3.4.3Bowen’s general scale-up method
Bowen [1961], on the other hand, proposed that for turbulent flow of a particular
fluid (exhibiting time independent behaviour), the wall shear stress, w,
:could be expressed as
where A, b and c are constants for the fluid and may be determined from experimental
measurements in small diameter tubes. For laminar flow, wall shear
stress . w/ – apparent wall shear stress .8V=D/ data for different diameter
tubes, coincide. However, for turbulent conditions, as shown schematically
in Figure 3.9, diameter appears to be an additional independent parameter.
Because of the inclusion of a diameter effect explicitly, this method is to
be preferred for scaling up the results of small scale pipe experiments to
predict frictional pressure drops for the same fluid in large diameter pipes.
Note that this method does not offer a generalised scheme of calculating
pressure drop in contrast to the method of Metzner and Reed [1955] and
Dodge and Metzner [1959].
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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