Irek Davletshin, Nikolay Dushin, Nikolay Mikheev, Radif Shakirov
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引用次数: 0
Abstract
Experiments were carried out to study hydrodynamics and heat transfer in a channel with discrete roughness elements on walls. Semicircle ribs with the height of 1.4 % of the hydraulic diameter of the channel were considered. Various rib geometries and positions were examined: solid ribs and ribs with slits, various streamwise and spanwise pitches, inline and staggered rib arrangements. Heat transfer enhancement and thermal-hydraulic performance were estimated. Integral and local values of the heat transfer coefficient were measured. Optical measurements yielded the fields of velocities and turbulent characteristics of the flow. Simultaneous analysis of hydrodynamic and thermal parameters of flow was carried out. Formation mechanisms of the kinematic structure of flow and heat transfer on roughened walls were considered. The distribution of heat transfer coefficient was shown to depend on the turbulent structure of flow, namely the vertical fluctuation of velocity in the near-wall region.
期刊介绍:
The International Journal of Thermal Sciences is a journal devoted to the publication of fundamental studies on the physics of transfer processes in general, with an emphasis on thermal aspects and also applied research on various processes, energy systems and the environment. Articles are published in English and French, and are subject to peer review.
The fundamental subjects considered within the scope of the journal are:
* Heat and relevant mass transfer at all scales (nano, micro and macro) and in all types of material (heterogeneous, composites, biological,...) and fluid flow
* Forced, natural or mixed convection in reactive or non-reactive media
* Single or multi–phase fluid flow with or without phase change
* Near–and far–field radiative heat transfer
* Combined modes of heat transfer in complex systems (for example, plasmas, biological, geological,...)
* Multiscale modelling
The applied research topics include:
* Heat exchangers, heat pipes, cooling processes
* Transport phenomena taking place in industrial processes (chemical, food and agricultural, metallurgical, space and aeronautical, automobile industries)
* Nano–and micro–technology for energy, space, biosystems and devices
* Heat transport analysis in advanced systems
* Impact of energy–related processes on environment, and emerging energy systems
The study of thermophysical properties of materials and fluids, thermal measurement techniques, inverse methods, and the developments of experimental methods are within the scope of the International Journal of Thermal Sciences which also covers the modelling, and numerical methods applied to thermal transfer.