dc.creator | Milivojević, Sanja | |
dc.creator | Stevanović, Vladimir | |
dc.creator | Maslovarić, Blaženka | |
dc.date.accessioned | 2023-02-23T11:11:17Z | |
dc.date.available | 2023-02-23T11:11:17Z | |
dc.date.issued | 2013 | |
dc.identifier.uri | https://machinery.mas.bg.ac.rs/handle/123456789/4499 | |
dc.description.abstract | A direct contact of subcooled water and steam leads to condensation induced
water hammer (CIWH). Intensive condensation on water-steam interface causes
the water column movement towards the steam and acceleration of water mass
that replenishes the volume of condensed steam. Water column accelerates until it
splashes onto the closed end of the pipe, closed valve or onto another water
column leading to a high pressure increase in the pipeline or vessel system. The
impact pressure increase can cause mechanical damage of equipment and
endanger the safety of employees at the facility. According to available data of
plant accidents and carried out experiments, pressure increases over 10 MPa can
occur due to CIWH in a piping system that is initially at a low pressure close to
the atmospheric pressure. Prediction of possible occurrence of CIWH is necessary
to prevent accidents that this phenomenon can cause. A numerical model for the
simulation and analysis of the water hammer in the pipe two-phase flow is
developed. The modelling approach is based on one-dimensional compressible
flow, tracking of the interface between steam volume and water column and
modelling of the direct condensation of steam on subcooled liquid. Mass,
momentum and energy conservation equations are solved by the method of
characteristics. Fluid particle and the steam-water interface tracking are obtained
through a third-order accurate solving of the energy equation in space. The
thermodynamic quality, calculated from the enthalpy value, is used to determine
whether the observed computational region is filled with water, two-phase
mixture or steam. The condensation rate is strongly influenced by the negative or
positive acceleration of the water column. Under higher acceleration the steamwater
interface (water column head) bursts into huge amount of droplets. The area
of steam-water interface, i.e. the area for heat transfer exchange, suddenly
increases, which causes a higher condensation rate. The new model is introduced
that relates the interface area and the condensation heat transfer with the
acceleration of water column. Also, the transient friction is included in the
momentum equation due to intensive accelerations of the water column. The
model is applied to simulations and analyses of CIWH conditions in experimental
facilities. Numerical results are validated with available measured data. | sr |
dc.language.iso | en | sr |
dc.publisher | Nuclear Research Group of San Piero a Grado (GRNSPG) of the University of Pisa (UNIPI), the Nuclear and INdustrial Engineering (NINE) and the Thermalhydraulics Division of the American Nuclear Society (ANS) | sr |
dc.relation | info:eu-repo/grantAgreement/MESTD/Basic Research (BR or ON)/174014/RS// | sr |
dc.rights | restrictedAccess | sr |
dc.source | Proceedings of the 15th International Topical Meeting on Nuclear Reactor Thermal - Hydraulics (NURETH-15), Pisa, Italy, May 12-17, 2013 | sr |
dc.title | NUMERICAL SIMULATION OF CONDENSATION INDUCED WATER HAMMER | sr |
dc.type | conferenceObject | sr |
dc.rights.license | ARR | sr |
dc.citation.rank | M33 | |
dc.citation.spage | NURETH15-171 | |
dc.identifier.rcub | https://hdl.handle.net/21.15107/rcub_machinery_4499 | |
dc.type.version | publishedVersion | sr |