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971.
In this paper, we propose a new lattice Boltzmann model for the compressible Euler equations. The model is based on a three‐energy‐level and three‐speed lattice Boltzmann equation by using a method of higher moments of the equilibrium distribution functions. In order to obtain second‐order accuracy, we employ the ghost field distribution functions to remove the non‐physical viscous parts. We also use the conditions of the higher moment of the ghost field equilibrium distribution functions to obtain the equilibrium distribution functions. In the numerical examples, we compare the numerical results of this scheme with those obtained by other lattice Boltzmann models for the compressible Euler equations. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
972.
本文介绍一种以加速组元为终端负载的纳秒脉冲功率系统。获得的加速间隙电压为350kV,90ns(半高宽),波形上升时间为30ns;Blumlein主开关工作电压大于280kV,抖动小予1.5ns(均方根值)。对同轴场畸变开关性能的进一步改善作了必要的讨论,提出了用等场强原则偏置触发极,比通常采用自然中位面方法,可使开关工作电压提高8.7%。 相似文献
973.
974.
The corrosion behavior and surface morphology of Ni–SiC composite coatings produced by electrodeposition with the aid of magnetic
field were studied. The results of the electrochemical analysis including polarization resistance and potentiodynamic polarization
curves showed that a magnetic field of 0.1 T could significantly improve the corrosion resistance of the composite. The electrochemical
impedance spectra revealed that a passive layer was formed on the surface of the Ni–SiC coating with the magnetic field. The
microstructures of electrodeposited Ni–SiC composite coatings were also examined. More SiC particles were found to be incorporated
into the coating with the presence of magnetic field, which was considered to be one of the reasons for the enhancement of
corrosion resistance as SiC particles were reported to be corrosion inhibitors.
Contribution to special issue “Magnetic field effects in Electrochemistry” 相似文献
975.
The theoretical hybridization model of Vega is adapted to the tetrahedral environment around the nitrogen nucleus in eleven
amino acids to estimate the orbital occupation numbers using the experimental values of the quadrupole coupling constant and
asymmetry parameter of14N quadrupole resonance and the results are discussed. 相似文献
976.
The crack tip fields of stress, strain and damage for concrete under both antiplane shear and plane strain conditions are investigated based on the damage model proposed by Mazars and Lemaitre [2]. The structures of near tip fields obtained are similar to those for an elastic-perfectly-plastic material. It has been found that damage boundaries can not be determined by the near-tip analysis due to the discontinuities of stresses on the damage boundaries induced by the damage model used in the present paper.The Project is Supported by National Natural Science Fundation of China. 相似文献
977.
978.
Necessary and sufficient conditions are given for the existence of the general solution, the centrosymmetric solution, and the centroskewsymmetric solution to a system of linear matrix equations over an arbitrary skew field. The representations of such the solutions of the system are also derived. 相似文献
979.
采用一台高重频、快上升沿纳秒脉冲电源作为激励源,对典型的双电极合成射流激励器进行放电,通过粒子图像测速法(particle image velocimetry,PIV)测量放电实验中激励器稳定流场特性以及发展速度.分析实验结果发现,随着重复频率的提高,合成射流的平均发展速度也随之增大,1 kHz时的平均速度最高达到28.28 m/s,并在单脉冲能量远低于微秒脉冲的情况下,实现了更快的稳态流场控制,表明高重复频率下,更多次数的脉冲放电可提高激励总能量,有效地弥补纳秒脉冲单脉冲输出能量不足的缺点.而且频率越高,流场发展速度越快,说明高重频工作模式会对输出总能量有补偿作用. 相似文献
980.