ISRM Symposium - Rock Mechanics: Caverns and Pressure Shafts (International Society for Rock Mechanics). Volume 2: Pressure Tunnels/Tunneling Machines/Underground Storage, Aachen, West Germany
The paper discusses a few points arising in the generation and use of Homogenized Diffusion Theory (HDT) constants when they are obtained from one-directional transmission/reflection matrices. This paper shows ha, HDT constants me generated if a P1 angular distribution is chosen for the injected neutrons, shows the explicit calculation of such constant consistent with a one meshpoint per cell (e.g., bundle cell) discretization, and demonstrates the method for heavy and light water reactor lattices.
A mathematical model is developed in this paper for the reliability evaluation of an electrical power supply system utilizing multiple standby generator units. The evaluation includes the availability of standby generator units in the dormant state, the probability of success or failure during the transition from the dormant state to the operating state and the running reliability of the system in the operating state. The state space approach is used in the development of the model. A testing procedure is proposed to establish the running reliability of the standby units. The model can be applied to both the system design and the evaluation of the system reliability during operation.
This paper considers the use of low-enriched uranium fuel in a 842 MWe CANDU-PHW (Pressurized Heavy Water) reactor that was originally designed for natural uranium fuel. The technical feasibility and the economics of such a substitution are discussed. It is concluded that 0.9 wt% enriched fuel, coupled with a fuelling scheme of 2-bundle-shift in the inner core region and 4-bundle-shift in the outer core region, is the most attractive option. Technically, it is feasible, and economically, for a 30 year reactor life starting from 1983, it could realize a capitalized cost savings in the order of 50 M$/reactor (in 1980 dollars, present-worthed to 1980).
Unit 1 of Pickering NGS- A, Canada's first commercial nuclear power station, entered service in 1971. It features digital computers controlling the nuclear units - the first such commercial application. After approximate l y 55 reactor years and over 100 computer years of operation, Ontario Hydro is undertaking a major upgrade of the Pickering- A control computers. The current IBM 1800 computers will be connected to a distributed system of microcomputers which will take over all the major operator-interface and annunciation functions. The upgrade will provide a modern, integrated, operator-machine interface, plus straightforward system expansion and eventual IBM 1800 replacement.
