PAPERS SELECTED FOR THE SYMPOSIUM

• NUMERICAL SIMULATION OF POOL BOILING PROCESS

  Milada Pezo - Institut za nuklearne nauke VINČA, Laboratorija za termotehniku i energetiku, Vlada Stevanović - Mašinski fakultet, Univerziteta u Beogradu

  Abstract Text

  Predictions of nucleate boiling mechanisms and burnout conditions are very important in thermal-hydraulic safety analyses in steam generators. Mathematical modelling and numerical simulation of these phenomena require a treatment of vapour-liquid two-phase mixture on the macro level, as well as... show full text »
  Abstract Text

  Predictions of nucleate boiling mechanisms and burnout conditions are very important in thermal-hydraulic safety analyses in steam generators. Mathematical modelling and numerical simulation of these phenomena require a treatment of vapour-liquid two-phase mixture on the macro level, as well as on the micro level, such as bubble rise and departure at the heating surface. A mathematical model of pool boiling was developed in this paper, with water-steam as coolant. Three-dimensional two-phase flow is modelled by the two fluid model. Interface transfer processes are calculated by the closure laws. Numerical experiments have been performed under high heat fluxes, which lead to the boiling crisis. Boiling crisis occurs when the heated surface is covered with vapour bubbles, and these bubbles form a barrier that hinders the replenishment of the heated wall by the pool water. Under these conditions the wall dryout occurs. The thermal transient behaviour of the heated wall is also the subject of this paper. A large increase of the wall temperature is predicted in case of dryout occurrence. « hide
  Symposium Session: Thermal, hydro, wind and other Power Plants | Eksploatacioni problemi termo, hidro, vetro i drugih elektrana