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1.
新导出一个用旋转粘度计测量粘滞系数的公式, 并与文献上其它公式进行了比较.  相似文献   

2.
从理论上推导了在液面下的小球何时达到收尾速度公式,并给出一组实验数据,得出小球从液面自由下落时很快能达到收尾速度的结论。  相似文献   

3.
多管粘滞系数测量仪的改进   总被引:1,自引:1,他引:0  
王雪冬  刘平 《大学物理》1997,16(4):30-30,21
分析了单管,多管粘滞系数测量仪的优缺点,对测量仪进行了改进,使之测量更合理,更准确。  相似文献   

4.
落球法液体粘滞系数测定仪的改进   总被引:4,自引:1,他引:3  
通过对落球法液体粘滞系数测定仪的改进,消除了传统仪器的诸多弊端,保证了金属小球沿容器中心准确下落,计时准确性也明显提高,从而使测量误差大大降低。  相似文献   

5.
用气轨测g时,若忽略空气粘滞阻力对滑块的作用时,测出的g值与当地标准值有2%~4%的偏差。可采用"附加速度损失法","平均阻力法","消去法","积分法"等,可有效减小系统误差,提高测量准确度。  相似文献   

6.
利用改进的旋筒和光纤传感器精确测量了液体粘滞系数,使旋筒法实验产生了由定性到定量的转变。  相似文献   

7.
本文导出了小球在液体中下落的运动方程,并从理论上指出了测量粘滞系数实验中应怎样选取小球和液体以提高η的测量精度.  相似文献   

8.
本文介绍定温下,液体蓖麻油粘滞系数测量结果不确定度的评定,并着重讨论了由温度影响所引起的不确定度。  相似文献   

9.
田巨平  姚凯伦 《物理》1996,25(3):168-171
介绍了沉积岩的分形性质,简述了沉积岩中的分形在石油勘探和开发中的应用.  相似文献   

10.
对落球法测液体粘度的研讨   总被引:2,自引:0,他引:2  
本文通过理论计算,证明了用落球法测液体粘度时,小球落入液体实验效果最佳的速度。并给出了具体操作方法。  相似文献   

11.
The behaviors of aerosols having particle diameters of 1–5 μm were studied experimentally and the results were compared with numerical calculations. For the experimental study, a specially designed coagulation cylinder was developed and the moment method was used in the numerical predictions. The experimental results were characterized by the size parameters including the geometric mean diameter (GMD), the geometric standard deviation (GSD) and the particle number concentration (N). Particle distributions in the cylinder were measured at certain time intervals. In a closed cylinder, the mechanism governing aerosol behavior appeared to be gravitational coagulation. Separately, the numerical calculations were carried out using the moment method. The experimental results and the numerical predictions were in reasonable agreement. It is believed that the present work represents the first experimental study on gravitational coagulation.  相似文献   

12.
Neyens  Gerda 《Hyperfine Interactions》2001,136(3-8):171-177
New achievements in nuclear moment measurements on nuclei produced and spin-oriented in intermediate energy (50–80 MeV/u) projectile fragmentation reactions are presented. By combining different types of spin-orientation with different experimental techniques, we show that the magnetic dipole moments and electric quadrupole moments of exotic neutron rich nuclei in their ground state as well as in their excited isomeric states can be measured. A selection of recent experiments performed at the LISE spectrometer at GANIL (Caen, France) is described. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   

13.
This paper verifies the feasibility of the relative entropy method in selecting the most suitable statistical distribution for the experimental data, which do not follow an exponential distribution. The efficiency of the relative entropy method is tested through the fractional order moment and the logarithmic moment in terms of the experimental data of carbon fiber/epoxy composites with different stress amplitudes. For better usage of the relative entropy method, the efficient range of its application is also studied. The application results show that the relative entropy method is not very fit for choosing the proper distribution for non-exponential random data when the heavy tail trait of the experimental data is emphasized. It is not consistent with the Kolmogorov–Smirnov test but is consistent with the residual sum of squares in the least squares method whenever it is calculated by the fractional moment or the logarithmic moment. Under different stress amplitudes, the relative entropy method has different performances.  相似文献   

14.
After a brief review of the muon g-2 status,we discuss hypothetical errors in the Standard Model prediction that might explain the present discrepancy with the experimental value.None of them seems likely.In particular,a hypothetical increase of the hadroproduction cross section in low-energy e+e-collisions could bridge the muon g-2 discrepancy,but it is shown to be unlikely in view of current experimental error estimates.If,nonetheless,this turns out to be the explanation of the discrepancy,then the 95% CL upper bound on the Higgs boson mass is reduced to about 135 GeV which,in conjunction with the experimental 114.4 GeV 95%CL lower bound,leaves a narrow window for the mass of this fundamental particle.  相似文献   

15.
多级风扇/压气机三维粘性流场的数值分析   总被引:6,自引:1,他引:5  
采用叶排间掺混面模型,研究了多级跨音速风扇及压气机三维粘性流动数值模拟问题,利用LU-SGS隐式算法使计算过程快速收敛,通过高分辨率格式改善跨音速流场中激波的分辨率。对某双级跨音速风扇及五级压气机流场进行了计算,双级风扇各状态的计算结果与实验数据吻合较好。  相似文献   

16.
在铷泡光磁双共振实验中,当微波场很强时,光检测到在原来的七条共振峰间,有新的蜂出现,在场引起新电四极矩假设下,理论计算与实验结果相符  相似文献   

17.
生物力学中片流的边界元分析   总被引:1,自引:0,他引:1  
用边界元方法[1,2]研究了生物力学中肺毛细血管血液的流动,并对肺毛细血管的SFH模型,SFC模型进行了数值模拟,给出血液流动的速度场及血管壁上的面力分布和压力分布.对肺毛细管内皮细胞受的切应力,数值计算表明,正常情况下,在0~4.64×10-5N/cm2之间,这与Dewey实验结果[8](0~5×10-5N/cm2)相一致,肺胞的形态将按使呼吸膜受切应力值最小为原则构形.同时,本文方法还可为数值分析心血管内的血液流动提供一种有效的数值方法,这对生物力学和医学工程是有价值的.  相似文献   

18.
Using the quark-like model, we have improved the existing deviation between theoretical and experimental values of magnetic dipole moment of deuteron. Based upon Pauli Exclusion Principle, the constituent quarks form a ground state for l = 0. The expectation value of the deuteron magnetic dipole moment operator is determined to be equal to 0.861 597 8μ N in better agreement with the measured value of 0.857 437 6μ N as compared to the shell model calculations.  相似文献   

19.
水中上浮气泡动态特性研究   总被引:5,自引:0,他引:5       下载免费PDF全文
李帅  孙龙泉  张阿漫 《物理学报》2014,63(18):184701-184701
针对水中的上浮气泡,计入表面张力的作用,然后将气泡边界层内黏性效应分为法向和切向两部分,其中附加法向黏性应力通过Young-Laplace关系考虑;附加切向黏性力是基于黏性耗散能量等效原理,引入黏性修正压力代替.首先建立了轴对称和三维上浮气泡边界元模型,将数值结果与理论值和实验值进行对比分析,有良好的符合度,验证了数值模型的有效性;然后针对毫米量级上浮气泡的平衡速度与形态,讨论了气泡初始条件、表面张力和黏性对气泡上浮过程中动力学行为的影响;最后,提出了一种处理三维上浮气泡融合的数值方法,计算结果与实验现象符合良好,并且能够反映气泡融合后的复杂现象细节.  相似文献   

20.
采用三维粘性流场求解软件Fine/TURBO[1]对低压蒸汽透平下游排汽缸内的复杂流动进行数值模拟。计算中使用了Jameson的Runge-Kutta中心差分格式[2]和Baldwin-Lomax的代数湍流模型、计算结果同部分实验结果进行了对比,表明数值模拟揭示了排汽缸内复杂的旋涡结构,以及影响排气缸内压力恢复和总压损失的主要因素。  相似文献   

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