Showing papers in "Nuclear Engineering and Design in 1983"

TL;DR: A review of the state of the art of two classes of vibration problems encountered in reactors and reactor peripherals is presented in this paper, where a historical perspective is given, in which milestone contributions that have advanced the state-of-the-art are highlighted.

TL;DR: In this article, a displacement-based finite element formulation for inviscid, compressible, small displacement fluid motions is examined, with the specific objective of calculating fluid-structure frequencies.

TL;DR: In this paper, a gap model was proposed to express gap closure during rise to power and the concept of critical void ratio was introduced for determination of the hard PCI (pellet-cladding interaction) onset condition.

TL;DR: In this paper, a series of high pressure, low heat and mass flux experiments were performed in a heated vertical rod bundle with internal dimensions similar to a PWR fuel bundle and the experiments showed that void fraction data could be fitted to a drift-flux equation with a constant drift-velocity.

TL;DR: In this paper, the shape memory effects of alloys are described in three dimensions by means of an extended classical theory of plasticity, and two temperature-dependent yield criteria are used which respond under different conditions.

TL;DR: In this paper, a multiaxial constitutive model for concrete in the temperature range up to 800°C is proposed, which is characterized as isotropic, elastic-viscoplastic-plastic in the compression region.

TL;DR: In this paper, an approximate constitutive model for creep and shrinkage at temperatures above 100°C, up to about 400°C is presented. But the model does not consider the effect of various constant temperatures on the creep rate and the rate of aging.

TL;DR: In this paper, reinforced concrete slabs are tested extremely stressed under the impact of highly deformable projectiles, and the results show a high sensitivity with respect to the load conditions, which are strongly influenced by the impact velocity as well as by the deformation behaviour of the projectiles.

TL;DR: In this paper, the authors proposed a defect reconstruction method using the flexible and fast electronic beam forming with phased arrays, where a reflecting point is represented as a short circular curve, the length of which is dependent upon beam width and system sensitivity.

TL;DR: In this paper, the exact solutions of the problems of heat flux and temperature determination on slabs are presented on the ground of the theory of thermoelasticity, and the approximate forms of the solutions are simplified significantly if the time step is sufficiently large.

TL;DR: In this article, the authors present a method of fuel rod thermal-mechanical performance analysis used in the FEMAXI-III code, which incorporates the models describing thermal-MEchanical processes such as pellet-cladding thermal expansion, pellet irradiation swelling, densification, relocation and fission gas release as they affect pelletcladding gap thermal conductance.

TL;DR: A mathematical model for the instability of tube arrays subjected to crossflow is examined in this paper, based on the fluid-force data for a pitch-to-diameter ratio of 1.33.

TL;DR: In this article, boundary integral equations for non-steady conduction problems of solids, subject to non-linear convective and radiation conditions on surfaces, were derived, modelled by non-conforming boundary elements, while domain integrals were evaluated within triangular cells.

TL;DR: In this paper, the authors investigated the contribution of flow oscillation on the decrease in critical heat flux (CHF) with forced convection under an oscillating acceleration condition and showed that in the high exit quality region deteriotation of CHF could almost wholly be attributed to the variation of inlet flow rate induced by motion.

TL;DR: In this paper, the authors examined a single plate bounded by two channels and determined the static plate deflection as a function of plate, channel and flow parameters, which is due to differences in pressure and flow velocity in the channels bounding the plate and also due to different channel dimensions caused by tolerance effects.

TL;DR: In this article, the exact solution of the title problem was solved using the classical theory of vibrations of beams and a tabulation of eigenvalues was presented as a function of some of the governing mechanical parameters.

TL;DR: In this article, the Barkhausen noise resulting from the irreversible movement of the Bloch walls in a ferromagnetic material was used to obtain information on the microstructural state of a material by means of non-destructive methods.

TL;DR: In this article, a finite element solution to the problems of stress distribution for cylindrical shells with circular and elliptical holes and also for normally intersecting thin elastic cylinders is given in the analysis.

TL;DR: The analytical results of blowdown characteristics and thrust forces were compared with the experiments, which were performed as pipe whip and jet discharge tests under the PWR LOCA conditions.

TL;DR: In this paper, the imperfection size distribution of pipe welds reported by Raussi and Tiainen was analyzed and a lognormal distribution and Weibull distribution were shown to be compatible with the data.

TL;DR: In this paper, a thorough numerical analysis of an identification process, that has been analytically described in the preceding paper in this issue, is presented, and the conclusions have shown some new aspects of the problem and are confirmed by brief additional analytical considerations.

TL;DR: In this article, a two component laser doppler velocimeter with polarized beams and frequency shift was used to measure the turbulent flow field for axial flow between the rods of a nine rod, square pitch rod bundle.

TL;DR: In this paper, the effect of liquid solidification on the heat transfer characteristics for laminar flow of a heat-generating fluid in a cooled circular tube is investigated analytically.

TL;DR: A methodology for the evaluation of a fire protection system in a nuclear power plant is described in this article, where a system of Monte Carlo simulation modules has been developed, divided into the four phases of fire scenario: ignition, detection, suppression and propagation.

TL;DR: In this paper, the flow recovery downstream of a sharp edged plate blockage of one subchannel for axial flow through a square-pitched, six-rod array has been investigated for a rod pitch to rod diameter ratio of 1.107.

TL;DR: In this paper, the authors discuss damage evaluation in structures and the desirability of periodic inspections, and they make use of expert opinion, and interactive rule-based system analysis.

TL;DR: This paper summarizes the latest developments in this area with emphasis on the versatile method of analysis based on a consideration of load coincidence, and establishes the validity and accuracy of this method by comparison with other methods and Monte Carlo simulations.

TL;DR: In this article, a computer program SOFIA-II was developed based on an analytical single droplet combustion model and a two-dimensional temperature and oxygen concentration distribution model in the vessel.

TL;DR: In this article, the effects on material degradation of both aging conditions and the oxygen concentration during a Loss-of-Coolant Accident (LOCA)-simulation were surveyed, and the results indicated that a realistic LOCA-simulation test should include an overpressure of oxygen gas representative of the postulated oxygen concentration expected during predicted LOCA.

TL;DR: In this paper, the interaction between buckling and ratchetting under cyclic additional loading is discussed for elastic-plastic structures, and it is shown that progressive plastic deformation can lead to the buckling of a structure as a consequence of the resulting additional displacement.