Fin Shape Thermal Optimization Using Bejan's Constructal Theory
Fin Shape Thermal Optimization Using Bejan's Constructal Theory

Author: Giulio Lorenzini

Publisher: Morgan & Claypool Publishers

Published: 2011-04-29

Total Pages: 222

ISBN-13: 1608456072

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The book contains research results obtained by applying Bejan's Constructal Theory to the study and therefore the optimization of fins, focusing on T-shaped and Y-shaped ones. Heat transfer from finned surfaces is an example of combined heat transfer natural or forced convection on the external parts of the fin, and conducting along the fin. Fin's heat exchange is rather complex, because of variation of both temperature along the fin and convective heat transfer coefficient. Furthermore possible presence of more fins invested by the same fluid flow has to be considered. Classical fin theory tried to reduce the coupled heat transfer problem to a one-dimensional problem by defining an average temperature of the fin and writing equations using this parameter. However, it was shown that this approach cannot be used because of the effects of two-dimensional heat transfer, especially in the presence of short fins. CFD codes offer the possibility to consider bi-dimensional (and more generally, three-dimensional) effects and then a more real approach to the physic phenomena of finned surface's heat exchange. A commercial CFD code was used to analyse the case of heat exchange in presence of T-shaped fins, following an approach suggested by Bejan's Constructal Theory. The comparative results showed a significant agreement with previous research taken as a reference, and this result allows for the application of this approach to a wider range of systems. T-shaped optimized fin geometry is the starting point for further research. Starting from the optimal results (T-shape optimized fins), we show the trend of the assessment parameter (the dimensionless conductance) in function of the angle α between the two horizontal arms of the fin. A value for α, 90°

Fin-Shape Thermal Optimization Using Bejan's Constuctal Theory
Fin-Shape Thermal Optimization Using Bejan's Constuctal Theory

Author: Giulio Lorenzini

Publisher: Springer Nature

Published: 2022-05-31

Total Pages: 205

ISBN-13: 3031793331

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The book contains research results obtained by applying Bejan's Constructal Theory to the study and therefore the optimization of fins, focusing on T-shaped and Y-shaped ones. Heat transfer from finned surfaces is an example of combined heat transfer natural or forced convection on the external parts of the fin, and conducting along the fin. Fin's heat exchange is rather complex, because of variation of both temperature along the fin and convective heat transfer coefficient. Furthermore possible presence of more fins invested by the same fluid flow has to be considered. Classical fin theory tried to reduce the coupled heat transfer problem to a one-dimensional problem by defining an average temperature of the fin and writing equations using this parameter. However, it was shown that this approach cannot be used because of the effects of two-dimensional heat transfer, especially in the presence of short fins. CFD codes offer the possibility to consider bi-dimensional (and more generally, three-dimensional) effects and then a more real approach to the physic phenomena of finned surface's heat exchange. A commercial CFD code was used to analyse the case of heat exchange in presence of T-shaped fins, following an approach suggested by Bejan's Constructal Theory. The comparative results showed a significant agreement with previous research taken as a reference, and this result allows for the application of this approach to a wider range of systems. T-shaped optimized fin geometry is the starting point for further research. Starting from the optimal results (T-shape optimized fins), we show the trend of the assessment parameter (the dimensionless conductance) in function of the angle a between the two horizontal arms of the fin. A value for a, 90°

Systems Engineering
Systems Engineering

Author: Giulio Lorenzini

Publisher:

Published: 2011

Total Pages: 0

ISBN-13: 9788303179333

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The book contains research results obtained by applying Bejan's Constructal Theory to the study and therefore the optimization of fins, focusing on T-shaped and Y-shaped ones. Heat transfer from finned surfaces is an example of combined heat transfer natural or forced convection on the external parts of the fin, and conducting along the fin. Fin's heat exchange is rather complex, because of variation of both temperature along the fin and convective heat transfer coefficient. Furthermore possible presence of more fins invested by the same fluid flow has to be considered. Classical fin theory tried to reduce the coupled heat transfer problem to a one-dimensional problem by defining an average temperature of the fin and writing equations using this parameter. However, it was shown that this approach cannot be used because of the effects of two-dimensional heat transfer, especially in the presence of short fins. CFD codes offer the possibility to consider bi-dimensional (and more generally, three-dimensional) effects and then a more real approach to the physic phenomena of finned surface's heat exchange. A commercial CFD code was used to analyse the case of heat exchange in presence of T-shaped fins, following an approach suggested by Bejan's Constructal Theory. The comparative results showed a significant agreement with previous research taken as a reference, and this result allows for the application of this approach to a wider range of systems. T-shaped optimized fin geometry is the starting point for further research. Starting from the optimal results (T-shape optimized fins), we show the trend of the assessment parameter (the dimensionless conductance) in function of the angle a between the two horizontal arms of the fin. A value for a, 90°

Simplified Models for Assessing Heat and Mass Transfer
Simplified Models for Assessing Heat and Mass Transfer

Author: Giulio Lorenzini

Publisher: Springer Nature

Published: 2022-06-01

Total Pages: 106

ISBN-13: 3031793609

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The aim of this book is to supply valid and reasonable parameters in order to guide the choice of the right model of industrial evaporative tower according to operating conditions which vary depending on the particular industrial context: power plants, chemical plants, food processing plants and other industrial facilities are characterized by specific assets and requirements that have to be satisfied. Evaporative cooling is increasingly employed each time a significant water flow at a temperature which does not greatly differ from ambient temperature is needed for removing a remarkable heat load; its aim is to refrigerate a water flow through the partial evaporation of the same.

Tree-Shaped Fluid Flow and Heat Transfer
Tree-Shaped Fluid Flow and Heat Transfer

Author: António F. Miguel

Publisher: Springer

Published: 2018-04-20

Total Pages: 108

ISBN-13: 3319732609

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This book provides the first comprehensive state-of-the-art research on tree (dendritic) fluid flow and heat transfer. It covers theory, numerical simulations and applications. It can serve as extra reading for graduate-level courses in engineering and biotechnology. Tree flow networks, also known as dendritic flow networks, are ubiquitous in nature and engineering applications. Tree-shaped design is prevalent when the tendency of the flow (fluid, energy, matter and information) is to move more easily between a volume (or area) and a point, and vice versa. From the geophysical trees to animals and plants, we can observe numerous systems that exhibit tree architectures: river basins and deltas, lungs, circulatory systems, kidneys, vascularized tissues, roots, stems, and leaves, among others. Tree design is also prevalent in man-made flow systems, both in macro- and microfluidic devices. A vast array of tree-shaped design is available and still emerging in chemical engineering, electronics cooling, bioengineering, chemical and bioreactors, lab-on-a-chip systems, and smart materials with volumetric functionalities, such as self-healing and self-cooling. This book also addresses the basic design patterns and solutions for cooling bodies where there is heat generation. Several shapes of fin as well as assemblies of fins are addressed. An up-to-date review of cavities, i.e., inverted or negative fins, for facilitating the flow of heat is also presented. Heat trees using high thermal conductivity material can be used in the cooling of heat-generating bodies, and can also be applied to the cooling of electronics.

Shape and Structure, from Engineering to Nature
Shape and Structure, from Engineering to Nature

Author: Adrian Bejan

Publisher: Cambridge University Press

Published: 2000-10-16

Total Pages: 370

ISBN-13: 9780521793889

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Seemingly universal geometric forms unite the flow systems of engineering and nature. For example, tree-shaped flows can be seen in computers, lungs, dendritic crystals, urban street patterns, and communication links. In this groundbreaking book, Adrian Bejan considers the design and optimization of engineered systems and discovers a deterministic principle of the generation of geometric form in natural systems. Shape and structure spring from the struggle for better performance in both engineering and nature. This idea is the basis of the new constructal theory: the objective and constraints principle used in engineering is the same mechanism from which the geometry in natural flow systems emerges. From heat exchangers to river channels, the book draws many parallels between the engineered and the natural world. Among the topics covered are mechanical structure, thermal structure, heat trees, ducts and rivers, turbulent structure, and structure in transportation and economics. The numerous illustrations, examples, and homework problems in every chapter make this an ideal text for engineering design courses. Its provocative ideas will also appeal to a broad range of readers in engineering, natural sciences, economics, and business.

Advances in Heat Transfer
Advances in Heat Transfer

Author: Ephraim M. Sparrow

Publisher: Academic Press

Published: 2013-11-19

Total Pages: 360

ISBN-13: 0124079326

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Advances in Heat Transfer fills the information gap between regularly scheduled journals and university-level textbooks by providing in-depth review articles over a broader scope than in journals or texts. The articles, which serve as a broad review for experts in the field, will also be of great interest to non-specialists who need to keep up-to-date with the results of the latest research. This serial is essential reading for all mechanical, chemical and industrial engineers working in the field of heat transfer, graduate schools or industry. This serial is essential reading for all mechanical, chemical and industrial engineers working in the field of heat transfer, graduate schools or industry

Case Studies in Forensic Physics
Case Studies in Forensic Physics

Author: Gregory A. DiLisi

Publisher: Springer Nature

Published: 2022-06-01

Total Pages: 146

ISBN-13: 3031020863

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This book focuses on a forensics-style re-examination of several historical events. The purpose of these studies is to afford readers the opportunity to apply basic principles of physics to unsolved mysteries and controversial events in order to settle the historical debate. We identify nine advantages of using case studies as a pedagogical approach to understanding forensic physics. Each of these nine advantages is the focus of a chapter of this book. Within each chapter, we show how a cascade of unlikely events resulted in an unpredictable catastrophe and use introductory-level physics to analyze the outcome. Armed with the tools of a good forensic physicist, the reader will realize that the historical record is far from being a set of agreed upon immutable facts; instead, it is a living, changing thing that is open to re-visitation, re-examination, and re-interpretation.

Empowering Professional Teaching in Engineering
Empowering Professional Teaching in Engineering

Author: John Heywood

Publisher: Springer Nature

Published: 2022-05-31

Total Pages: 223

ISBN-13: 303179382X

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Each one of us has views about education, how discipline should function, how individuals learn, how they should be motivated, what intelligence is, and the structures (content and subjects) of the curriculum. Perhaps the most important beliefs that (beginning) teachers bring with them are their notions about what constitutes "good teaching". The scholarship of teaching requires that (beginning) teachers should examine (evaluate) these views in the light of knowledge currently available about the curriculum and instruction, and decide their future actions on the basis of that analysis. Such evaluations are best undertaken when classrooms are treated as laboratories of inquiry (research) where teachers establish what works best for them. Two instructor centred and two learner centred philosophies of knowledge, curriculum and instruction are used to discern the fundamental (basic) questions that engineering educators should answer in respect of their own beliefs and practice. They point to a series of classroom activities that will enable them to challenge their own beliefs, and at the same time affirm, develop, or change their philosophies of knowledge, curriculum and instruction.