No abstract available

[en] A process is submitted for superheating the pressurised steam generated in a light water nuclear reactor in which the steam is brought to 340⁰C at least. This superheated steam is used to operate a turbo-generator unit. The characteristic of the process is that an exothermal chemical reaction is used to generate the heat utilised during the superheating stage. The chemical reaction is a mechanisation, oxidation-reduction or hydrogenation reaction

[en] A process is described for resuperheating steam coming from the high pressure stage of a turbine fed by a steam generator, itself heated from a base thermal source. The resuperheating is done by desuperheating at least a part of the steam coming from the generator, taken from the inflow of the turbine high pressure stage, the desuperheated steam being condensed, partially at least, in a condensation exchanger forming a preliminary resuperheater

[en] The atomic-scale details during melting of a surface-free Lennard-Jones crystal were monitored using molecular dynamics simulations. Melting occurs when the superheated crystal spontaneously generates a sufficiently large number of spatially correlated destabilized particles that simultaneously satisfy the Lindemann and Born instability criteria. The accumulation and coalescence of these internal local lattice instabilities constitute the primary mechanism for homogeneous melt nucleation inside the crystal, in lieu of surface nucleation for equilibrium melting. The vibrational and elastic lattice instability criteria as well as the homogeneous nucleation theory all coincide in determining the superheating limit

No abstract available

[en] The concept of the critical nucleus is the basis of the homogeneous nucleation theory which enables the upper limit of a superheat to be calculated. Only nucleus formation is considered. It is as if nuclei that reach the critical dimensions are removed from the system and replaced by an appropriate mass of liquid. The theory does not give any information concerning the dynamics of bubble growth either. Nevertheless, some researchers use the concept of the critical nucleus as the initial condition in a descritpion of the bubble growth in superheated liquid. A bubble begins to grow after the disturbance of the balance, when the pressure difference exceeds the surface tension. According to this scheme, the initial bubble growth results from the fact that the vapor pressure in the bubble is higher than that in the surrounding liquid

[en] The bubble growth rate and microlayer behavior were simultaneously visualized for an isolated boiling regime of saturated water. The increase rate of the bubble volume dropped sharply when the microlayer was totally depleted. However, the contribution of the superheated liquid layer evaporation to the bubble volume increase was comparable to or even higher than that of the microlayer evaporation during the time when the microlayer evaporation was active. The microlayer under the coalesced bubble was much thicker than that under single isolated bubble. (author)

No abstract available

[en] We perform simulations of both colloidal suspensions and planar arrays systems of superheated superconducting granules. Transitions induced by an increasing external field appear in both situations as an ordering mechanism. Concentrated planar arrays present an interval of external field for which no transitions are produced. These effects can be interesting in applications for superheated superconducting granule detectors

[en] In reactor component materials for use in a nuclear superheating reactor, a high temperature and steam resistant alloy is coated on the surface of a cladding tube main body and the component main body comprising an irradiation embrittling alloy. Accordingly, both of the irradiation embrittlement resistance and high temperature and steam resistance can be provided. As a result, it can be used even in a circumstance undergoing irradiation of extremely great amount of fast neutrons and exposed to steam corrosion, thereby enabling to remarkably improve durability. (T.M.)