plastic. The energy characteristics in turbine and pump modes were obtained. It was determined that in the turbine mode, the model with 7 blades is the most efficient in almost the entire range of operation at the plant – at the nominal head, its maximum efficiency is more than 2.5% higher than that of the original version. The geometric data of this runner was transferred to JSC “UKRENERGYMACHINES” for implementation in the project for the development of 5-7 hydraulic units of the Dniester PSP.  Наведено результати проєктування, чисельних і експериментальних досліджень моделей проточних частин насос-турбіни на напори до 200 м. Ставилася задача покращити показники насос-турбіни ОРО170/5217, яка успішно експлуатується на 1–4 гідроагрегатах Дністровської ГАЕС. За допомогою розроблених в ІЕМС програм спроєктовано серію робочих коліс з метою виявлення впливу кількості лопатей на енергетичні характеристики в турбінному та насосному режимах. З використанням програмного комплексу IPMFlow, розробленого в ІЕМС, проведено попередні чисельні дослідження робочого процесу в турбінному режимі. Чисельне моделювання течії нестисливої в’язкої рідини виконано методом чисельного інтегрування рівнянь Нав’є – Стокса, осереднених за Рейнольдсом, з використанням штучної стисливості. Рівняння руху рідини було доповнено диференціальною двопараметричною моделлю Ментера SST. Інтегрування рівнянь виконано за допомогою неявної квазімонотонної схеми Годунова, що має другий порядок апроксимації за простором і часом. Виконано порівняння структури потоку й енергетичних показників нових коліс з РК5217. Селективні експериментальні дослідження моделей насос-турбін проведено на гідродинамічному стенді ЕКС-30, ІЕМС. Стенд не має аналогів в Україні, він оснащений сучасним обладнанням і комплексом вимірювальної апаратури, показники якої відповідають вимогам міжнародного енергетичного стандарту IEС 60193. З метою суттєвого зниження вартості й скорочення термінів досліджень лопаті робочих коліс були виготовлені за технологією 3D-друку з пластику PLA. Отримано енергетичні характеристики в турбінному та насосному режимах. Визначено, що в турбінному режимі практично в усьому діапазоні роботи на станції найефективнішою є модель з 7 лопатями – за номінального напору його максимальний ККД більш ніж на 2,5 % перевищує ефективність вихідного варіанта. Геометричні дані цього Дністровської ГАЕС. колеса передано в АТ «Українські енергетичні машини» для впровадження в проєкті розроблення 5–7 гідроагрегатів Institute of Renewable Energy National Academy of Sciences of Ukraine 2025-09-28 Article Article application/pdf https://ve.org.ua/index.php/journal/article/view/560 10.36296/1819-8058.2025.3(82).164-172 Vidnovluvana energetika ; No. 3(82) (2025): Scientific and applied Journal renewable energy ; 164-172 Возобновляемая энергетика; ##issue.no## 3(82) (2025): Scientific and applied Journal renewable energy ; 164-172 Відновлювана енергетика; № 3(82) (2025): Науково-прикладний журнал Відновлювана енергетика; 164-172 2664-8172 1819-8058 10.36296/1819-8058.2025.3(82) en https://ve.org.ua/index.php/journal/article/view/560/470 Copyright (c) 2025 O. Khoryev , A. Rusanov , O. Lynnyk, P. Korotaiev, Yu. Bykov , Ye. Ahibalov , K. Maksymenko-Sheiko https://creativecommons.org/licenses/by-nc-nd/4.0 |
| spellingShingle | pump-turbine runner 3D blade (x-blade) numerical studies hydrodynamic stand experimental studies. Khoryev , O. Rusanov , A. Lynnyk, O. Korotaiev, P. Bykov , Yu. Ahibalov , Ye. Maksymenko-Sheiko , K. EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY CHARACTERISTICS |
| title | EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY CHARACTERISTICS |
| title_alt | ВПЛИВ ГЕОМЕТРИЧНИХ ПАРАМЕТРІВ РОБОЧИХ КОЛІС НАСОС-ТУРБІНИ НА ЕНЕРГЕТИЧНІ ХАРАКТЕРИСТИКИ |
| title_full | EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY CHARACTERISTICS |
| title_fullStr | EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY CHARACTERISTICS |
| title_full_unstemmed | EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY CHARACTERISTICS |
| title_short | EFFECT OF GEOMETRICAL PARAMETERS OF PUMP-TURBINE RUNNERS ON ENERGY CHARACTERISTICS |
| title_sort | effect of geometrical parameters of pump-turbine runners on energy characteristics |
| topic | pump-turbine runner 3D blade (x-blade) numerical studies hydrodynamic stand experimental studies. |
| topic_facet | pump-turbine runner 3D blade (x-blade) numerical studies hydrodynamic stand experimental studies. насос-турбіна робоче колесо просторова лопать (x-blade) чисельні дослідження гідродинамічний стенд експериментальні дослідження. |
| url | https://ve.org.ua/index.php/journal/article/view/560 |
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