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1.
为了缩短对家用空调冷凝器的性能研究时间和开发新产品的周期,开发了冷凝器仿真程序。利用分布参数模型对家用空调冷凝器进行仿真计算,并设计建立了冷凝器实验装置,对仿真结果进行实验验证。对冷凝器进行了在不同风速,不同冷凝温度下的实验,进行分析得到实验结果。并将其与仿真程序的计算结果进行了比较。通过比较证明了仿真结果和实验结果总体变化趋势一致;在相同工况下,模拟换热量的数值比实验换热量要低7.7%~12%;由此验证了仿真程序的可行性。  相似文献   

2.
对变阻器在分压、限流电路中的负载特性进行了讨论,并对其调节灵敏度进行了分析,给出了实验结果,表明理论分析与实验结果较好的符合。  相似文献   

3.
应用三维LDA对同向射流模型燃烧室的流场进行测量,对结果进行了分析。应用k-ε湍流模型进行了数值计算,计算结果与实验结果在定性上是一致的。  相似文献   

4.
针对电磁耦合仿真结果的校验需求,建立了基于光纤电场传感器的验模测试实验系统,对某模型的仿真结果进行了近场耦合验模测试。初步实验结果表明,在一定区域内,测试结果与仿真结果呈现趋势性一致,并对部分区域与仿真结果不符合的原因进行了分析,为下一步仿真模型优化和测试方法手段改进奠定了基础。  相似文献   

5.
本文对圆筒形推拉式磁偶合器的磁力矩 ,进行了推导 ,对推导结果进行了分析。  相似文献   

6.
空气横掠波纹管束流动与传热性能的数值模拟   总被引:7,自引:0,他引:7  
本文应用层流模型和湍流模型的数值模拟方法,对空气外掠8排波纹管束时的流动与传热性能进行了研究,并将数值结果与实验结果进行了对比,结果表明:层流模型数值模拟结果较湍流更接近于实验值。同时,对两种模型的数值模拟结果拟合出了Nu-Re的关联式。  相似文献   

7.
在分析"热线法"测定气体热导率原理的基础上,以干燥空气为例对其热导率进行了测量,用"线性外推法"进行数据处理,并用Origin7.0软件对测量结果进行了数据分析,可快捷精确地获得测量结果。  相似文献   

8.
余建军  杨伯君 《光子学报》1997,26(4):345-348
对负啁啾脉冲在正常色散光纤中的频域特性进行了实验研究,并对实验结果进行了数值分析,实验和数值分析结果基本一致.  相似文献   

9.
喷动流化床的数值模拟研究   总被引:4,自引:0,他引:4  
本文借鉴 Cundall& Strack提出的碰撞模型,将欧拉方法和拉格朗日法结合起来,建立了喷动流化床气固两相流动的数学模型,在计算机上对试验台进行了模拟,探讨了床内颗粒的运动特征。按1:1的比例建立了喷动流化床的模型试验台并进行了试验,对模拟结果和试验结果进行了比较与分析。颗粒在喷动床内的运动特征,模拟结果都能够再现出来,模拟结果与试验结果取得了很好的一致性。  相似文献   

10.
本文用数值计算的方法对炽热平板点火问题进行了研究,并将计算结果与实验结果加以比较,在层流流动中与实验结果的吻合令人满意,在湍流流动中也进行了计算,并对结果加以了讨论。  相似文献   

11.
运用接触力学和圆环压溃强度理论对由V型槽固定的光子晶体光纤进行了受力分析。分别考虑了两种极限情况,以推导光纤中的应力分布。第一种情况假设光纤是完全由纯石英材料制成的内部均匀的实芯圆柱体;第二种情况是把光纤假设成一个空芯圆柱体。根据这两种极限情况推导出了光子晶体光纤受力后光纤内部的最大应力点位于平行于接触面的外层空气孔的附近。采用有限元方法验证了此结论,计算出了光子晶体光纤可能承受的最大压力,并给出了光子晶体光纤在V型槽中的应力分布和变形情况。  相似文献   

12.
We consider a model of convection in which five hydrodynamic modes interact. We show the existence of oscillations in which the sign of rotation of the rolls is periodically reversed. When the Rayleigh number is increased, these oscillations exhibit a sequence of period doublings which is not of the Feigenbaum type.  相似文献   

13.
The general theory of gauge fields is used to develop a theory of electrodynamics in which the fundamental structure is non-Abelian and in which the internal gauge field symmetry is O(3), based on the existence of circular polarization and the third Stokes parameter. The theory is used to provide an explanation for the Sagnac effect with platform at rest and in motion. The Sagnac formula is obtained by considering the platform in motion to be a gauge transformation. The topological phases can be described straightforwardly with non Abelian electrodynamics, which produces a novel magnetic field component for all types of radiation, a component which is proportional to the third Stokes parameter. The theory provides a natural explanation for the inverse Faraday effect without phenomenology.  相似文献   

14.
周恒  刘源俊 《大学物理》2003,22(5):31-33
介绍一自制的负载弦教具,5颗沿铀向充磁的圆柱状钐钴磁铁穿在细钓鱼线上,作为负载弦之负载质点,再以可调频率的交流电磁化马蹄形电磁铁,使得马蹄形电磁铁对圆柱状钐钴磁铁施与周期性的引力及斥力,启动负载弦的各个简正模式.此自制的负载弦教具可定量演示教科书中理论计算的结果.  相似文献   

15.
A classification is provided for the principal backscattering-enhancement mechanisms, which are divided into singleparticle and collective mechanisms, which, in turn, consist of geometrical mechanisms and mechanisms associated with phase coherence. A distinction is made between dynamic mechanisms, which appear in nearly all realizations, and statistical mechanisms, which are observed only after averaging.  相似文献   

16.
A problem of finding the energy of ground state of a quantum particle in a nanostructure with axial symmetry is considered. It is assumed that there is a point defect inside the nanostructure, which is given by δ-potential. A transcendent equation, which defines the lowest level of energy of the particle, is obtained. Corresponding formulas are used for calculation of the threshold frequency of interband absorption of light in semiconductor nanocrystals, which are dispersed in transparent dielectric matrix. Absorption spectrum edge dependence on location and power of δ-potential is obtained. It is shown that the effective length of the cylindrical nanocrystal is decreased in case of existence of δ-potential, which leads to increase in the threshold frequency of the optical spectrum of absorption.  相似文献   

17.
A method of optically recording and reconstructing electrical signals in the form of one-dimensional holograms is described. For this purpose a pulsed laser beam is modulated according to the information to be stored. This beam is superimposed on a spatially and temporally constant reference beam, and the resulting interference pattern is recorded on a film which is moved past the light distribution. The one-dimensional holograms thus recorded appear arranged in narrow tracks which partially overlap.For reconstruction the film is driven past a spatially and temporally constant reconstructing wave. The illuminated holograms reconstruct a closely spaced chain of points which successively pass by a detector in which they produce an alternating current which, after appropriate amplification and filtering, presents the original signal.  相似文献   

18.
An experimental study is reported about the quenching of electronic excitation of Cs atoms caused by their collisions with a glass surface. The energy with which they are scattered from the surface after quenching has been measured to be 0.5 eV, which is about one-third of the excitation energy. A discussion is given of the mechanisms by which the excitation energy is partitioned between the atom and the surface in two different cases, namely, in the excitation of the atom adsorbed on the surface and in the collision of the preexcited atom with the surface.  相似文献   

19.
Cavitation within a pump causes structural vibration with noise, among other by-products. Experiments have shown that there is a discrete frequency or broadband peak within the audible noise spectra, which is in strong correlation with the development of the cavitation process in the pump. Furthermore, the peak of the discrete frequency, or broadband peak, coincides with the net positive suction head (NPSH) critical value, which corresponds to a 3% drop in the total delivery head. Therefore, the discrete frequency tone can be used to detect the incipience of cavitation and its development as well as to determine the NPSH required or critical value with in situ operation of a pump. In this study, we wanted to clarify the mechanism of noise generation, which is responsible for the discrete frequency component and on which cavitation has an important effect. For this purpose, three different measurement methods were used: the first is based on measurement of the sound pressure level (SPL) in the surrounding air, the second is based on measurement of the underwater acoustics and the third is based on measurement of the structural vibration. Experiments have shown that the characteristic discrete frequency tone, which is in close correlation with the cavitation process, is a result of structural vibrations (modes) or resonances caused by implosion of bubbles and bombardment of the inner surfaces of the pump.  相似文献   

20.
臧华平  曹磊峰  王传珂  蒋刚  魏来  范伟  周维民  谷渝秋 《物理学报》2011,60(3):34215-034215
新近提出的光学色散元件"之"字形光栅具有优越的衍射特征,在光谱测量和分析中具有重要的应用价值.本文基于卷积定理,采用一种新的数值计算方法对应用于X射线波段的"之"字形光栅的衍射模式进行了模拟计算,并将其衍射模式与传统光栅以及正弦光栅的衍射模式进行了比对研究,结果表明:"之"字形光栅可以将高级衍射抑制到低于一级衍射四个量级的水平,具有比传统光栅优越得多的衍射模式,与理论预期结果一致.在此基础上,又分析了实际应用过程中吸收体对X射线的吸收情况给"之"字形光栅衍射模式带来的影响,最终证实了"之"字形光栅具有较强 关键词: 之字形光栅 卷积定理 衍射模式 光谱测量  相似文献   

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