Heat pipes, i am obliged to point out, are awesome. The work was administered by the goddard space flight center, greenbelt, maryland, and mr. In the short heat pipe extreme 34 length, this effect is nearly zero, so please consult with wakefieldvette engineers to find the right solution for your application. T t1t2 baknor heat pipe design guide designed by baknor or we build to your print custom packaging solutions metal components sub. Show full abstract lockheed who has also worked for westinghouse and the u. The working fluid used was r4a and the correlations. As billy mentioned, todays topic is heat pipe design and modeling. Heat pipe 1piece vapor chamber 2piece vapor chamber 20 heat pipes bend radius 3x diameter of heat pipe. Is there a a free software for designing heat pipes heat exchangers used in air conditioning systems hvac. The heat pipe is composed of a container lined with a wick that is filled with liquid near its saturation temperature. Transports heat from a heat source to a heat sink works as an isothermalizer why twophase thermal system. Chen1 1department of mechanical engineering, national taiwan university, taipei, taiwan 2department of general education, national defense university, taipei, taiwan in the present study, the loop heat pipe lhp was miniaturized for application to electronic cooling.
Mathematical modeling, numerical simulation and statistical. This article is intended to offer design guidance when using heat pipes for the most prevalent types of electronics applications. Small heat pipe assemblies low heat dissipation from 10 to 100w allow increased heat sink performance within the volume available with little potential impact on the existing system design. Apr 29, 2016 this section covers the fundamental theory behind the heat pipe based on different research papers and books available at present time in order to open a clear path for reader to design and fabricate their required heat pipe within their applications. Particular attention is given to the heat pipe without wick material in the. When somebody first explained to me how they work, i was like, no way.
The heat pipe employs a twophase process in which a liquid is evaporated inside the pipe by heat input at one end. Hence, other than thermal design of the heat pipe, mechanical design of the. The purpose of the heat exchanger is to recover heat from the moist waste air stream to preheat the fresh incoming air. Heat pipe science and technology is to provide a greater understanding of the fundamentals, principles and technologies associated with the design and operation of heat pipes and thermosyphons and their optimal connection to active systems such as heat pumps, coolers, refrigerators, power sources, space components and future thermal applications. In this chapter, a cpu thermal design power tdp, cooling methods of electronic equipments, heat pipe theory and operation, heat pipes components, such as the wall material, the wick structure, and. Figure 2 compares the heat transport for heat pipes with different diameters. This book provides a practical study of modern heat pipe engineering, discussing how it can be optimized for use on a wider scale. Open heat pipe design handbook this handbook was prepared under nasa contract nas523406, updating of a heat pipe design and applications handbook. Heat pipe design handbook, volume 1 internet archive. So the goals of todays webinar is to provide you with the knowledge and tools required to implement a heat pipe solution into your system.
This webinar will provide you with an understanding of heat pipe operation and performance, design guidelines to integrate heat pipes into your system, and provide the necessary tools to. Beginning with a definition of the problem, including the temperature. Heat pipes employ phase change to transfer thermal energy from one point to another by the vaporization and condensation of a working fluid or coolant. This book presents current research and development related to the design, applications and technology of various heat pipes, including conventional heat pipes. In this chapter, a cpu thermal design power tdp, cooling methods of electronic.
Pressfitting the heat pipe into a fixture andor machining the heat pipe surface to a desired flatness value requires a thicker heat pipe wall to withstand the mechanical stresses involved in those procedures. Heat pipes and its applications lunds tekniska hogskola. Heat pipe design and technology modern applications for. Is there a a free software for designing heat pipes heat. The heat pipe is a vaporliquid phasechange device that transfers heat from a hot reservoir to a cold reservoir using capillary forces generated by a wick or porous material and a working fluid. However, the operational temperature of the heat pipe also affects the sonic limit of the heat pipe. The resulting vapor is condensed back into the liquid by heat removal at the pipe s other end. Heat pipes, 6th edition, takes a highly practical approach to the design and. Nielsen book data summary 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.
Nov 01, 2004 small heat pipe assemblies low heat dissipation from 10 to 100w allow increased heat sink performance within the volume available with little potential impact on the existing system design. In this chapter, a cpu thermal design power tdp, cooling methods of electronic equipments, heat pipe theory and operation, heat pipes components, such as the wall material, the wick structure, and the working fluid, are presented. Heat pipes for computer cooling applications intechopen. Micro heat pipe article about micro heat pipe by the free. The book is a useful reference for those with experience and an accessible. 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 drastically reduced due to the extra thermal resistances added by the bonding. A practical approach provides a practical study of modern heat pipe. The crosssectional area of a heat pipe is the direct function of both the sonic and entrainment limit of the heat pipe. The book consists of fourteen chapters, two appendices, and over 400 illustrations, along with numerous presents basic and advanced techniques in the analytical and numerical modeling of various heat pipe systems under a variety of operating. When used outside of its design heat range, the heat pipes thermal conductivity is effectively reduced to the heat conduction. Garimellab aschool of mechanical, aerospace, and systems engineering, kaist, daejeon 305701, republic of korea. A very small heat pipe that has a diameter between about 100 micrometers and 2 millimeters 0. Heat is absorbed by the evaporating heat pipe fluid and carried to the alumina substrate where it is released by the condensing fluid and transferred through mic case to the heat sink. Heat pipes are used in a wide range of applications, including electronics cooling, diecasting and injection moulding, heat recovery and energy conservation, deicing and manufacturing process temperature control, and in domestic appliances.
The selection of wick and wall materials is based on the criteria discussed in chapter 3. Heat pipes rely on a temperature difference between the ends of the pipe, and cannot lower temperatures at either end below the ambient temperature hence they tend to equalize the temperature within the pipe. Another critical design decision is the type of heat pipe wick that is employed. The heat pipe must also withstand bonding temperatures. Jun 11, 2015 this webinar will provide you with an understanding of heat pipe operation and performance, design guidelines to integrate heat pipes into your system, and provide the necessary tools to run easy. When selecting the diameter and length of heat pipe it is important to consider the orientation with respect to gravity. Heat pipe science and technology mechanical engineering by.
For example, there is an analogy between micro heat pipe operation and functioning of a sweat gland. A loop heat pipe with coherent pores integrated to the heat source is considered as a calculation model in this paperfig. Simulation and cfd analysis of heat pipe heat exchanger. Design and technology of heat pipes for cooling and heat exchange crc press book this book describes the characteristics of heat pipes under steadystate and transient operating conditions. Opentype mini micro heat pipes are suggested in, as a system of thermal control of biological objects and drying technology.
Written by a former senior chief scientist at lockheed who has also worked for westinghouse and the u. Mathematical model for heat transfer limitations of heat pipe. The thermal performance of this complete highpower coupling of transmitter transisfigure 4 ao40 heat pipe extrusion cross section. Numerical simulation of a cylindrical heat pipe and. Efficient heat transferefficient heat transfer boiling and condensationboiling and condensation small temperature difference between the heat source and. This paper considers the thermal design and the experimental testing of a heat pipe thermosyphon heat exchanger for a relatively small commercially available minidrier. The use of heat pipes for the thermal management of notebook computers is a proven and widely applied technology. And yet they persist in existing, and working, in spite of my disbelief. Component cooling, temperature control and radiator design in satellites.
Heat pipe is a capillary twophase heat transfer device. Overallan excellent book that covers the subject in great depth for the benefit of heat pipe designers and usersengineers will no doubt continue to stretch. Heat pipe design methodologies and manufacturing considerations applications for cooling both electrical and mechanical systems the full range of heat pipe classifications, including rotating and revolving, micro, cryogenic, and variable conductance heat pipes, as well as thermal diodes and switches. Most thermal engineers have found it, and we would also recommend, using effective thermal conductivity to model the solid heat pipe. A heat pipe moves heat from spottospot with little loss in temperature. Heat pipe design and modeling heat pipe manufacturer. Thermomechanical design and characterization of flexible. A glass fiber refrasil wick was used in the heat pipe tests. A heat pipe heat recovery heat exchanger for a minidrier. Heat pipes, electronic cooling, wick structure, working fluids, computer.
Opentype minimicro heat pipes are suggested in, as a system of thermal control of biological objects and drying technology. Considering a cylindrical heat pipe, a 2d axisymmetric model was constructed. The total heat load a heat pipe can carry is a function of total length, evaporator and condenser length, diameter, and orientation with respect to gravity. The work describes principle, design and construction of gravity heat pipe ghp and wick heat pipe whp. Figures 6 and 7 are photo illustrations of these heat pipe clamps as a separate assembly and as installed in the spacecraft. Consequently, heat pipes can be a viable and promising solution for this challenge. A heat pipe is a heattransfer device that combines the principles of both thermal conductivity. The use of heat pipes for the thermal management of notebook computers is. Haringx 10 modeled the bellow as the combination of annular plates connected by elastic cylinders and derived.
Dick jansson, kd1k, ex wd4fab and wa1qli, arrl technical. In essence, a heat pipe operates as a heat pump, transporting heat from one end to another where the heat can dissipate. International heat pipe conferences have been conducted, two books on heat pipes have been authored, and numerous papers have been written on the. Mvk160 heat and mass transfer may 7, 2012, lund, sweden heat pipe, selection of working. Micro heat pipe phenomena is often available in nature. 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. 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.
The resulting vapor is condensed back into the liquid by heat removal at the pipes other end. It emphasizes the physical aspects of heat pipe behavior and develops design formulas on the basis of mathematical models and empirical observation. Use of heat pipe cooling systems in the electronics industry. Allows direct contact with heat source 1piece vapor chamber 10mm bend radius along. Methodology to measure the heat pipe performance it is very important to achieve the top wall temperature profile. Project description by means of knowledge about the theory of heat pipes, one is now able to carry out a basic calculation of a heat pipe. Jul 15, 2009 heat pipes, i am obliged to point out, are awesome. Design considerations when using heat pipes electronics cooling. Ats engineering ebook advanced thermal solutions, inc. Micro and miniature heat pipes electronic component coolers. The operating principles, heat transfer characteristics, and fabrication process of memsbased micro. Direct simulation of a heat pipe is difficult due to the complex structure and physics inside the pipe.
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