Progress in the development of high performance thermal systems has stimulated interest in methods to improve heat transfer, popularly called “heat transfer augmentation”. It has become second generation heat transfer technology. New techniques are primarily employed in a variety of thermal apparatuses encountered in process and chemical industries, including oil refineries and gas production plants as well as in power generation plants (thermal, nuclear, solar, geothermal, ocean thermal, etc.).
This course describes the most important and practical issues related to the optimum selection of various types of augmentation techniques employed for heat exchangers working with single-phase fluids (heaters or coolers) or with phase change fluids (evaporators, reboilers, condensers, etc.) The course will briefly survey basics of fluid flow and heat transfer in thermal apparatuses and continue with a detailed explanation of the most efficient passive (extended surfaces, fins, swirl flow devices, etc.) and active techniques (surface and fluid vibration etc.) for single phase flow as well as for fluids with phase-change (two-phase flows). Performance evaluation criteria (PEC) related to these techniques, as well as technical and economical issues, such as manufacturing costs, problems in operation, maintenance issues and others will be covered.
Highlights of the course include:
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Basics of selecting the most appropriate heat augmentation technique for the given application: augmentation techniques improve heat transfer for the price of increased pumping power
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Guidance for performance evaluation criteria which are basis for selection
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Practical real-life examples where finned tubes and tube inserts require careful operation and maintenance
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Interplay of various influencing design parameters: two or more techniques can work together as compound augmentation
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Economical issues: cost and benefit analysis