NUMERICAL INVESTIGATION OF THE DEFORMATION OF A CONTROL ROD SYSTEM DURING A DROP IMPACT SCENARIO IN A TYPICAL MATERIAL TESTING REACTOR

摘要

The control rod drop analysis is very important for safety analysis. A mathematical model of the control rod for the ETRR-2 reactor is presented. A computer program by the Engineering Equation Solver has been developed for investigation of the impact force and the final dropping velocity of the rod. Also, buckling deformation stresses have been simulated using commercial software, ABAQUS/CAE release 6.14-5. This paper describes the theoretical results required to obtain the von Mises stress at maximum impact force during the control rod drop. The control rod velocity after the rod reached the reactor core bottom has been predicted which reached up to 3.8 ms(-1) after a drop time equal to 0.41 s at the end of the reactor core height. The results showed that the maximum and minimum von Mises stresses are 90 MPa and 6.345 MPa at maximum and minimum impact force of 6625 N and 755.73 N, respectively.