Download or read book Experimental and Computational Heat Transfer Analysis of Micro Channel Heat Sink with Different Manifold Arrangements written by Independently Published and published by . This book was released on 2018-09-14 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat sink is an object, system or an environment that absorbs or dissipates heat from anotherusing direct or radiant thermal contact. Heat sink is object that enhances heat dissipation fromcomponent to a cooler ambient. The primary purpose of a heat sink is to maintain the temperatureof the device being cooled within acceptable limits as specified by the component manufacturer.Heat sinks are normally made up of copper or aluminum and is in directly contact with microchipson a circuit board.This advancement leads to the development of miniaturized systems, which further leads tovarious applications, as in the field of medical science, electronic and bioengineering. These typesof systems often contain small scale fluid channels embedded in the surrounding solids withheating sourcesStudy have been done on the different shapes of manifolds through the project. In this workdifferent watts (50, 75, 100 and 125 W) are used with Reynolds number ranging from 342 to857.Due to the instability of flow at the entrance and exit regions of the micro channels, it is thebasic needs to come up with an efficient design of inlet and outlet manifold shapes and with anefficient design of micro-channels.The overall performance of micro channel heat sink (MCHS) as a system is affected by the inletand outlet manifold arrangements in addition to array of micro channel. In the present study theexperimental analysis is performed w.r.t the heat transfer coefficient, pressure drop and Nusseltnumber for three different manifold arrangements. In the experiment deionized water is made toflow through the inlet manifolds to the array of micro channels and exit is through outletmanifolds. In the present work three different arrangements: Rectangular (R), Rectangle withsemi-circular (RSC) and Divergent Convergent (DC) of the inlet and outlet manifolds areselected. Within the Reynolds number range 342-857 DC type manifold has highest heat transfercoefficient of about 24%-32% in comparison to Rectangle (R) type manifold while Rectanglewith semi-circle (RSC) shows an enhancement of about 7% to 10% as compare to Rectangular(R).
Download or read book THERMAL and HYDRAULIC PERFORMANCE on MICRO CHANNELS MANIFOLD ARRANGEMENTS written by Independently Published and published by . This book was released on 2018-09-04 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat generated by the electronic devices must be dissipated to the environment for better performance, improving reliability and preventing failure. According to Moore's law of semiconductor the transistor density doubles roughly every 18 months causing higher heat load. So, the past couple of decades have witnessed a rapid progress in the applications of miniaturization forcing the size of the circuits with high demand on increased operating speeds and package densities. Heat sink is an object or system that absorbs or dissipates heat from another using direct or radiant thermal contact. It is seen that heat sink transfers thermal energy from a source at higher temperature to a fluid medium at a lower temperature. Heat sinks are used in integrated circuits and power handling semiconductors to reduce their temperature through increased thermal mass and heat dissipations. It can also be used in case of refrigeration, electronic cooling, high performance microprocessors, chemical process and power systems. Micro-channels and mini-channels based heat sinks are provided large surface to volume ratio. The greatest advantage of micro-channels heat sinks are high heat transfer rate obtained from a large surface to volume ratio. Micro scale heat transfer has received more interest due to decrease in the size of devices, such as in electronic equipment's because there is an increase in amount of heat to be dissipated per unit area. The performance of these devices is largely depends on their temperature. So, it is an important issue to keep the electronics at reasonable temperature levels. Micro-channels heat sinks are known as one of the effective cooling techniques. Various researchers have looked for finding the ways of cooling to improve the performance of system. They have investigate the liquid flow based MCHS for thermal management of electronics devices. The researchers have looked for efficient cooling technique, taking into account the cost, leakage and reliability of system. Microchannel heat sink has an inlet manifold, from where the liquid is supplied to the array of micro-channels and an outlet manifold, from where the liquid is collected after being passed through the micro-channels. These inlet and outlet manifolds are arranged in many different ways by number of researchers. As the different fluid flow arrangements have proposed, due to that reasons the different fluid flow arrangements are expected to affect the heat transfer and fluid flow characteristics within the micro-channels heat 5 sink. However, it is important to investigate the effects of inlet and outlet manifold arrangements for better micro-channels heat sink performance. The literature review indicates that research work available by many of researchers have focused on the heat transfer and fluid flow analysis within the micro-channels. However, no detailed experimental study has been carried in order out to get the effects of flow arrangements and shape inlet and outlet manifold arrangements on the performance of MCHS. In order to check the performance of the heat sink, it is necessary to investigate the effects of inlet and outlet manifold arrangements on heat transfer performance of micro-channels. In the present research work, micro-channels with three different tapered manifold arrangements were fabricated to study the effects of inlet and outlet manifold arrangements shapes on the performance of MCHSs. In this research work, shape and number of micro-channels were same in all three different test pieces, and the difference was only due to the shape of three different inlet and outlet manifold arrangements. The flow configuration was also same in all three cases. The experimental results were obtained with the help of five heat input values (50W, 75W, 100W, 125W and 150W), four Reynolds numbers (575.16, 690.19, 805.23 and 920.26), and the hydraulic diameter of micro-channel 833μm and taking total 60 experimental trial runs.
Download or read book Microscale and Nanoscale Heat Transfer written by C.B. Sobhan and published by CRC Press. This book was released on 2008-06-12 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: Through analyses, experimental results, and worked-out numerical examples, Microscale and Nanoscale Heat Transfer: Fundamentals and Engineering Applications explores the methods and observations of thermophysical phenomena in size-affected domains. Compiling the most relevant findings from the literature, along with results from their own re
Download or read book Two phase Flow and Heat Transfer written by David Butterworth and published by . This book was released on 1979 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Silicon Microchannel Heat Sinks written by Lian Zhang and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-phase microchannel cooling is one of the most promising thermal-management technologies for future high-power IC chips. Understanding the boiling process and the two-phase-flow behavior in microchannels is the key to successful implementation of a microchannel heat sink. This book focuses on the phase-change phenomena and the heat transfer in sub-150 nm diameter silicon microchannels, with emphasis on thermal measurement and modeling, and the impact of small dimensions on two-phase flow regimes.
Download or read book Heat Transfer and Fluid Flow Analysis of Spiral Microchannel Heat Sink written by Independently Published and published by . This book was released on 2018-09-14 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The microchannel are used to augment the heat transfer rate especially for the cooling in electronic components. Today's electronic components are required to perform tasks at a faster rate, and so high-powered integrated circuits have been produced in order to meet this need. These high-speed circuits are expected to generate heat fluxes that will cause the circuit to exceed its allowable temperature. In order to solve this problem, microchannel heat sink were introduced in 1981 by Tuckerman & Pease and have since been the study of many researchers in the field of fluid mechanics. The heat generated by the electronic component is transferred to the coolant by forced convention. The microchannel causes a decrease in the thickness of thermal boundary layer, which generates a decrease in the convective resistance to heat transfer, thus generating high cooling rates. To the best knowledge of the authors, not much work was done on Spiral type Microchannel Heat Sink. In the present work an aluminum piece of dimension 50mmx 50mm x 5mm with spiral microchannel is fabricated and heat transfer and fluid flow analysis will be performed. The liquid fluid is allowed to flow inside the grove and measurement is taken at the inlet and outlet of the plenum for pressure drop, temperature variation and heat transfer rate. In present work the research is studied both analytically and experimentally. In analytical work the computational study is carried out with the specific boundary conditions. In inner boundary condition the fluid is pass through the microchannel with the mass flow rate of 1lite per hour (LPH) and at outer boundary condition the environmental pressure of 101325Pa is provided. The heat source of 25Watt is given at the bottom surface of Spiral Microchannel. The wattage variation is as 25W, 35W, 45W, 55W, 65W keeping the flow rate constant i.e 1LPH. Similar wattage variation is performed at every flow rate 1.5LPH, 2LPH, 2.5LPH, 3LPH. This is done for two different cases, Case 1: Entry of fluid at Inner Spiral Eye (EISE) and for Case 2: Entry of fluid at Outer Spiral Eye (EOSE) in order to conclude which case gives the best result. This computational study of result is compared with the experimental result in order to verify the research. In this research the best result is obtained in Case 1 i.e EISE. It is due to the fact that the pressure drop obtain in Case 1 is less than the Case 2 which depicts that the rate of heat transfer is more in case of EISE.
Download or read book Fouling of Heat Exchangers written by T.R. Bott and published by Elsevier. This book was released on 1995-04-13 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique and comprehensive text considers all aspects of heat exchanger fouling from the basic science of how surfaces become fouled to very practical ways of mitigating the problem and from mathematical modelling of different fouling mechanisms to practical methods of heat exchanger cleaning. The problems that restrict the efficient operation of equipment are described and the costs, some of them hidden costs, that are associated with the fouling of heat exchangers are discussed. Some simple concepts and models of the fouling processes are presented as part of the introduction to the subject. Advice on the selection, design, installation and commissioning of heat exchangers to minimise fouling is given. A large part of the text is devoted to the use of chemical and other additives to reduce or eliminate the problem of fouling. Another large section is designed to give information on both on-line and off-line cleaning of heat exchangers. One of the difficulties faced by designers and operators of heat exchangers is anticipating the likely extent of fouling problems to be encountered with different flow streams. Another large section addresses the question and describes methods that have been used in attempting to define fouling potential. The book concludes with a chapter on how fouling information can be obtained using plant data, field tests and laboratory studies.
Download or read book Heat Transfer and Fluid Flow in Minichannels and Microchannels written by Satish Kandlikar and published by Elsevier. This book was released on 2006 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: &Quot;This book explores flow through passages with hydraulic diameters from about 1 [mu]m to 3 mm, covering the range of minichannels and microchannels. Design equations along with solved examples and practice problems are also included to serve the needs of practicing engineers and students in a graduate course."--BOOK JACKET.
Download or read book Thermal Transport in Oblique Finned Micro Minichannels written by Yan Fan and published by Springer. This book was released on 2014-10-15 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main aim of this book is to introduce and give an overview of a novel, easy, and highly effective heat transfer augmentation technique for single-phase micro/minichannel heat sink. The specific objectives of the volume are to: Introduce a novel planar oblique fin microchannel and cylindrical oblique fin minichannel heat sink design using passive heat transfer enhancement techniques Investigate the thermal transport in both planar and cylindrical oblique fin structures through numerical simulation and systematic experimental studies. Evaluate the feasibility of employing the proposed solution in cooling non-uniform heat fluxes and hotspot suppression Conduct the similarity analysis and parametric study to obtain empirical correlations to evaluate the total heat transfer rate of the oblique fin heat sink Investigate the flow mechanism and optimize the dimensions of cylindrical oblique fin heat sink Investigate the influence of edge effect on flow and temperature uniformity in these oblique fin channels.
Download or read book written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Study of Micro Pin fin Heat Sinks and Supercritical Carbon Dioxide Microchannel Heat Exchanger written by Cameron J. Naderi and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Microchannels in the application of heat sinks and heat exchangers play an important role in the field of heat transfer as the ever-increasing need for smaller components becomes apparent. Microchannels, although demanding larger pumping power in the systems they are integrated in, provide the superseding benefit of efficient heat transfer in a smaller and more cost-effective product when compared to larger scale heat exchange devices. This thesis focused on two areas relating to the study of microchannels. The first explored the performance of micro pin-fin heat sinks in quantitative studies of both the heat transfer and pressure drop of varying pin aspect and pitch ratios. Additionally, the study attempted to discover the effect of vortex shedding that occurs within the pin arrays of certain heat sinks and the geometric parameters that allow or prohibit its onset. The study found there to be a set of criteria for pin aspect and pitch ratios that would allow for vortex shedding, a flow feature that results in better heat transfer and lower pressure drop across the heat sink. The second topic examined in this thesis was the use of microchannels in a recuperator heat exchanger used in a supercritical carbon dioxide power generation cycle. A unit cell design of a heat exchanger was designed and tested for its heat transfer and pressure drop performance in order to provide results that would aid in designing a scaled-up version that would meet real-world demands. A viable design was created that could withstand conditions up to 90 ̊C and 120bar while also performing at 95% effectiveness.
Download or read book Advanced Computational Methods and Experiments in Heat Transfer X written by Bengt Sundén and published by WIT Press. This book was released on 2008-06-19 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: In engineering design and development, reliable and accurate computational methods are requested to replace or complement expensive and time consuming experimental trial and error work. Tremendous advancements have been achieved during recent years due to improved numerical solutions of non-linear partial differential equations and computer developments to achieve efficient and rapid calculations. Nevertheless, to further progress in computational methods will require developments in theoretical and predictive procedures – both basic and innovative – and in applied research. Accurate experimental investigations are needed to validate the numerical calculations. This book contains the edited versions of the papers presented at the Tenth International Conference on Advanced Computational Methods and Experimental Measurements in Heat Transfer and Mass Transfer held in Maribor, Slovenia in July 2008. The objective of this conference series is to provide a forum for presentation and discussion of advanced topics, new approaches and application of advanced computational methods and experimental measurements to heat and mass transfer problems. The contributed papers are grouped in the following appropriate sections to provide better access for readers: Natural and forced convection; Heat exchangers; Advances in computational methods; Heat recovery; Heat transfer; Modelling and experiments.
Download or read book Analytical Heat and Fluid Flow in Microchannels and Microsystems written by Renato M. Cotta and published by Springer. This book was released on 2015-10-10 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the modeling and analysis of heat and fluid flow in microchannels and micro-systems, compiling a number of analytical and hybrid numerical-analytical solutions for models that account for the relevant micro-scale effects, with the corresponding experimental analysis validation when applicable. The volume stands as the only available compilation of easy to use analytically-based solutions for micro-scale heat and fluid flow problems, that systematically incorporates the most relevant micro-scale effects into the mathematical models, followed by their physical interpretation on the micro-system behavior.
Download or read book On the Optimization of Performance in Fractal like Branching Microchannel Heat Transfer Devices written by Douglas Benjamin Heymann and published by . This book was released on 2011 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fractal-like branching microchannel flow networks have been found to improve wall temperature uniformity and decrease both pressure drop and flow power compared to arrays of straight microchannels. The present study seeks to maximize the benefits of fractal-like branching channels by means of a gradient-based optimization algorithm. The algorithm identifies the geometric parameters that yield the highest ratio of benefit to cost; the benefit being the heat transfer with cost being flow power. The stream-wise pressure and wall temperature distributions were determined numerically using one-dimensional models validated using experimental diagnostics and computational flow analyses. Pressure distributions were used to assess flow power, and wall temperature was used as an optimization constraint. Several geometric constraints were imposed during optimization to ensure sufficient bonding area for fabrication, to maximize convective surface area and to prevent channel overlap. Three fractal-like devices were studied and optimized: a single-phase heat sink, a two-phase heat sink and a single-phase oil-to-water heat exchanger. The flow rate of the three devices was constrained using a maximum wall temperature constraint for the single-phase heat sink, the critical heat flux for the two-phase heat sink, and a fixed cold side mass flow rate and temperature rise in the case of the heat exchanger. The optimized solutions were found to depend highly on both the geometric and flow constraints imposed. As the terminal channel width was reduced, flow power was reduced in both single-phase and two-phase heat sinks. However, the flow power was increased in the heat exchanger due to the constrained volumetric flow rate. In addition, results show that if a maximum wall temperature constraint is employed, single-phase flow outperforms two-phase flow in terms of reduction in flow power. However when constrained by a critical heat flux, two-phase networks outperform single-phase networks by up to 150%
Download or read book Phase Change Material Based Heat Sinks written by Srikanth Rangarajan and published by CRC Press. This book was released on 2019-11-20 with total page 223 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phase-change Material based heat sinks and associated optimization remains a topic of great interest, as evident from the increasing number of citations and new applications and miniaturization. Often the multi objective perspective of such heat sinks is ignored. This book introduces the readers to the PCM based heat sinks and Multi objective optimization. The authors have also included interesting in house experimental results on the "Rotating heat sinks" which is a first of a kind work. Useful to budding thermal researchers and practicing engineers in the field, this book is also a great start for students to understand the cooling applications in electronics and an asset to every library in a technical university. Since this book not only gives a critical review of the state of the art but also presents the authors' own results. The book will encourage, motivate and let the reader consider pursuing a research career in electronic cooling technologies.
Download or read book Microscale Heat Transfer Fundamentals and Applications written by S. Kakaç and published by Springer Science & Business Media. This book was released on 2006-05-20 with total page 517 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains an archival record of the NATO Advanced Institute on Microscale Heat Transfer – Fundamental and Applications in Biological and Microelectromechanical Systems held in Çesme – Izmir, Turkey, July 18–30, 2004. The ASIs are intended to be high-level teaching activity in scientific and technical areas of current concern. In this volume, the reader may find interesting chapters and various Microscale Heat Transfer Fundamental and Applications. The growing use of electronics, in both military and civilian applications has led to the widespread recognition for need of thermal packaging and management. The use of higher densities and frequencies in microelectronic circuits for computers are increasing day by day. They require effective cooling due to heat generated that is to be dissipated from a relatively low surface area. Hence, the development of efficient cooling techniques for integrated circuit chips is one of the important contemporary applications of Microscale Heat Transfer which has received much attention for cooling of high power electronics and applications in biomechanical and aerospace industries. Microelectromechanical systems are subject of increasing active research in a widening field of discipline. These topics and others are the main themeof this Institute.
Download or read book Experimental Study on Heat Transfer Characteristics of Microchannel Systems Using Liquid Crystal Thermography written by Roland Ssonko Muwanga and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
