We investigate the role of extended intrinsic mean spin tensor introduced in this work for turbulence modelling in a non-inertial frame of reference. It is described by the Euclidean group of transformations and, in p...We investigate the role of extended intrinsic mean spin tensor introduced in this work for turbulence modelling in a non-inertial frame of reference. It is described by the Euclidean group of transformations and, in particular, its significance and importance in the approach of the algebraic Reynolds stress modelling, such as in a nonlinear K-ε model. To this end and for illustration of the effect of extended intrinsic spin tensor on turbulence modelling, we examine several recently developed nonlinear K-ε models and compare their performance in predicting the homogeneous turbulent shear flow in a rotating frame of reference with LES data. Our results and analysis indicate that, only if the deficiencies of these models and the like be well understood and properly corrected, may in the near future, more sophisticated nonlinear K-ε models be developed to better predict complex turbulent flows in a non-inertial frame of reference.展开更多
非惯性系下湍流的计算,对湍流模型的应用一直是一项挑战性的工作.作者提出"扩展内禀平均旋转张量"的概念,并且指出将在惯性系下发展的雷诺应力模型应用于非惯性系下的湍流模拟,非线性湍流模型中的平均旋转张量应该用"扩...非惯性系下湍流的计算,对湍流模型的应用一直是一项挑战性的工作.作者提出"扩展内禀平均旋转张量"的概念,并且指出将在惯性系下发展的雷诺应力模型应用于非惯性系下的湍流模拟,非线性湍流模型中的平均旋转张量应该用"扩展内禀平均旋转张量"替代,从而正确地反映非惯性系诱导的旋转效应.为了验证这一处理方法,采用4个非线性κ-ε模型,对充分发展的旋转槽道流进行了数值模拟.在较广泛的雷诺数和Rossby数范围进行的数值模拟表明,应用该技术途径,非线性κ-ε湍流模型CLS(Craft,Launder and Suga)模型和HM(Huang and Ma)模型可以相当好地捕捉旋转效应及其对湍流结构的影响,因此,可以令人满意地应用于工程湍流的计算.展开更多
文摘We investigate the role of extended intrinsic mean spin tensor introduced in this work for turbulence modelling in a non-inertial frame of reference. It is described by the Euclidean group of transformations and, in particular, its significance and importance in the approach of the algebraic Reynolds stress modelling, such as in a nonlinear K-ε model. To this end and for illustration of the effect of extended intrinsic spin tensor on turbulence modelling, we examine several recently developed nonlinear K-ε models and compare their performance in predicting the homogeneous turbulent shear flow in a rotating frame of reference with LES data. Our results and analysis indicate that, only if the deficiencies of these models and the like be well understood and properly corrected, may in the near future, more sophisticated nonlinear K-ε models be developed to better predict complex turbulent flows in a non-inertial frame of reference.
文摘非惯性系下湍流的计算,对湍流模型的应用一直是一项挑战性的工作.作者提出"扩展内禀平均旋转张量"的概念,并且指出将在惯性系下发展的雷诺应力模型应用于非惯性系下的湍流模拟,非线性湍流模型中的平均旋转张量应该用"扩展内禀平均旋转张量"替代,从而正确地反映非惯性系诱导的旋转效应.为了验证这一处理方法,采用4个非线性κ-ε模型,对充分发展的旋转槽道流进行了数值模拟.在较广泛的雷诺数和Rossby数范围进行的数值模拟表明,应用该技术途径,非线性κ-ε湍流模型CLS(Craft,Launder and Suga)模型和HM(Huang and Ma)模型可以相当好地捕捉旋转效应及其对湍流结构的影响,因此,可以令人满意地应用于工程湍流的计算.