This paper reports the outcome of applying two di erent low-Reynolds-number eddy-viscosity models to resolve the complex three-dimensional motion that arises in turbulent ows in ducts with 90◦ bends. For the modelling of turbulence, the Launder and Sharma low-Re k– model and a recently produced variant of the cubic non-linear low-Re k– model have been employed. In this paper, developing turbule...

Güneş destekli hava ısıtıcıların çok yaygın kullanım ile birlikte ısı transferi verimlerinin düşük olduğu bilinmektedir. Bu konuda çeşitli çalışmalar yürütülmektedir. Yapılan bu çalışmada yutucu plaka üzerine kare kesit yapay pürüzlülük oluşturularak tasarlanan bir güneş ısıtıcısının sayısal analizi yapılmıştır. Kütle, momentum ve enerji korunumu denklemlerinin simülasyonu, kullanılan hesaplama...

Analytical solutions are presented for laminar fully-developed flow in micro/minichannels of hyperelliptical and regular polygonal cross-sections. The considered geometries cover a wide range of common simply connected shapes including circle, ellipse, rectangle, rhomboid, star-shape, equilateral triangle, square, pentagon, and hexagon. Therefore, the present approach can be considered as a gen...

Particles suspended in fluid flow through a closed duct can focus to specific stable locations the cross-section due hydrodynamic forces arising from inertia of disturbed fluid. Such particle focusing is exploited biomedical and industrial technologies separate particles by size. In curved ducts, result balance between two dominant on particle: (i) inertial lift small fluid, (ii) drag cross-sec...

In order to achieve the best performance of a thermal system, two major analyses must be carried out on system: energy and entropy generation. The scenario is mechanism in which system has minimum generation highest Nu number. this regard, we investigated number fluid flow through tubes various cross-sections, namely circular tubes, square channels, rectangular ducts. Additionally, addition nan...