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. Qmax customer requirement then heat pipe is passed test frequency. Heat pipe seminar report, heat pipe research paper, heat pipe applications, heat pipes theory design and applications pdf, heat pipe is widely used nowadays because, objectives of heat pipe, heat pipe working principle, mechanical seminar topics. Heat pipes are referred to as the superconductors of heatdue to their fast transfer capability with low heat loss. An essential guide for practicing engineers and an ideal text for postgraduate students, the book takes a highly practical approach to the. Heat pipe and phase change heat transfer technologies for. Working principle liquid inside the container under its own pressure enters. Convection is usually the dominant form of heat transfer in liquids and gases. Heat pipe principles use 2 phase flow, latent heat of vaporization, and capillary action to circulate a working fluid. Theory of heat pipe porosity in order for the heat pipe to operate the. Transports heat from a heat source to a heat sink works as an isothermalizer why twophase thermal system. How to model a heat pipe heat transfer and fluid flow. Ats engineering ebook advanced thermal solutions, inc.
With central systems, the primary conversion from fuel such as gas or electricity takes place in a. Heat pipe principle it is not within the scope of the article to go into details of heat pipe theory. What is a heat pipe heat pipes basics and technology. A furnace is an equipment used to melt metals for casting or to heat materials to change their shape e. Hp beats laptop model 15p393nr heat pipe failure and. Principles of finnedtube heat exchanger design for enhanced heat transfer 2nd edition by dipl. Heat exchanger design handbook pdf alzaytoonah university. Journals pdf frontiers in heat pipes fhp thermal citeseerx. The basic heat pipe is a closed container whfch contains a capillary wick structure. This method has been used in the aerospace industry for about thr ee decades for supporting systemlevel design analysis. Heat exchangers doehdbk1018193 types of heat exchangers.
This section introduces furnaces and refractories and explains the various design and operation aspects. Mathematical model for heat transfer limitations of heat pipe. In this section we will briefly describe the basic working principle and the performance limits of heat pipes. Convective heat transfer, often referred to simply as convection, is the transfer of heat from one place to another by the movement of fluids. Heat transfer and flow analysis in loop heat pipe with. Introduction loop heat pipe is an efficient heat transfer device. If there is a deficiency of working fluid, the heat pipe may fail because of the inability of any artery to fill.
A heat pipe is a heattransfer device that combines the principles of both thermal conductivity and phase transition to effectively transfer heat between two solid interfaces 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. Heat up the heating end of the heat pipe emperature 700c and dissipate 5 6. So heat pump is essentially a heat pump liftingdevice, the effect is from the surrounding environment to absorb heat, and passes it to theheated object the higher temperature of the object, its working principle and refrigerationmachine with the same, are in accordance with the inverse kano cycle work, just havedifferent operating temperature. Outline from heat pipe to loop heat pipe and capillary pumped loop lhp operating principleslhp operating principles lhp components sizing and fluid inventory lhp operating temperature control lhp startup lhp shutdown lhp analytical modelinganalytical modeling recent lhp technology developments introduction to lhp ku 2015 tfaws 2. Efficient heat transferefficient heat transfer boiling and condensationboiling and condensation small temperature difference between the heat source and. It is called a doublepipe exchanger because one fluid flows inside a pipe and the other fluid flows between that pipe and another pipe that surrounds the first. 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 paper highlights the advancement of heat pipe for hypersonic cruise vehicles. 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.
Their operation is based on the principle of oscillation for the working fluid and a phase change phenomena in a capillary tube. It contains prohibitions in areas where practices or designs are known to be unsafe. This new edition has been revised to include new information on the underlying theory of heat pipes and heat transfer, and features fully updated applications, new data sections, and. 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. First, the working principle of heat pipe is introduced.
Principles of fluid chillers page 4 thermonics corp. A heat pipe is a structure with very high thermal conductivity that enables the transportation of heat whilst maintaining almost uniform temperature along. This work and the related pdf file are licensed under a creative commons. A heat exchanger is a device that is used to transfer thermal energy enthalpy between. Heat pipes are one of the most effective procedures to transport thermal energy. Manufacturing and temperature measurements of a sodium heat pipe. Pdf design guide and heat pipe selection researchgate. The operational principles and the performance characteristics of the different types of heat pipes are described. Common heat transfer fluids for various heat removal temperatures. Thermomechanical design and characterization of flexible. Heat pipes a novel cooling principle for generator. This book provides a practical study of modern heat pipe engineering, discussing how it can be optimized for use on a wider scale. Heat pipes gaugler proposed the principle of heat pipe in 1942 for refrigeration engineering applications.
The transition temperature was reached more rapidly in the cases of high heat input rate for the sodium heat pipe. R sekulib university of kentucky introduction a heat exchanger is a device that is used for transfer of thermal energy enthalpy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a. A rule of thumb for the effective thermal conductivity of a heat pipe is 4000 wmk. When heat is added to water, its temperature rises at a rate of 0. When selecting the diameter and length of heat pipe it is important to consider the orientation with respect to gravity. Heat exchangers jordan university of science and technology. The heat pipe is one of the remarkable achievements of thermal physics.
Introduction heat pipe is a capillary twophase heat transfer device. How to model a heat pipe a brief explanation is provided of a networkbased method that is suitable for modeling constant conductance heat pipes cchps, also called fixed conductance heat pipes or fchps and vapor chamber fins. Historical perspectives, principles of operations, types of heat pipes are discussed. Another drawback of excess fluid is peculiar to heat pipes in space, where in zero gravity the fluid can move about the vapour space, affecting the dynamics of the spacecraft. Fundamentals of hvac controls the application of heating, ventilating, and airconditioning hvac controls starts with an. 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. Loop heat pipe, multiple evaporators, thermal conductance, network model analysis, two phase flow. The principle of wick heat pipe operation is illustrated with the aid of fig.
Pdf heat pipes and its closed twophase thermosyphons are highly efficient heat. Research paper thermomechanical design and characterization of. Beginning with a definition of the problem, including the temperature. Heat pipe working principle seminar projects topics. Pdf basic principles of heat pipes and history researchgate. Heat transfer limitations of water wick heat pipe with sintered capillary structure heat pipe inner diameter 20 mm. However, his principle was not effectively applied and was not widely known until 1963, when grover and his colleagues developed heat pipes for space applications and described the concept with the name of heat pipe.
Heat pipes for computer cooling applications intechopen. Handbook of heating, ventilation and air conditioning. Easy to understand, learn the working and principle of heat pipes. The heat exchanger also referred to as an evaporator moves heat away from the.
A loop heat pipe with coherent pores integrated to the heat source is considered as a calculation model in this paperfig. Although often discussed as a distinct method of heat transfer, convective heat transfer involves the combined processes of unknown conduction heat. Pdf heat pipe in modern heat exchangers researchgate. 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. This portable document format \pdf\ file contains bookmarks, thumbnails, and hyperlinks to help you navigate through the document. Karl ponweiser institute for thermodynamics and energy conversion vienna university of technology vienna, austria published by wseas press. In this chapter, a cpu thermal design power tdp, cooling methods of electronic equipments, heat pipe theory and operation, heat pipes components, such as. Heat pipes are recognised as one of the most efficient passive heat transfer technologies available. This paper presents a planar cooling strategy for advanced electronic applications using heat pipe technology. There are many types of heat exchangers applied in the process industry. The vapor then travels along the heat pipe to the cold.
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. Modelling and performance of heat pipes with long evaporator. The original heat pipe operating principle was developed by richard s. 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.
1575 643 1335 581 1090 1506 199 427 413 567 498 293 583 828 488 731 1167 489 746 124 1359 356 765 1427 1172 356 1532 1152 177 221 616 1450 1192 809 978 1482 1481 1217 1065