Pressurised Water Reactors PWR

I0.6.8.I Cladding failure in oxide fuel pins of nuclear reactors. The long-term operational performance of nuclear fuel pins is critically governed by the reactions that occur in the gap between the fuel and its cladding. Ball et al. (1989) examined this for the cases of (1) Zircaloy-clad pellets of U02+, in a pressurised water reactor (PWR) and (2) stainless-steel-clad pellets of (U, P)02+, in a liquid-metal-cooled fast-breeder reactor (LMFBR). In particular they were interested in the influence of O potential on Cs, I, Te and Mo and the effects of irradiation on the gaseous species within the fuel-clad gaps. 

Or to use a design in which the core of a conventional pressurised water reactor (PWR) is enclosed within a vessel of boronated water that will flood the core if pressure is lost there is no barrier between the core and the pool of water, which in case pressure in the primary system is lost will shut the reactor down and continue to remove heat from the core by natural circulation. It is calculated that in an accident situation, replenishing of cooling fluid can be done at weekly intervals (in contrast to hours or less required for current light water reactor designs) (Harmerz, 1983 Klueh, 1986). 

The environmental measurements around French nuclear power plants are described by Le Corre and Bourcier (1996). Electricite de France generates 75% of its electricity in nuclear power plants with pressurised water reactors (PWR). These plants comprise 34 units of 900 MW and 20 units of 1300 MW, the first of which was connected to the grid in 1977, and the last in 1993. Three other units of 1400 MW are under construction. The environmental measurements are performed in two complementary ways ... 

The purpose of this section is to compare the features of the RBMK reactor operated at Chernobyl with reactor types pertinent to the UK. It will be recollected that the RBMK covers a large number of reactors and the comparisons made are indeed with Chernobyl No. 4. The UK reactors covered are in three classes the commercial reactors now built and operated or in commission (Magnox and Advanced Gas-cooled Reactor (AGR)) the prototype Steam Generating Heavy Water Reactor (SGHWR) and Prototype Fast Reactor (PFR) that have comparable performance to commercial reactors and the proposed Pressurised Water Reactor (PWR) or Sizewell B design which, it... 

This section provides a comparison of power reactors built in the UK with the Soviet RBMK. But it is worth recollecting that, elsewhere in the world, other types of power reactors are in use. The most widely built reactor is the Pressurised Water Reactor (PWR) but the second is the Boiling Water Reactor (BWR), a light water reactor in which, like the RBMK, steam is generated in the core and passed to the turbines in a direct cycle. Light (i.e. ordinary) water is used as coolant and moderator. The Canadian industry has developed the CANDU series of reactors, with limited export to India, etc., which have many pressure tubes to retain the coolant, as in the British SCHWR and Soviet RBMK, but are heavy-water-cooled and moderated. 

Relative to Pressurised Water Reactors (PWR), this being the most common system in member states, there are working groups on ... 

An experimental program was carried out in the Czech Republic, where Boiling crisis and Critical Heat Flux (CHF) were measured on the facilities that simulated the fuel assemblies of the former Soviet s Pressurised Water Reactors (PWR) WWER-440 and WWER-1000. The large part of experiments related to the CHF was performed at Skoda Plzen Ltd, Nuclear Machinery Plant. The NRI started a complex of research activities in this field at the end of seventies. 

Most of the discussions are presented here in the context of radionuclide behaviour during accidents at existing pressurised water reactors (PWRs) and boiling water reactors (BWRs). The basic principles in these discussions are applicable to all nuclear power plants. Readers may need to make some mental modifications of the specific details of the discussions to accommodate the imique features of other types of plants such as gas-cooled reactors, CANDU t5q)c reactors and RBMK reactors. 

The Westinghouse APIOOO is an advanced and passively safe pressurised water reactor (PWR) with an output capability of 1117MWe (at nominal site conditions) and an expected service life of 60 years. Its design includes passive safety features not present on the Generation-2 plants in service today, and extensive plant simplifications to enhance nuclear safety and facilitate the constmction, operation and decommissioning of the plant. This chapter presents the following information ... 

The design, testing, start-up and operating experience from previous pressurised water reactor (PWR) plants is utilised in the development of the initial pre-operational and start-up test programme for the APIOOO plant. This will include any lessons learnt from the commissioning of... 

The APIOOO safety systems are located inside the containment and shield building, and postaccident fluid is not re-circulated outside containment. Compared to traditional pressurised water reactor (PWR) designs, this greatly limits the extent to which post-accident contamination is spread. The need for operator actions post-accident has been greatly reduced. Those few that required actions have been studied with respect to radiation exposure, as shown in the EDCD, Section 12.3 (Reference 12.1). 

Boiling Water Reactors (BWR), Pressurised Heavy Water Reactor (PHWR) and Pressurised Water Reactor (PWR)... 

The analytical and design tools thus available in this text have made it possible to investigate fairly accurately the safety margins of other vessels adopted for pressurised water reactors (PWR), boiling water reactors (BWR) and fast breeder reactors (FBR). 

The use of nuclear energy in the production of electrical power involves substantial structural systems comprised of pressure vessels that house the reactor. Most of the light water (LWR) and pressurised water reactors (PWR) in... 

One is to produce the steam inside the reactor itself — a boiling water reactor (BWR). A second is to use water under pressure as the coolant and then transfer the heat to water in a secondary circuit, which will then become steam and drive the turbines. This is a pressurised water reactor (PWR). The cooling water does not boil, even though it will be in temperatures much above lOO C (typically as much as 315°C), as it is kept under very high pressure. These are not the only possibilities for light water reactors various design studies were even made at Harwell for steam-cooled reactors. ... 

By 1952, Harwell and Risley had started to look at other types of reactor systems, and more possibilities were beginning to emerge. Apart from the gas-cooled reactor, there were effectively two other systems which might be suitable for submarine use — either a liquid metal-cooled reactor or some form of pressurised water reactor (PWR). 

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