کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
650870 1457323 2007 25 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Three-dimensional instabilities of laminar flow in a rough channel and the concept of hydraulically smooth wall
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Three-dimensional instabilities of laminar flow in a rough channel and the concept of hydraulically smooth wall
چکیده انگلیسی
Flow in a channel with distributed surface roughness is considered. Results of the linear stability analysis show that the presence of the roughness destabilizes the traveling-wave instability as well as introduces a new instability that manifests itself in the form of streamwise vortices. The critical conditions for the occurrence of both instabilities are given for different classes of roughness shape. It is shown that these conditions can be predicted with a reasonable accuracy in the case of an arbitrary (but Fourier transformable) roughness by considering only the leading Fourier mode (wavy-wall model). It is argued that the onset of instabilities provides a decision mechanism that determines whether a particular rough wall can be viewed as being hydraulically smooth in the case of transitional flows.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Journal of Mechanics - B/Fluids - Volume 26, Issue 3, May–June 2007, Pages 305-329
نویسندگان
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