APPLICATION OF COMPUTER-BASED OPERATOR INSTRUCTION SYSTEM TO PLANT DIAGNOSIS ON FISSION-PRODUCT TRANSPORT AND RELEASE IN NUCLEAR-POWER PLANTS

A computer-based operator instruction system (COINS) for diagnosing fission product (FP) transport and release in nuclear power plant (NPPs) is applied to plant diagnosis in combination with the computational code 'SACHET', which evaluates the dynamic FP inventories in the multiple compartment system of pressurized water reactor (PWR) plants. The COINS can be described in the most general way as a computer-based information processing system which takes in plant data, processes it, and displays the results to the NPP's operating crew. Our major concern for the COINS is, however, not to evaluate general plant dynamics, but to monitor the distribution of the whole radioactive materials such as FP, and to diagnose that plant state in view of FP transport during the NPP's lifetime.