帮忙翻译一下啊? This equation also reproduces the temporal and spatial dependence of d computed numerically for a number of different time-independent velocity profiles.Clearly the fact that this equation gives good results in these cases does not impart any general validity,or guaranty it will work in any other cases.However since it allows,by construction,to find all limiting cases of interest,and since intermediate cases are also reproduced,we argue that it provides an accurate and efficient mean to estimate the size of the boundary layer in any intermediate case. This differential equation is intended primarily to be used in computational fluid dynamics calculations, where it can provide an effcient mean to estimate the mass transfer coefficient at a liquid/liquid or liquid/gas interface from knowledge of the local velocity profile in adjacent cells.It can also be used to construct new correlations Sh=f(Re,Sc)for different physical cases where the flow profile is known.Eq.(30)presents a typical example for such a correlation. We have limited this study to the mass transfer coefficient next to a planar interface.However this equation should be applicable for other surface geometries,by reinterpreting x and z as local coordinates in the plane of the interface and perpendicular to the interface.It might be also possible to determine a similar equation for the heat transfer coefficient.However our equation has been written for simple flow situations,and makes therefore implicitly use of the fact that the size of diffusion boundary layer is much smaller than the hydrodynamic boundary layer for most liquids,that is,Sc >>1.We would advise caution whenever the sizes of the boundary layers are not so disparate. 查看更多3个回答 . 2人已关注