The editors are happy to present the twentieth volume in the review series Advances in Nuclear Science and Technology. Lahey and Drew, our first authors, present a concise development of the equations for two-phase flow, essential to the understanding of normal and, even more, accidental behavior in water-cooled reactors. The commitment to the PWR in Europe (now joined by England in this respect) and the aftermath of Chernobyl in the U.S.S.R. put continuing emphasis on the need for good understanding of two-phase phenomena to provide good modelling. The second review, by Downar and Sesonske, of light water reactor fuel modelling, follows this LWR interest and emphasises a current major economic interest: how to get the most out of fuel. Recollecting that the capital cost of nuclear power is high, it is easy to overlook the fact that in the lifetime of a plant as much money is spent on fuel as capital. Optimization is worthwhile. The U.S. scene still does not practice recycling whereas the European scene does. Now that the United Kingdom is building its first (commercial) light water reactor, the linear modelling of burnup exploited by the second authors will prove even more useful, although previously exploited for advanced gas-cooled reactors. If the U.K. is behind in this respect, the recycling undertaken by France and England has led to trial use of plutonium in thermal reactors but, even more, the availability of plutonium for fast reactors.

Inhalt

The Three-Dimensional Time and Volume Averaged Conservation Equations of Two-Phase Flow.- I. Introduction.- II. Spatial Averaging.- III. Conservation Equations.- IV. Time-Averaging.- V. Interfacial Jump Conditions.- VI. Transformed Equations.- VII. Closure and Constitutive Equations.- VIII. One-Dimensional Conservation Equations.- IX. System Classification.- X. Drift-Flux Techniques.- XI. Mixture Models.- References.- Nomenclature.- Light Water Reactor Fuel Cycle Optimization: Theory Versus Practice.- I. Introduction.- II. LWR Fuel Cycle Optimization Theory.- III. LWR Core Reload Design Practice.- IV. Theory Versus Practice.- References.- The Integral Fast Reactor.- I. Introduction.- II. Design Goals for the Next Generation Nuclear Power.- III. Passive Inherent Safety.- IV. Fuel Cycle Closure.- V. Plant Capital Cost.- VI. Operability and Reliability.- VII. Technology Development Status.- VIII. Future Development Path.- References.- Indoor Radon.- I. Introduction.- II. Terminology of the Radon Problem.- III. Radon Sources, Measurements, and Levels.- IV. Lung Dosimetry Models.- V. Risk Estimation Methods.- VI. Cancer Rates and Radon Exposure.- VII. Comparison of Radon Doses with Doses From Other Sources.- VIII. Summary and Discussion.- References.