Thermalfluidspedia historical development of heat pipes. This book introduces operational and design principles for heat pipes. Abstract this study presents a novel pulsating heat pipe php concept that is functional even when php is with fewer turns and is operated horizontally. Design tools based on computational fluid dynamics simulation and hshptm heat sinkheat. Nov 25, 2016 heat pipe science and technology, second edition by dr. I am trying to design a pulsating heat pipe with a capacity of 4050w for cooling of electronics components in cpu. Pdf cfd simulation of a pulsating heat pipe using ansys fluent. A novel design of pulsating heat pipe with fewer turns applicable to. Bahman zohuri this book provides a practical study of modern heat pipe engineering. Amir faghri written to cover simple, intermediate, and advanced approaches to the theoretical and experimental analysis of heat pipes, this second edition emphasizes the physics and mathematics of heat pipes as well as the related technological and experimental issues. A total of 10 parallel interconnected rectangular channels forming a meandering closed loop are engraved on the silicon wafer with a thickness of 1 mm. Peter kew first became involved in heat pipes in the late 1970s as a research officer with international research and development working on a range of heat transfer and energy conservation projects, including heat pipe development which was then led by david reay. Dec 14, 2007 heat pipes are widely used heat transfer devices in the electronic cooling area. In this paper, a novel pulsating heat pipe php design, which combines features of php and capillary microstructures, is presented to enhance heat transfer of electronic printed circuit boards pcb.
These tubes are evacuated and partially filled with the working fluid. A novel design of pulsating heat pipe with fewer turns. Recent citations effect of filling ratio and orientation on the performance of a multiple turns helium pulsating heat pipe monan li. Heat pipes, 6th edition, takes a highly practical approach to the design and selection of heat pipes, making it an essential guide for practicing engineers and an ideal text for postgraduate students. Computational model of miniature pulsating heat pipes. Understanding effect of operating parameters on thermal. Design and operation of a cryogenic nitrogen pulsating heat pipe to cite this article. Heat pipes are referred to as the superconductors of heatdue to their fast transfer capability with low heat loss.
Design, applications and technology mechanical engineering theory and applications 97815369082. For cooling of electronic or electric equipment, there is a growing industrial demand of highperformance thermal links. Paper open access design and operation of a cryogenic. Flow and heat transfer in a dimpled pipe corrugated pipe in ansys fluent. Schematic of a pulsating heat pipe and its design variations 2. Thermomhydrodynamics of closed loop pulsating heat pipes. Martinez prepared by sandia national laboratories albuquerque, new mexico 87185 and livermore, california 94550 sandia national laboratories is a multiprogram laboratory managed and operated by sandia corporation. Jun 10, 2017 this is how you can design analyzed heat pipe. Energy conservation and waste heat recovery 4,998 views.
Design considerations when using heat pipes electronics cooling. This latest edition of has been extensively revised and expanded, with new information on the underlying theory of heat pipes and heat transfer, data on pulsating heat pipes and capillary pumped loops, new chapters on design and on electronics cooling applications, and updated applications. This type of heat pipe does not require a wick structure to function. Pulsating heat pipe is a kind of highly efficient heat conductor in which the latent heat of evaporation is used to transport great amounts of heat in the presence of only small differences in temperature. Micro flat plate pulsating heat pipe fpphp was fabricated using drie mems technique. Pdf design of a hydrogen pulsating heat pipe researchgate. There may exist an optional adiabatic zone in between evaporator and condenser. Starting with fundamental presentation of heat pipes, the focus is on oscillating. A pulsating heat pipe php 1 is a passive and extremely efficient way of exchanging heat. Mar 01, 2011 a compact micro pulsating heat pipe was developed and tested to investigate thermal performance. Access cloudbased heat pipe selection software from anywhere, anytime. How should i go about designing a wickless heat pipe. The main reason for this is the two phase phenomenon happening inside phps with the oscillatory motion of the bubbles. Loop heat pipe with coherent porous wick since the porous material used for current heat pipes is usually stochastic structure, it is hard to apply analytical or numerical methods for design optimization.
The bends are placed at the evaporator and condenser areas of the heat pipe. Oscillating heat pipes ohp, also referred to as pulsating heat pipes php, are a relatively new development in the field of heat pipe technology. Heat pipe design and technology modern applications for. This book is an essential resource and learning tool for senior undergraduate, graduate students, practicing engineers, researchers, and scientists working in the area of heat pipes. Heat pipe design guidance for heat sink integration. This handbook provides all aspects of piping design starting from fluid properties, stress analysis, construction and fabrication details, compensating methods for thermal expansion, erection etc.
When heat pipes are used to move heat vs spread heat this is a twostep process. Schematic of a typical pulsating heat pipe with design variations. Pdf cfd simulation of a pulsating heat pipe using ansys. Feb 05, 2018 its the two phase heat transfer device suitable for low power applications such as electronic cooling. Heat transfer enhancement of planar pulsating heat pipe. He is the author of five books, over 300 archival technical publications. The first step in selecting a heat pipe working fluid and envelopewick material is to determine the operating temperature range.
It consists of a closed capillary tube folded into meander and partially filled with a liquid. On the design fundamentals of pulsating heat pipes. A heat pipe is a heat transfer device that combines the principles of both thermal conductivity and phase transition to effectively transfer heat between two solid interfaces. An introduction to pulsating heat pipes may 1, 2003 sameer khandekar heat pipes design, liquid cooling, number 2, php, pulsating heat pipe, volume 9 modern electronics thermal management faces considerable challenges in the wake of component miniaturization, which has led to higher demands on net heat flux dissipation. The vapor then travels along the heat pipe to the cold interface and condenses back into a liquid releasing the latent heat. Pulsating heat pipe pulsating heat pipe has many numbers of uturns of tube with capillary diameter. Heat pipes are widely used heat transfer devices in the electronic cooling area. In order to surpass this inconvenience, in the past decades, novel, twophase passive systems without wick structure, like pulsating heat pipes. The pulsating heat pipe affords a highly effective heat transfer component. They differ by their geometry and a mechanism of fluid transport inside the heat pipe. Moreover, an optional adiabatic section may be placed between the. The monogroove heat pipe developed by grumman utilizes an extruded cross section which separates the vapor space from the liquid return path fig. Oscillating heat pipes ohps have high heat spreading performance and are capable of removing higher heat fluxes. For example, choice of the wick and case material eliminates many candidate working fluids often including water due to.
Where can i find detailed design guide for pulsating heat pipe. At the hot interface of a heat pipe a liquid in contact with a thermally conductive solid surface turns into a vapor by absorbing heat from that surface. In this chapter, we present the current level of understanding and existing approaches to the php modeling and design. Ats engineering ebook advanced thermal solutions, inc. The pulsating heat pipe assisted tool holder was designed and fabricated.
Traditional pulsating heat pipe with fewer turns is. This book also includes detailed descriptions on how an oscillating heat pipe is fabricated, tested, and utilized. This study presents a novel pulsating heat pipe php concept that is functional even when php is with fewer turns and is operated horizontally. In this work, novel and unique generic designs of compact heat exchangers were proposed,especially for use in nuclear safety applications, which were based on a pulsating heat pipe phpconcept. Originally developed and patented by hisateru akachi in 1990, ohps consist of a long meandering tube which is heated and cooled at. Development of a compact micro pulsating heat pipe asme. Many of the present days electronic devices require cooling beyond the capability of conventional metallic heat sinks. Celsia is a custom heat sink manufacturer specializing in vapor chamber and heat pipe thermal assemblies.
Computational model of miniature pulsating heat pipes r. Written by a former senior chief scientist at lockheed who has also worked for westinghouse and the u. However, in an actual application when a heat pipe is soldered or epoxied to the base of a heat sink, the effective thermal conductivity of the heat pipe may be. Thermal performance of closed loop pulsating heat pipe using. Originally developed and patented by hisateru akachi in 1990, ohps consist of a long meandering tube which is heated and cooled at various points along its length. To maintenance of all pipeworks whether underground or overhead, carrying any fluid like water, oil, air, industrial gases like oxygen, nitrogen, acetylene etc. When the diameter of the tube is so small, preferably pulsating heat pipes php, also called oscillating heat pipes, belong to the thermal system category of heat pipes, twophase passive thermal devices used to transfer heat from a hot source to a cold region, with very high equivalent thermal conductivity, higher than any usual metallic material, light, and able to manage high heat fluxes. This latest edition has been extensively revised and expanded, with new information on the underlying theory of heat pipes and heat transfer, data on pulsating heat pipes and capillary pumped loops, new chapters on design and on electronics cooling applications, and updated applications. Jun 18, 20 a heat pipe heat exchanger is a simple device which ismade use of to transfer heat from one location to another,using an evaporationcondensation cycle. A heat pipe is essentially a passive device that can. A novel double pipe pulsating heat pipe design to tackle inverted. Heat transfer analysis of shell and tube heat exchanger using baffles for water flow parti duration. A compact micro pulsating heat pipe was developed and tested to investigate thermal performance.
This book presents current research and development related to the design, applications and technology of various heat pipes, including conventional heat pipes and thermosyphon, pulsating heat pipes, loop heat pipes, and variable conductance heat pipes. Abstract pulsating heat pipes phps are the new addition to the wickless heat pipe family. In addition to the conventional heat pipes described above, it is worthwhile to mention a new type of heat pipe, the pulsating heat pipe php, which is made from a long capillary tube bent into many turns, with the evaporator and condenser sections located at these turns. An introduction to operational and design principles, this book explores the use of heat pipes, particularly in highheat flux applications and in situations in which there is any combination of. One such thermal device is the recently invented pulsating called also oscillating heat pipe php.
A practical approach provides a practical study of modern heat pipe engineering in nuclear and solar energy applications, discussing how it can be optimized and made more costeffective for use on a. Pulsating heat pipes phps are the new addition to the wickless heat pipe family introduced by akachi in 1990s, in last few decades this device acts as a promising source for cooling electronic devices where temperature difference between. One solution to remove excess heat is by utilization of heat pipes which are employed to remove the excess heat by directly attaching them to the heat source. The liquid pressure decreases as it flows from the condenser to the evaporator. Even the name is heat pipe,but working is very much different than the conventional heat pipes.
In this chapter we will discuss applications of heat pipes to energy system. Pulsating heat pipes are different from conventional heat pipes in design and working principle. An introduction to pulsating heat pipes electronics cooling. Simplifications and assumptions made in all the modeling approaches developed so far render them unsuitable for engineering design.
Calculate accurate savings predictions thanks to flexible hours of operation input. At any cross section of the heat pipe, a pressure differential exists between the vapor and liquid phases. The issue of compatibility and the results of life tests on heat pipes and thermosyphons remain critical aspects of heat pipe design and manufacture. The vapor pressure decreases as it flows from the evaporator to the condenser. Amir faghri is currently a professor of mechanical engineering at the university of connecticut, which he joined in 1994 and where he served as the head of the mechanical engineering department 19941998 and as dean of the school of engineering 19982006. A heat pipe heat exchanger is a simple device which ismade use of to transfer heat from one location to another,using an evaporationcondensation cycle.
Comprehensive thermal characterization of the new compact heat exchangers was undertaken. Heat pipe operating principles pressure drops operating temperature functional types of heat pipes heat pipe operating characteristics heat pipe design and selection design considerations mostly for vendors selecting heat pipes as part of thermal control system and. A pulsating heat pipe php 1 is a passive and extremely efficient way of exchanging heat between a hot source and a cold one. There are a large number of other compatible envelopefluid pairs that are used at other temperature ranges. Design considerations when using heat pipes electronics. Spaghetti heat pipes the small diameter 3 mm bendable ss spaghetti heat pipes are similar to pulsating heat pipes, but have a compact condenser and large surface evaporator. Pulsating heat pipe pulsating or oscillating heat pipe, invented in early 1990s present promising alternatives for the removal of high localized heat fluxes to provide a necessary level of temperature uniformity across the components that need to be cooled. Two configurations of pulsating heat pipe i open loop ii closed loop proc. In addition, the author discusses heat pipe technology pertinent to the design and application of selfcontrolled, variable.
The pulsating heat pipes php, also called oscillating heat pipes, belong to the thermal system category of heat pipes, twophase passive thermal devices used to transfer heat from a hot source to a cold region, with very high equivalent thermal conductivity, higher than any usual metallic material, light, and able to manage high heat fluxes. An example of a spaghetti heat pipe filled with ammonia, shown in is disposed inside the refrigerator chamber in such a way that food can be kept within the. This article is intended to offer design guidance when using heat pipes for the most prevalent types of electronics applications. The oscillating or pulsating heat pipe php is another. Furthermore, research and development for new heat pipes such as loop heat pipes, micro and miniature heat pipes, and pulsating heat pipes, has matured enough for use in various applications.
Pulsating heat pipes are made from a long capillary tube which is bent multiple times, or from a rectangular plate with capillary channels manufactured in it. Oscillating heat pipes ohps use thermally driven, twophase fluid flow to rapidly transfer heat between heat sources and heat sinks. Once the correct heat pipe s have been identified the next step is integration into the heat sink. Heat sink design and optimization is done jointly between our us headquarters and taiwan facilities, while heat sink manufacturing is done exclusively at the latter. Whether youve loved the book or not, if you give your honest and detailed thoughts then people will find new books that are right for them. The heat pipe temperature reaches the water temperature in about 25 seconds, while the copper rod reaches just 30c after 200 seconds. This book presents the fundamental fluid flow and heat transfer principles occurring in oscillating heat pipes and also provides updated developments and recent innovations in research and applications of heat pipes. To learn more about the ohp technology and how we innovate custom thermal solutions, click on a topic below. As with any design process, many of the decisions that must be taken are interrelated and the process is iterative. They are made from a long continuous capillary tube bent into many turns, with the evaporator and condenser sections located at these turns. This chapter discusses the main components of the heat pipe and the materials used.
The simulation of a 2d single loop pulsating heat pipe using. Pulsating heat pipes phps are passive heat transfer devices where the heat transfer is much more higher as compared to the general heat transfer devices such as metal fins. However the principal drawback of such systems is the high production costs. I do not have much experience with lab scale equipment, but can provide some points which might help. Mathematical modeling of pulsating heat pipes through first principles is a contemporary problem which remains quite elusive. Although a plethora of designs of classical heat pipes are available, recent industry trends have frequently shown the limitations of these. This book provides a practical study of modern heat pipe engineering, discussing how it can be optimized for use on a wider scale. Generate performance reports, psychrometrics and dimensional drawings. The thermal resistance for the proposed design is only half of the single tube design.
A loop heat pipe with coherent pores integrated to the heat source is considered as a calculation model in this paperfig. May 01, 2003 an introduction to pulsating heat pipes may 1, 2003 sameer khandekar heat pipes design, liquid cooling, number 2, php, pulsating heat pipe, volume 9 modern electronics thermal management faces considerable challenges in the wake of component miniaturization, which has led to higher demands on net heat flux dissipation. Heat input and output are through the flat face on top of the vapor space. Overall, heat pipes theory, design and applications is an excellent book that covers the subject in great depth for the benefit of heat pipe designers and users. A good description of the history of the heat pipe technology can be found in an early article published by yale eastman currently a director of act in scientific american in may 1968. Briefly here both cchp and vchp are touched upon again. Heat pipes are remarkably versatile devices, capable of being manufactured at the very small scale such as for cooling electronic devices and on a much larger scale such as for. Pdf toward a design of a micro pulsating heat pipe. We also touch baseup heat pipe applications in electronic manufacturing where the fast central processing units cpus need to be cooled down and how heat pipe can be used as a heat. What is a heat pipe heat pipes basics and technology.
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