为了研究波浪壁面对渠道中湍流流动阻力的影响规律,将任意形状的波浪壁面表达为一阶傅里叶模式,选取流动方向单位长度渠道作为研究对象,对该模型进行单位化处理,推导了渠道减阻系数的计算方法,通过与 DNS 计算结果对比,验证了本文计算...为了研究波浪壁面对渠道中湍流流动阻力的影响规律,将任意形状的波浪壁面表达为一阶傅里叶模式,选取流动方向单位长度渠道作为研究对象,对该模型进行单位化处理,推导了渠道减阻系数的计算方法,通过与 DNS 计算结果对比,验证了本文计算方法具有较好的准确性。通过 Fluent 流场分析软件计算得到不同的波数和幅值模型的压降损失,获得减阻系数随波数和幅值变化规律。选取不同的几何形状进行计算,并与一阶傅里叶模式下的结果进行对比,除具有内尖角壁面模型外,一阶傅里叶模式均可以进行较好的近似。该规律为建立减阻几何形状提供了一定参考。展开更多
The mode characteristics for twin coupled microdisks are investigated by finite-difference time-domain technique. In the coupled microdisks,the same order whispering-gallery(WG) modes can form coupled modes with split...The mode characteristics for twin coupled microdisks are investigated by finite-difference time-domain technique. In the coupled microdisks,the same order whispering-gallery(WG) modes can form coupled modes with split mode wavelengths. We find that the coupled fundamental and first order WG modes can have anticrossing mode coupling as their wavelengths approach the same value in some case,which prevents the cross of the coupled mode wavelengths. The anticrossing mode coupling greatly reduces the coupled mode Q-factor,because the coupled mode field distribution transfers between the fundamental and the first order WG modes.展开更多
The objective of this paper is to discuss the issue of the projection uniformity of asymmetric fractional factorials.On the basis of Lee discrepancy,the authors define the projection Lee discrepancy to measure the uni...The objective of this paper is to discuss the issue of the projection uniformity of asymmetric fractional factorials.On the basis of Lee discrepancy,the authors define the projection Lee discrepancy to measure the uniformity for low-dimensional projection designs.Moreover,the concepts of uniformity pattern and minimum projection uniformity criterion are proposed,which can be used to assess and compare two and three mixed levels factorials.Statistical justification of uniformity pattern is also investigated.展开更多
文摘为了研究波浪壁面对渠道中湍流流动阻力的影响规律,将任意形状的波浪壁面表达为一阶傅里叶模式,选取流动方向单位长度渠道作为研究对象,对该模型进行单位化处理,推导了渠道减阻系数的计算方法,通过与 DNS 计算结果对比,验证了本文计算方法具有较好的准确性。通过 Fluent 流场分析软件计算得到不同的波数和幅值模型的压降损失,获得减阻系数随波数和幅值变化规律。选取不同的几何形状进行计算,并与一阶傅里叶模式下的结果进行对比,除具有内尖角壁面模型外,一阶傅里叶模式均可以进行较好的近似。该规律为建立减阻几何形状提供了一定参考。
文摘The mode characteristics for twin coupled microdisks are investigated by finite-difference time-domain technique. In the coupled microdisks,the same order whispering-gallery(WG) modes can form coupled modes with split mode wavelengths. We find that the coupled fundamental and first order WG modes can have anticrossing mode coupling as their wavelengths approach the same value in some case,which prevents the cross of the coupled mode wavelengths. The anticrossing mode coupling greatly reduces the coupled mode Q-factor,because the coupled mode field distribution transfers between the fundamental and the first order WG modes.
基金supported by the National Natural Science Foundations of China under Grant Nos.11271147 and 11401596
文摘The objective of this paper is to discuss the issue of the projection uniformity of asymmetric fractional factorials.On the basis of Lee discrepancy,the authors define the projection Lee discrepancy to measure the uniformity for low-dimensional projection designs.Moreover,the concepts of uniformity pattern and minimum projection uniformity criterion are proposed,which can be used to assess and compare two and three mixed levels factorials.Statistical justification of uniformity pattern is also investigated.