DEVELOPMENT OF PLANT SYSTEM THERMAL HYDRAULICS NEUTRONICS COMPUTER CODE ATMIKA LWR FOR KUDANKULAM VVER 1000 MWe REACTOR
29th Symposium of AER on VVER Reactor Physics and Reactor Safety (2019, Energoland, Mochovce NPP, Slovakia)
advances in spectral and core calculation methods
Abstract
The system thermal hydraulics neutronics computer Code “ATMIKA-LWR” is developed with the objective to perform indigenous safety analysis of VVER 1000 MWe reactors of Kudankulam Nuclear Power Plant (KKNPP) of India. The code is developed for analysis of various Postulated Initiating events (PIEs) which include Anticipated operational Occurrences (AOO), Design Basis Accident (DBA) and for Design Extension- A (DEC–A) events of VVER 1000 Reactors.
The code simulates the overall thermal hydraulics of the plant along with integrated control systems viz. Primary pressure control, Steam Generator (SG) pressure and level controls, Turbine Governor controls, Reactor control system along with Emergency protection & Preventive Protection, Safety Injection and other systems & automatic actuation logics. Presently the computer code is coupled with point kinetics model and work is going on for its coupling with 3D kinetics for space effects.
The various simulation studies performed and results of AOOs such as RCP trip, Turbine trip, Reactor trip, Load rejection, TDFP trips etc. are compared with KKNPP Commissioning Test results. The unplanned plant transient events such as 2 TDFP trip with failure of starting of 1 EDFP causing emergency protection trip of KKNPP are simulated using the computer code. The simulation of SG tube rupture event with primary and secondary cooling by systems such as SGECD and EBIS is completed and results are compared with published results of VVER 1000 reactors. This paper presents the modelling aspects and results of simulation studies of 2 Adjacent RCP Trip using the computer code.