共查询到20条相似文献,搜索用时 15 毫秒
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自适应光学系统的数值模拟:动态控制过程和频率响应特性 总被引:3,自引:0,他引:3
对自适应光学系统的动态控制过程进行了数值模拟。与自动控制理论的解析分析相比,动态控制过程的数值模拟有其优越性。系统的频率响应特性与动态控制性能密切相关,对自适应光学系统的频率响应特性也进行了数值模拟。模拟计算的结果与实验测量结果符合得很好。还实现了多频率成份的同时计算,可以大大提高计算效率。其结果与单频率结果只在低频下有小的差别,可以满足得到带宽和裕量等参数的实用要求。将频率响应特性的模拟计算与长时间曝光斯特列耳(Strehl)比的数值模拟结合,可得到对自适应光学系统性能的有效评估。 相似文献
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Thermoacoustic prime movers can generate pressure oscillation without any moving parts on self-excited thermoacoustic effect. The details of the numerical simulation methodology for thermoacoustic engines are presented in the paper. First, a four-port network method is used to build the transcendental equation of complex frequency as a criterion to judge if temperature distribution of the whole thermoacoustic system is correct for the case with given heating power. Then, the numerical simulation of a thermoacoustic-Stirling heat engine is carried out. It is proved that the numerical simulation code can run robustly and output what one is interested in. Finally, the calculated results are compared with the experiments of the thermoacoustic-Stirling heat engine (TASHE). It shows that the numerical simulation can agrees with the experimental results with acceptable accuracy. 相似文献
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E. V. Aksenova D. I. Kokorin V. P. Romanov 《Journal of Experimental and Theoretical Physics》2012,115(2):337-345
Multiple scattering of light by the fluctuations of the director in a nematic liquid crystal (NLC) aligned by a magnetic field is considered. A peak of coherent backscattering is calculated by numerical simulation. Since the indicatrix of single scattering for a liquid crystal (LC) is known exactly, the calculations are carried out without any simplifying assumptions on the parameters of the liquid crystal. Multiple scattering is simulated as a random walk of photons in the medium. A peak of coherent backscattering in such a medium is very narrow; therefore, the so-called semianalytical method is applied. The parameters of the backscattering peak obtained by numerical simulation are compared with the available experimental data and with the results of analytical approximations. It turns out that the experimental data are in good agreement with the results of simulation. The results of numerical simulation adequately describe the anisotropy and the width of the backscattering peak. 相似文献
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提出一种在Matlab/GUI环境下设计的晶体硅太阳电池数值模拟软件,通过光生少数载流子连续性方程建立了单晶硅N+/P/P+结构太阳电池的物理模型。通过引进有效迁移率和有效少子扩散长度概念,并考虑多晶硅中晶界复合后,实现了对单晶硅、柱状多晶硅太阳电池的开路电压、短路电流、填充因子、转化效率、串并联电阻等电池性能的参数指标的数值模拟。程序模拟结果通过数值和图形两种方式输出,模拟结果与实验结果接近,能够为晶体硅太阳电池的设计与制备起到较好的指导作用。本程序对于以N型材料为衬底的晶体硅太阳电池同样适用。 相似文献
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A Lagrangian compatible radiation hydrodynamic algorithm and the nuclear dynamics computing module are developed and implemented in the LARED Integration code, which is a radiation hydrodynamic code based on the 2-D cylindrical coordinates for the numerical simulation of the indirect-drive Inertial Confined Fusion. A number of 1-D and 2-D ignition implosion numerical simulations by using the improved LARED Integration code (ILARED) are presented which show that the 1-D numerical results are consistent with those computed by the 1-D radiation hydrodynamic code RDMG, while the simulation results of the 2-D low-mode radiative asymmetry and hydrodynamic instability growth,according to the physical analysis and anticipation, are satisfactory. The capsules driven by the sources from SGII experiments are also simulated by ILARED, and the fuel shapes agree well with the experimental results. The numerical simulations demonstrate that ILARED can be used in the simulation of the 1-D and 2-D ignition capsule implosion using the multi-group diffusion model for radiation. 相似文献
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炸药条加载圆柱壳的数值模拟(Ⅱ):解耦分析与实验验证 总被引:1,自引:0,他引:1
根据已报道的二维流固耦合数值模拟结果,建立了经缓冲橡胶整形后的单炸药条载荷模型。将炸药条载荷叠加后直接施加在圆柱壳表面,进行二维解耦模拟,得到了与流固耦合模拟基本吻合的应力结果。在此基础上,对19条炸药条加载Φ265 mm×380 mm圆柱壳进行了三维解耦模拟,并采用相同状态的实验予以验证。结果表明,特征点应变响应吻合较好,验证了炸药条加载圆柱壳解耦数值模拟的有效性,为大量工况数值分析、提高建模和计算效率奠定了基础。 相似文献
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K. Kusaiynov N. K. Tanasheva L. L. Min’kov B. R. Nusupbekov Yu. O. Stepanova A. V. Rozhkova 《Technical Physics》2016,61(2):299-301
An air flow past a single triangular sail-type blade of a wind turbine is analyzed by numerical simulation for low velocities of the incoming flow. The results of numerical simulation indicate a monotonic increase in the drag force and the lift force as functions of the incoming flow; empirical dependences of these quantities are obtained. 相似文献
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应用基于投影算法的不可压缩光滑粒子动力学(incompressible smoothed particle hydrodynamics, ISPH)法对黏性液滴变形过程进行了数值仿真. 对于张力失稳导致的粒子非物理簇集问题, 采用粒子移位技术加以解决. 为了验证本文ISPH 算法的精度和稳定性, 分别模拟了圆形黏性液滴的拉伸变形过程以及方形液滴的旋转变形过程, 得到了不同时刻液滴内部的压力变化特征, 准确地捕捉了液滴自由面演化过程, 并将数值计算结果与文献中的解析解进行了比较.分析结果表明, 基于投影算法的不可压缩光滑粒子动力学方法结合粒子移位技术, 能够有效地模拟黏性液滴变形过程, 可以得到精确和稳定的结果.
关键词:
不可压缩光滑粒子动力学
黏性液滴
自由面流动
数值仿真 相似文献
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本文采用高分辨率格式和多块多网格方法求解雷诺平均Navier-Stokes方程,数值模拟多排叶片内的三维粘性流动;使用数值激盘模拟叶片排的存在,研究叶片排与非轴对称排气部件之间的相互作用以及复杂的内部流动。文中描述了数值方法,给出了NASA透平导叶和单级透平内部流场的数值结果及其与相应实验结果的对比,也给出了多级透平内部流场的数值结果,以及透平与排气部件之间的耦合流场的结果。 相似文献
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A semi-automatic and active control of T-S waves and oblique waves in a transitional flat plate boundary layer is carried
out in a wind-tunnel experiment and a numerical simulation. An array of piezo-ceramic actuators attached on a surface is used
to generate counter waves that cancel the incoming instability waves. The actuator’s operating amplitudes and phases are successively
updated using the velocity fluctuations monitored downstream by a rake of hotwires. Experimental results show that the system
is effective in weakening these waves when their inclination angles are less than 15 degrees. However, the system encountered
difficulty in controlling the waves of large inclination angles. In the numerical simulation, it is shown that the control
can be accomplished much easier. The numerical results show that controllability of the large inclination angle waves can
be improved by shortening the spanwise length each actuator piece. The danger of pursuing this kind of research solely by
a numerical simulation is pointed out. 相似文献
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本文将贴体坐标用于具有复杂形状的船型体煤粉燃烧器的三维流场数值模拟中,建立了在贴体坐标下的总体质量校正方程。计算结果令人满意。同时,对存在的问题作了进一步讨论。 相似文献
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本文使用1(2/2)维电磁相对论粒子程序对自由电子激光进行计算机模拟。在线性段,计算机模拟与用解析理论计算的增长率符合很好。与没有轴向引导磁场的自由电子激光相比,加一弱轴向引导磁场时,Wiggler场的强度可降得较低。加一强轴向引导磁场时,波能量达到饱和水平所需时间较短。 相似文献
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为研究聚变堆氚增殖包层中液态金属湍流磁流体动力学(MHD)效应,开发了一种新的准二维单方程
MHD 湍流模型,并进行了相关数值模拟程序的编制及验证。对于矩形管道中的准二维 MHD 湍流流动,三维流
动主要发生在哈德曼层中,中心的主流区呈现出二维流动。为了反映这种特殊的流动特征,新湍流模型在标准 k-ε
模型的基础之上去掉了传统的耗散项,代之以电磁耗散项来模拟湍流 MHD 效应。同时,采用 Bradshaw 假设来对
湍流涡粘系数进行模化。为验证该湍流模型是否合理,编制了相关数值模拟程序,并利用直接数值模拟(DNS)结
果对该程序进行了校正,数值模拟结果与 DNS 结果吻合较好。计算结果表明,该湍流模型可应用于聚变堆液态
包层 MHD 湍流流动的数值模拟。 相似文献
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《Journal of computational physics》2003,184(1):163-191
We report on the numerical simulation of a two-fluid magnetohydrodynamics problem arising in the industrial production of aluminium. The motion of the two non-miscible fluids is modeled through the incompressible Navier–Stokes equations coupled with the Maxwell equations. Stabilized finite elements techniques and an arbitrary Lagrangian–Eulerian formulation (for the motion of the interface separating the two fluids) are used in the numerical simulation. With a view to justifying our strategy, details on the numerical analysis of the problem, with a special emphasis on conservation and stability properties and on the surface tension discretization, as well as results on tests cases are provided. Examples of numerical simulations of the industrial case are eventually presented. 相似文献