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Liu L.,North China Electrical Power University | Liu L.,State Nuclear Power Software Development Center | Lu D.,North China Electrical Power University
Nuclear Engineering and Design | Year: 2012

Further experiments and theoretical analysis were performed to investigate mechanism of the large-amplitude and narrow-band vibration behavior of a flexible flat plate in a rectangular channel. Test plates with different thicknesses were adopted in the FIV experiments. The natural vibration characteristics of the flexible flat plates in air were tested, and the added mass theory of column was used to analyze the flexible flat plates' natural vibration characteristics in static water. It was found that the natural vibration frequency of a certain test plate in static water is approximately within the main vibration frequency band of the plate when it was induced to vibrate with the large-amplitude and narrow-band in the rectangular channel. It can be concluded that the harmonic between the flowing fluid and the vibrating plate is one of the key reasons to induce the large-amplitude and narrow-band vibration phenomenon. The occurring condition of the phenomenon and some important narrow-band vibration characteristics of a foursquare fix-supported flexible flat plate were investigated. © 2012 Elsevier B.V.

Zhang L.,CAS Institute of Mechanics | Zhang L.,State Nuclear Power Software Development Center | Li Z.-D.,CAS Institute of Mechanics | Li K.,CAS Institute of Mechanics | And 2 more authors.
Journal of Computational Multiphase Flows | Year: 2014

Numerical simulation of single bubble pool boiling process including transient thermal response of solid wall is performed using the ghost fluid method and the level set method for the sharp interface representation. The results show that non-physical initial condition in the numerical simulation deeply affects the process of bubble growth, and then multi-cycle simulation is necessary to eliminate its influence. It is shown by the present results that two nucleate criteria, i.e. constant waiting time and constant nucleate superheat, for determining the appearance time for the subsequent bubble lead to the same quasi-steady process of bubble growth if they are matched with each other. A periodically expanding and receding thermal "hollow" can be observed inside solid wall underneath the growing bubble. The recovery of the temperature on the nucleate site and the thermal boundary layer near the heating surface is influenced by transient heat conduction inside solid wall, which can affect evidently bubble thermal dynamics and heat transfer.

Zhang L.,CAS Institute of Mechanics | Zhang L.,State Nuclear Power Software Development Center | Li Z.-D.,CAS Institute of Mechanics | Li K.,CAS Institute of Mechanics | And 2 more authors.
Applied Thermal Engineering | Year: 2014

Using the Ghost Fluid Method for sharp interface representation, the complete single bubble pool boiling process including the transient thermal response of the solid wall is simulated numerically. Two level set functions are used for capturing the liquid-vapor-solid interfaces. Bubble dynamics and local heat transfer influenced by thickness and material parameters of the solid wall are analyzed at constant temperature on its bottom. For the same material and the same bottom temperature, growth time and departure diameter of bubble change slightly with the thickness. A clear local low-temperature region is produced inside the wall under the bubble base, which expands and recedes periodically with the movement of the three phase contact line. The movement of the local low-temperature region lags gradually comparing to that of the contact line with increasing thermal diffusivity of solid walls. Waiting time increases with decreasing thermal diffusivity of solid walls, resulting in thickened thermal boundary layer at nucleation, and then short bubble growth time and large departure diameter. © 2014 Elsevier Ltd.

Liu M.,State Nuclear Power Software Development Center
International Conference on Nuclear Engineering, Proceedings, ICONE | Year: 2013

In this paper, the influence of significant nuclear events on public attitude, and the reaction, i.e., public attitude on the development of nuclear industry have been studied. Though it has been widely known that nuclear is a type of clean, green and effective source of energy, due to the characteristics of nuclear, for most common people, they seldom pay attention to the nuclear power plants (NPPs) or the entire nuclear industry except NPPs are built near the residence of their own, or when some catastrophic failures occur. This fact leads to that when the public's attention is attracted to nuclear, the effects on their attitude to nuclear are often negative. Even if there is positive news about nuclear, in most cases, the public will still be worried and prudent. That is one of the reasons why though the nuclear power related techniques has been developing rapidly, in some countries the usage of nuclear power is still quite limited. In order to carry the development of nuclear power forward, to improve the public acceptance is as important as to improve nuclear related science and technology. This paper focuses on how the significant events related to nuclear influence the public acceptance, which will have direct or indirect effects on the development and/or policy of nuclear industry in a country, even the whole world. Additionally, this paper discusses possible and proper solutions to improve the public acceptance to NPPs and nuclear related techniques. Copyright © 2013 by ASME.

Chen M.-L.,China Nuclear Power Technology Research Institute | Lin J.-M.,China Nuclear Power Technology Research Institute | Bai W.,State Nuclear Power Software Development Center
Yuanzineng Kexue Jishu/Atomic Energy Science and Technology | Year: 2016

A three-dimensional computational fluid dynamic code CYCAS was developed for hydrogen safety analysis. The code solved three-dimensional, compressible and unsteady Navier-Stokes equations by the numerical method of implicit continuous Eulerian-arbitrary Lagrangian Eulerian. Multi-component mass conservation equations were solved to describe the diffusion and mixing phenomenon. A homogeneous equilibrium model was applied to model the phase change of water vapor in the fluid flow. For the phase change near the wall, the Chilton-Colburn empirical analogy was used. Algebraic and k-ε turbulence models were employed to model the turbulent flow. The turbulent jet experiment HYJET and the international standard problem ISP23 were simulated and analyzed for CYCAS validation. The computational results agree well with the experimental data. © 2016, Editorial Board of Atomic Energy Science and Technology. All right reserved.

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