PAPERS SELECTED FOR THE SYMPOSIUM

• Turbulent Two-Phase Flow Modeling of Air-Coal Mixture Channels with Single Blade Turbulators

  Rastko Jovanović, Dejan Cvetinović, Predrag Stefanović, Zoran Marković, Zoran Pavlović - Institut za nuklearne nauke VINČA, Laboratorija za termotehniku i energetiku, Bartosz Swiatkowski - Thermal Processes Department, Institute of Power Engineering, Mory 8, 01-330 Warsaw, Poland

  Abstract Text

  Subject of this work is turbulent two-phase flow through air-coal channel(s) of complex geometry. Air flow through all eight air-coal mixture channels was simulated in first stage. Velocity and pressure field were obtained as results of this simulation. One channel... show full text »
  Abstract Text

  Subject of this work is turbulent two-phase flow through air-coal channel(s) of complex geometry. Air flow through all eight air-coal mixture channels was simulated in first stage. Velocity and pressure field were obtained as results of this simulation. One channel was selected, based on obtained results from first case. Two-phase flow was simulated in this channel. Lagrangian multiphase model was used for discrete phase (coal particles) modeling. Two-phase flow in air-coal mixture channel without turbulator was simulated next. After that, two-phase flow in air-coal mixture channels with two different turbulator heights was simulated. Turbulators were set parallel to velocity vectors at inlet. Finally turbulators were rotated for 12 deg. around x-axis in positive mathematical direction, and simulation was repeated for both turbulator heights. The aim of this work is numerical optimization of fluid flow and coal particle distribution in reconstructed air-coal mixture channels. Single blade turbulator was used to increase turbulence in vertical section of air-coal mixture channel. Standard k-ω turbulent model was used for modeling turbulence. Lagrangian multiphase model was used for modeling coal particle distribution. More uniform coal particle distribution has been achieved using single blade turbulators. Results show that there is no significant difference in coal particle distribution between all four cases in which different turbulator geometry and position was used. Upon these conclusions, technologically simplest solution, turbulator with low height, can be suggested. Although better particle distribution is reached using single blade turbulators, particle concentration in evaluation section (where plasma generators will be built in) still remained anisotropic. Because uniform coal particle distribution is of great importance for proper work of plasma generators, other solutions for achieving this goal will be object of future analysis. « hide
  Symposium Session: Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana

• DOPRINOS NACIONALNOG PROGRAMA ENERGETSKE EFIKASNOSTI EFIKASNOM RADU ELEKTROENERGETSKOG SISTEMA SRBIJE

  Simeon Oka, Emilija Turković, Predrag Stefanović, Maja Đurović-Petrović - Matični naučni odbor za energetsku efikasnost Ministarstva nauke i tehnološkog razvoja Republike Srbije

  Abstract Text

  Elektroenergetski sistem Srbije je jedan od najvećih, ako ne i najveći, i tehnološki najrazvijeniji tehnički sistem u Srbiji. U pogonu je 8 termoelektrana sa 25 blokova koje kao pogonsko gorivo koriste lignit (Nikola Tesla A 6, Nikola Tesla B 2,... show full text »
  Abstract Text

  Elektroenergetski sistem Srbije je jedan od najvećih, ako ne i najveći, i tehnološki najrazvijeniji tehnički sistem u Srbiji. U pogonu je 8 termoelektrana sa 25 blokova koje kao pogonsko gorivo koriste lignit (Nikola Tesla A 6, Nikola Tesla B 2, Kolubara 5 i Morava sa jednim blokom, zatim Kostolac A 2 i Kostolac B 2, i konačno Kosovo A 5 i B 2 bloka) i devet hidroelektrana sa pedeset hidro-agregata (Đerdap I 6, Đerdap II 10 agregata, Pirot 2, Vlasina 10, Bajina Bašta 4, RHE Bajina Bašta 2, Limske HE 8, Zvornik 4 i Elektromorava 4 agregata). Ukupna instalirana snaga elektroenergetskih izvora je 7120 MW (3936MW u TE na lignit, 2.831 MW u HE i 353 MW u TE-TO na mazut i prirodni gas), bez termoelektrana na teritoriji Kosova i Metohije (1235 MW), koje trenutno ne rade u sastavu elektroenergetskog sistema Srbije. Sistem za prenos električne energije čini oko 10.200 km dalekovoda 400, 220 i 110 kV i oko 27 GVA instaliranih u transformatorskim stanicama, preko koga se vrši prenos električne energije proizvedene u zemlji i obavlja razmena sa susednim sistemima. Sistem za distribuciju električne energije ima mrežu dužine preko 150.000 km sa 34,318 transformatorskih stanica. Iako je učešće instaliranog kapaciteta hidroelektrana skoro 40%, proizvodnja električne energije u termoelektranama je značajno veća. U 2007 godini u elektranama EPS-a je proizvedeno 38.897 GWh električne energije. Učešće termoelektrana u proizvodnji iznosilo je 73.20%. Na površinskim kopovima u kolubarskom i kostolačkom basenu povećana je proizvodnja na 36.506.746 tona lignita, od čega u površinskom kopu Kolubara oko 80%. Sa stanovišta proizvodnje električne energije u sistemu, proizvodnja mrkog i kamenog uglja u malim rudnicima je zanemarljiva, oko 550.000 t (ili oko 1,5%) [EPS-sait, Strategija 2015, Program ostvarivanja strategije]. Potrošačima u Srbiji je prodato 2007 godine 28.749 GWh električne energije. « hide
  Symposium Session: Energy resources and sustainable development | Energetski resursi i održivi razvoj