半円管入口の層流境界層

概要

論文の詳細を見る
It is very difficult to find the entrance region of a conduit with semi-circular crosssection. The authors treated this problem and found the following approximate solution.Provided that the thickness of the boundary layer increased uniformly from theentire entrance section of a conduit, the velocity at the central portion was ca1culated.Regarding this velocity as that of main f1ow, the authors calculated the thickness ofthe boundary layers of the circular arching wall and of the f1at plate wall, on thesymmetric plane of the semi-circular pipe. The velocity at the central portion wascorrected so that the velocity at the position where these two boundary layers metmay be maximum. As the result of the repetition of such procedure, the positionwhere the boundary layers developed from both walls met was found to be agreedwith the position of the maximum velocity in the previous paper in the case of asteady flow. It was also found that the profile of the velocity distribution was quitesimilar to that of the exact solution.The calulated entrance distance wasx = 0.0337a^2Um/νThis value, however, does not mean that the entrance region finish completely atthis distance.
福井大学工学部の論文
1966-03-00