Category Archives: NUCLEAR ELECTRIC POWER

EXPERIMENTAL IMPACT FACILITIES

The following experimental impact facilities at AEEW were typical of those involved in collaborative agreements with French and German companies. As explained in Section 6.2 the provision of micro-concrete which accurately replicates the bonding between actual concrete, aggregate and steel armatures is of paramount importance. Because commercial suppliers were considered unable to meet the required standards of consistency, a small […]

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TEMPERATURE AND OTHER OPERATIONAL FEEDBACK EFFECTS

With material power production, temperatures and other phenomena change the effective multiplication constant K. Higher temperatures increase the vibrations of component nuclei and decrease their densities. One effect is to widen the effective resonance absorption bands of U-238. Because neutrons are slowed down by scattering in energy steps many times larger than these resonance widths, their non­fissile capture rates by […]

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Molten Fuel Coolant Interactions: Analyses and Experiments

5.1 A HISTORY AND A MIXING ANALYSIS A potential explosion when molten reactor fuel mixes with its vaporizable coolant is an example of a more general phenomena. Outside the nuclear industry other highly destructive thermal detonations involve iron + water [186,187]; aluminum + water [188]; liquefied natural gas + seawater [189], soda ash + water [190]; coal tar + water […]

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HYDROELECTRICITY

Some 715 GW of hydroelectric power are already installed worldwide, and in 2006, it supplied 20% of the global electricity demand and 88% of that from all renewable sources [4]. Large schemes of more than about 30 MW involve the construction of a convex dam across a deep river gorge whose sides and bottom must be geologically sound. In addition, […]

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COMPUTATIONAL TECHNIQUES AND AN AIRCRAFT IMPACT

Several correlations of experimental data are available for predicting the damage to simple reinforced concrete panels from the impact of hard flat-nosed cylindrical steel billets. Scabbing damage corresponds to dislodgement of a portion of the target’s rear face, and perforation has its usual connotation. More than 150 experimental results are available for comparison against these formulae. Neilson [286] estab­lishes that […]

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REACTOR CONTROL, ITS STABLE PERIOD, AND RE-EQUILIBRIUM

Section 2.4 describes how power production changes the effective multiplication factor of a nuclear reactor so that K = K (N) (2.31) As a result equation (2.26) is non-linear. However, for control analysis it is sufficient to examine this equation for small perturbations about an operating point for which the effective multiplication factor is a constant derived from neutron diffusion […]

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SOLAR ENERGY

Photoelectricity was discovered by Hallwachs [16] in 1888, and its quantum mechanical analysis was provided by Einstein in 1905. However, the necessary research toward viable electrical power units actually began in 1954 with transistor development by Bell System Laboratories NJ. Solar cells for this purpose are now [17] series — connected arrays of p-n junctions in ribbon polycrystalline silicon which […]

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Natural Circulation, Passive Safety Systems, and Debris-Bed Cooling

7.1 NATURAL CONVECTION IN NUCLEAR PLANTS Following the immersion of a heated surface in a fluid, molecular heat conduction raises local temperatures and thereby reduces fluid densities [208,209]. Buoyancy forces then lift these localized lighter fluid packets to induce a continuous laminar or turbulent flow called natural circulation or natural convection. Industrial research on natural con­vection began in the 1930s […]

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Some Power Station and Grid Control Problems

3.1 STEAM DRUM WATER-LEVEL CONTROL Grid-connected power stations are operated in either decoupled or coupled mode [80,117], which describes the form of their response to grid frequency variations1 from changes in network demand. These alternatives are illustrated in Figures 3.1 and 3.2 where C1 (s) and C2 (s) represent controller transfer functions. By creating strict limits on steam plant temperature […]

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