Applied thermal engineering disseminates novel research related to the design, development and demonstration of components, devices, equipment, technologies and systems involving thermal processes for the production, storage, utilization and conservation of energy, with a focus on engineering application. Heat pipes have emerged as an effective and established thermal solution, particularly in high heat flux applications and in situations where there is any. The wick is designed to provide a capillary pumping action, as described below. Condenser temperature, sensor is embedded between hp and condenser section of heat pipe. Technical note design and performance prediction of a. In this qpedia magazine issue 96 vineet barot discusses effective thermal conductivity of a heat pipe for a reference data sheet on he. Effective thermal conductivity of heat pipes springerlink. Jouhara school of engineering and design, brunel university, uk abstract interest in the use of heat pipe technology for heat recovery and energy saving in a vast range of engineering applications has been on the rise in recent years. 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. Effective thermal conductivity of a heat pipe youtube. Experimental method figure 2 below shows an experimental test rig that used for the experiment.
A typical heat pipe consists of a sealed pipe or tube made of a material that is compatible with the working fluid such as copper for water heat pipes, or aluminium for ammonia heat pipes. Power generation from waste heat using heat pipe and. Pdf this book provides a practical study of modern heat pipe engineering, discussing how it can be optimized for use on a wider scale. 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. Hence, other than thermal design of the heat pipe, mechanical design of the. When heat pipes are used to move heat vs spread heat this is a twostep process. He addressed that for design issues of such thermal system, the crossover radius is utilized. 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 pipe science and technology mechanical engineering. A loop heat pipe with coherent pores integrated to the heat source is considered as a calculation model in this paperfig. For example, choice of the wick and case material eliminates many candidate working fluids often including water due to. Heat pipe design guide thermal management technologies. The operating temperature of working fluid within the heat pipes is 108109 c, the volume of working fluid to be filled into the heat pipes is 20 ml.
Several heat pipes were designed and manufactured to study the effect of the working fluids, container materials, and the wick structures on the heat transfer mechanism of the heat pipes. Thermal design methods and processes for shellandtube, compact, and gasketedplate heat exchangers. With good design ideas, it is possible to use heat pipes to heat or cool adsorbers, which put the adsorbers in contact with the heat pipe working medium for heating and cooling 8. The heat transfer of an airtoair heat pipe heat exchanger hphex with counter flow and a hightemperature range was modeled. Haringx 10 modeled the bellow as the combination of annular plates connected by elastic cylinders and derived. An essential guide for practicing engineers and an ideal text for postgraduate students, the book takes a highly. For a properly designed heat pipe, the effective thermal conductivity can range from 10 to 10,000 times the thermal conductivity of copper, depending on the length of the heat pipe. Thermal numerical model of a high temperature heat pipe. Also, the effect of the number of wick layers on the effective thermal conductivity and the heat transfer characteristics of the heat pipes have been investigated.
In this paper a computer simulation was developed by matlab to design the heat pipe heat exchangers. The maximum thermal load was 1 kw and the operating temperature of the heat pipe was around 250 the liquid fill charge was adjusted so that the first condenser section may work as an evaporator when the original evaporator was inactive in a vertical configuration. Correlations for the design of twophase flow heat exchangers. The pipe seal, purity of the materials used in the wick structure and cleanliness of the internal chamber are all factors that effect the long term performance of a heat pipe. In this present work the study and analysis of natural convection flow of water through vertical pipe is done. 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.
Modeling of the heat pipe heat exchangers for heat recovery. The main part is a sealed metal tube in which the air and other impurities must have been excluded out to maintain a micronegative pressure and. Selection, rating, and thermal design, second edition 9780849314155 by sadik, kakac and a great selection of similar new, used and collectible books available now at great prices. Various heat pipe remote heatexchanger for laptop pc 9. The heat pipe has three major operating zones, namely evaporator, adiabatic section and condenser, see figure 1. Numerical analysis of thermal performance of flat heat pipe. The application of heat pipes should be considered when the thermal design is either conduction limited or when nonthermal goals such as weight cannot be achieved with other materials such as. Numerical analysis of thermal performance of flat heat pipe d. Pdf design guide and heat pipe selection researchgate. K a walshe air naturel heat sink is being used, its thermal heating time constant might be measured in minutes rather than milliseconds for the junction. All baknor heat pipes are 100% functionally tested. Pdf heat pipe in modern heat exchangers researchgate. The heat exchanger contains 7 tubes and 600 mm length shell diameter 90 mm. Heat pipe design effective heat pipe thermal resistance.
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. Depending upon the design constraints and thermal requirements, two phase cooling technology has emerged with different options that can be considered in the. Fujikura thermal technology overview thermal technology divisiontt. Ats engineering ebook advanced thermal solutions, inc. Thermal conductivity determination by lagged pipe apparatus n b totala 1, pravin arjun kasab 1, ravi babasaheb rathod and swapnil sanjay gunde corresponding author. The hphex was constructed from sodiumstainless steel sts heat pipes hps using a staggered configuration. Thermal spreading resistances for different materials.
Evaporator temperature of heat pipe, measurement on heat pipe top side. Heat pipes with variable thermal conductance property. What is a heat pipe heat pipes basics and technology. Heat loss and temperature profile along an insulated pipe. As with any design process, many of the decisions that must be taken are interrelated and the process is iterative. Analysis for critical radius of insulation for a cylinder. Qmax test method for heat pipes heat sink design, heat. Pdf thermal design of spiral heat exchangers and heat.
Do you have an option in genie that allows for a customized placement of the heat pipe. It emphasizes the physical aspects of heat pipe behavior and develops design formulas on the basis of mathematical models and empirical observation. Heat pipe design guidance for heat sink integration. The heat pipe is partially filled with a working fluid and then sealed. This program can be considered as a simple tool for modeling and designing heat pipe heat exchangers. Other variables which affect a heat pipes thermal conductivity include geometry, wick structure and working fluid. At this juncture, the only placement options are the number and diameter of the pipes and the axis direction. The crossover radius is defined as a radius greater than the critical radius such that the heat transfer with the corresponding amount of.
High performance pga lga summary of cooling design trend for desktop pcs 8. We then present a novel design for a concentric cylindrical teg system that addresses the existing weaknesses of the heat exchanger. Just as the steady state values quoted allow for various. In this study includes what is the effect of the physical parameters of tube like diameter, length and heat flux on the outlet. Kamaraj b indian institute of technology madras, a refrigeration and airconditioning laboratory, department of mechanical engineering, b department of metallurgical and materials engineering, chennai, tamilnadu, india 60036. Heat pipes are attractive because they can typically carry 100 or more times as much heat as an. Design and technology of heat pipes for cooling and heat. Rapid heat sink thermal analysis and design utilizing heat. As with any heat pipe heat sink design, size the heat pipe with an additional 25% thermal headroom. Some bldg energy codes give allowable uvalue based on a weighted average for the. 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. Heat pipe design handbook, volume 1 internet archive.
Thermal systems usually demand some services as electrical supply for power or at least for control, water intake and exit, air intake and exit, fuel supply and flue stack, etc. Heat sinks, thermoelectrics, heat pipes, compact heat exchangers, and solar cells, second edition, is a significantly updated new edition which now includes a chapter on thermoelectrics it covers thermal devices such as heat sinks, thermoelectric generators and coolers, heat pipes, and heat exchangers as design components in larger systems. Figure 7 shows a flat pipe design, they can be used as heat spreaders. The helix angle of helical baffle will be varied from 00 to 200. In the case of the elementary pipe design, liquid returns from the condenser via a wick structure.
A novel design for a thermoelectric generator for waste. This book provides a practical study of modern heat pipe engineering, discussing how it can be optimized for use on a wider scale. Acts expertise with heat pipe technology can find a thermal solution for your industry. Heat loss and temperature profile along an insulated pipe simulated with mathematica 9 and floefd 11. Design and production of high temperature heat pipe heat. Once the correct heat pipe s have been identified the next step is integration into the heat sink. Heat pipes in solar thermal collectors enable to reduce the temperature loads in the.
When the heat source is much smaller than the heat sink base, a flat. Heat pipe engineering ebook advanced thermal solutions. 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. New space satellites designs, from telecommunication satellite to microsatellite, include thermal stabilization systems which are based on heat pipes. Remote fin stacks heat exchangers are a perfect example. Wtl heat pipe heat pipe hp iscelebrated as an excellent heat transfer component, consisting of three parts called evaporating section,adiabatic section and condensation section. Written by a former senior chief scientist at lockheed who has also worked for westinghouse and the u. Concerned with the energy used to provide heating, cooling and ventilation of buildings introduction to heat.
It manifests itself as either molecular vibration within a substance or as an electromagnetic radiation. Butane heat pipes for stagnation temperature reduction of. Adiabatic temperature of heat pipe, measurement on heat pipe top side. Design and thermal analysis of heat exchanger with two.
The main cause is the heat pipe input power exceeds the design heat transport capacity of the heat pipe. Typically, a vacuum pump is used to remove the air from the empty heat pipe. This method has been used in the aerospace industry for about thr ee decades for supporting systemlevel design analysis. Thermal design of spiral heat exchangers and heat pipes through global best algorithm article pdf available in heat and mass transfer june 2016 with 1,299 reads how we measure reads. Thermomechanical design and characterization of flexible. Heat pipes are an extremely effective method of reducing hot spot temperatures and increasing allowable power in a system by moving heat to an external sink or spreading heat along a surface. T t1t2 baknor heat pipe design guide designed by baknor or. Heat pipe science and technology mechanical engineering book. Design considerations when using heat pipes electronics. Faculty of mechanical and manufacturing engineering. Modelling of the thermal behaviour of heat pipes b. In view of the above devices also have a transient thermal resistance value quoted. The use of heat pipes in thermal management is increasing rapidly as power densities in electronics continue to rise.
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