Effect of pressure-balance pipes on the axial hydraulic thrust of a reversible pump-turbine under the runaway condition
Physics of Fluids,
Год журнала:
2025,
Номер
37(2)
Опубликована: Фев. 1, 2025
Axial
hydraulic
thrust
is
a
crucial
factor
contributing
to
the
unstable
operation
of
pump-turbine
especially
under
off-design
conditions.
Pressure-balance
pipe
can
effectively
achieve
axial
balance
pump-turbine.
In
this
study,
impact
diameter
and
location
pressure-balance
on
runaway
condition
investigated.
The
influence
mechanism
pressure
distribution
internal
flow
patterns
further
explored.
results
show
that
pipes
have
relatively
minor
while
increase
in
causes
rise
thrust.
Compared
with
outer
pipe,
inner
demonstrates
more
significant
effect
force
runner.
Additionally,
low-frequency
components
at
0.6
times
runner
rotational
frequency
are
observed,
which
indicate
occurrence
stall
vaneless
area.
variation
also
affects
number
passages
vortices,
as
well
quantity
vortices.
With
diameter,
backflow
phenomena
negative
regions
gradually
emerge
result
chaotic
flow.
Язык: Английский
Comprehensive assessment and analysis of cavitation scale effects on energy conversion and stability in pumped hydro energy storage units
Energy Conversion and Management,
Год журнала:
2024,
Номер
325, С. 119370 - 119370
Опубликована: Дек. 12, 2024
Язык: Английский
Numerical investigation of internal flow characteristics in an azimuth waterjet propulsion at different ship speeds
Applied Ocean Research,
Год журнала:
2025,
Номер
154, С. 104406 - 104406
Опубликована: Янв. 1, 2025
Язык: Английский
Development of firefighting systems for coastal facilities using water-jet powered fire boats
E3S Web of Conferences,
Год журнала:
2025,
Номер
627, С. 05023 - 05023
Опубликована: Янв. 1, 2025
The
article
is
devoted
to
the
analysis
of
fires
and
their
extinguishing
at
coastal
facilities
using
mobile
fire
departments
ensure
safety
people,
property
environment.
authors
considered
effective
specialized
methods
technologies,
including
use
boats
with
a
water
jet
engine.
parameters
operation
pump
hose
systems
were
calculated,
maximum
distance
from
site
rescue
boat
distribution
forces
means
protection
units
determined.
Язык: Английский
Evolution of large-scale flow structures in an axial-flow pump during performance breakdown
Physics of Fluids,
Год журнала:
2024,
Номер
36(9)
Опубликована: Сен. 1, 2024
This
paper
presents
a
very
large
eddy
simulation
analysis
of
the
unsteady
flow
in
pre-stall
to
stall
transition
process
an
axial-flow
pump,
with
aim
elucidate
spatiotemporal
evolution
large-scale
structures
during
performance
breakdown
pump.
The
transient
is
investigated
utilizing
time-dependent
rate
computation
scheme.
results
demonstrate
that,
as
dynamically
reduced,
reduction
pump
head
found
lags
behind
by
approximately
15
impeller
revolutions.
leading
edge
separation
on
blade
suction
side
(SS)
evolves
into
vortex
(LSV)
conjunction
dynamic
rate.
attached
SS
vicinity
hub
and
trailing
squeezes
mainstream
outwards,
resulting
formation
cross
passage
(CPV)
tip
passage.
combined
effect
LSV,
CPV,
tip-clearance
induces
penetrating
upstream
region
impeller,
which
gives
rise
swirling
backflow
within
inlet
pipe.
At
stall,
CPV
stably
extends
neighboring
blade.
Furthermore,
observed
near
junction
hub,
it
collides
inflow
hub-attached
vortex.
Язык: Английский