圆管中管壁摩擦引起的湍流Turbulent Flow Caused By the Wall Friction in Circular Pipes

论文和Essay改写降重和AI查重工具！立刻免费获取！获取免费激活联系微信:idavidxiong

总览评价肖建华 * （河南理工大学

）摘要： For the fluid flow in pipes, when the friction of pipe wall is big enough the velocity near the wall will significantly smaller than the flow velocity in the pipe center

This will cause the material volume elements of fluid rotate along the tangent direction of circular pipe wall

The intrinsic rotation angle of such a local rotation is a function of radium from the pipe center where the viscosity parameter of fluid plays an essential role

This local intrinsic rotation not only produces an additional pressure field, but also produces turbulence when the transportation distance is big enough

This result is gained based on the Chen’s S+R decomposition of deformation gradient theorem

For the fluid flow problem, the related motion equations established on Chen’s rational mechanics theory is used in this paper

The theoretic equations are compared with traditional fluid motion equations

Traditional fluid motion equations (Navier-Stokes equation) are correct for non-symmetric stress fields, but they do not supply reasonable equations for the asymmetric stress fields

This is the essential disadvantage for the tradition fluid dynamics theory to predict the local rotation and the possibility of turbulent flow in the simple case of pipe flow problem

This research shows that the new theoretic formulation may be valuable to explain complex flow phenomena

关键词： turbulence, local rotation, asymmetric stress, motion equation, velocity gradient decomposition Xiao Jianhua * （ Henan Polytechnic University

） Abstract： For the fluid flow in pipes, when the friction of pipe wall is big enough the velocity near the wall will significantly smaller than the flow velocity in the pipe center