کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
799348 903452 2009 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Global instabilities in inhomogeneous mixed convection flows in semi-infinite porous media
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی مکانیک
پیش نمایش صفحه اول مقاله
Global instabilities in inhomogeneous mixed convection flows in semi-infinite porous media
چکیده انگلیسی
We study the nonlinear dynamic of mixed convection in semi-infinite porous media heated non-uniformly from below and through which an axial flow is maintained. Because the imposed inhomogeneous temperature profile varies slowly downstream, the WKBJ expansion is used specifically to determine the local absolute instability. Direct numerical simulations are carried out in the case when the inhomogeneity promotes sufficiently extended absolute instability at the inlet. It is found that the frequencies in the oscillating region are identical to the absolute frequencies at the inlet. Moreover, the distance separating the inlet to the spatial position where the trailing front of the globally unstable waves saturated is found to obey to a well defined scaling law.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Mechanics Research Communications - Volume 36, Issue 2, March 2009, Pages 260-264
نویسندگان
, ,