Double pipe heat exchangers have a simple construction. All the heat exchangers are designed based on the function it fulfills in a process. Che 120b heat exchangestheory chemical engineering. Fluid engine oil sea water inlet temperature, c 65 20 outlet temperature, c 55 25 heat load, kw 117. Theoretical determination of effectiveness for heat pipe heat. A heat pipe heat exchanger hphe is a special type of heat exchanger using the excellent thermal properties of the heat pipes.
An odd number of tube passes is seldom used except the 11 exchanger. Heat exchangers 73 individual thermal resistances of the system. Put in a load and a pressure and out pops the answer. Introduction a heat exchanger is a device that is used to transfer thermal energy enthalpy between two.
The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. They are fairly cheap, but the amount of space they occupy is generally high compared with the other types. The heat exchangers are manufactured in different types, however the simplest form of the heat exchanger consist of two concentric pipes of different diameters known as double pipe heat exchanger. 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. Shellandtube heat exchangers can have multiple passes, such as 11, 12, 14, 16, and 18 exchangers, where the first number denotes the number of the shells and the second number denotes the number of passes. Anatomy of a plate heat exchanger anatomy of a sondex plate heat exchanger is frame. Flow inside double pipe heat exchangers can be cocurrent or countercurrent.
The research is focused on developing a heat pipe heat exchanger for domestic hot water and thermal agent preparation, preheating heating. Double pipe heat exchanger ce 328 spring 2003 objective. Pdf cfd analysis of double pipe heat exchanger with. The condenser is cooled by a liquid heat exchanger into which water. A 12 shellandtube heat exchanger is illustrated in figure 5. Pdf the recovery system consists in a heat pipes based heat exchanger that allows efficient transfer from the waste energy to a heat pump.
This article explains how to dimension a custom flange for a heat exchanger. Valves are used to set up desired flow conditions rate and direction. Three partial differential equations describe heat balances across the tube and shellside liquids, and a heat balance across the tubewall taking into account the heat flow from the shell and. Plates were 510 mm thick with a milled pattern, compared to 0. Che 120b 1 heat exchangestheory the double pipe heat exchanger call the hot stream h and the cold stream c and determine all coefficients w. Design a double pipe heat exchanger with bare inner multitubes that can be used to cool engine oil with cold sea water. Plain tubular exchangers, shellandtube exchangers with plain tubes, and. In a counter flow heat exchanger, the two fluids flow in opposite directions. Double pipe heat exchanger a when the other fluid flows into the annular gap between two tubes, one fluid flows through the smaller pipe. First fluid flows inside the inner pipe while the second fluid flows. The heat pipe exchanger requires only the addition of a second, identical tube sheet and lengthening the heat pipes slightly. In this type of heat exchanger, one fluid flows through the small pipe and another fluid flows through the space between both the pipes 7. Convective heat transfer from the outer tube wall to the outside fluid. Heat exchangers may be classified according to transfer process, construction, flow arrange ment, surface compactness, number of fluids and heat transfer mechanisms as shown in fig.
To demonstrate the basic equations of heat exchanger operation. The principal parts are two sets of concentric pipes, two connecting tees, and a return head and a return bend as shown in fig. The related papers were grouped into two main categories. Heat pipe heat exchanger heat exchanger, which transfers the heat from one medium to another, is the most common thermal equipment in various of industry sectors. Solid model of double pipe heat exchanger with available in use such as tubular type heat exchanger, plate inner circular tube modeled using solidworks type heat exchanger, extended heat exchanger, regenerative heat exchanger. Department of mechanical engineering, university of malaya, 50603 kuala. Lectures 19 applied heat transfer cm3110 1232019 3 t, outer bulk temperature t, inner bulk temperature l but. Usually, we need to figure out the required heat transfer area for a given job, given a flowrate and a temperature difference. First, thermal and fluid dynamical design and then mechanical design. Heat exchangestheory the double pipe heat exchanger call the hot stream h and the cold stream c and determine all coefficients w. This program can be considered as a simple tool for modeling and designing heat pipe heat exchangers. They have modelled the heat transfer from hot fluid to cold fluid using the cfd pa ckage phoenics 3. Background a heat exchanger is a heat transfer device whose purpose is the transfer of energy from one moving fluid stream to another moving fluid stream. Pipe heat exchangers project standards and specifications page 3 of 8 rev.
Double pipe heat exchanger introduction this application models the temperature dynamics of a countercurrent double pipe heat exchanger. Multiple heat pipes or thermosyphons then connect two plate heat exchangers. Heat exchanger, which transfers the heat from one medium to another, is the most common thermal equipment in various of. The design of heat exchangers is done in two steps.
Efficient adsorption refrigerators with heat pipes cooling and. Heat pipes are a promising cooling system due to the fact of high efficiency and non. Alfa laval supplied the first plate heat exchangers. Application of the heat pipe to enhance the performance of the vapor. Amir amini spirax sarco heat pipe heat exchangers hexag. To understand the basic operation of heat exchangers. The simplest heat exchanger is one for which the hot and cold fluids move in the same or opposite directions in a concentric tube or double pipe construction. The theories of transient heat transfer in double pipe heat exchangers were explained and followed by literature correlations.
Abstract heat exchangers are used in industrial processes to recover heat between two process fluids. Hence, such heat exchangers are most favored for heating and cooling of fluids. They are fabricated from two pieces of pipe one inside the other. Design and analysis of a newly installed plate heat. Apart from assuring the certain technological processes.
Thermal characterisation of micro flat aluminium heat pipe. Solid model of double pipe heat exchanger with available in use such as tubular type heat exchanger, plate inner circular tube modeled using solidworks type heat exchanger, extended heat exchanger, regenerative heat. Pdf heat pipes are very flexible systems with regard to effective thermal control. A php heat exchanger has several advantages over conventional heat pipe systems with potentially many applications groll and khandekar. Development aspects of a high temperature heat pipe heat. Institute utilizes a double pipe heat exchanger to facilitate the analysis and understanding of heat transfer inside a heat exchanger. Pdf heat pipe in modern heat exchangers researchgate. Classification according to flow arrangements singlepass multipass. Towards an optimal design of heat pipe equipped heat exchangers. The heat pipe is a kind of heat exchanger with high ability for heat. There are many types of heat exchangers applied in the process industry. A procedures manual was created for the double pipe heat exchanger. Convective heat transfer coefficient of the hotter side.
However, in a heat pipe heat exchanger, the heat pipe not only acts as a. The heat exchanger consists of two thin wall copper tubes mounted concentrically on a panel. Pdf heat pipe heat exchanger for heat recovery in air conditioning. These are typically used in applications where there is a ducted exhaust stream. This has been shown in the performance silica gelwater adsorption chiller, in which platefin heat exchanger has been used as an adsorber 9. The hot and cold fluids enter at the opposite ends. A procedure for use of the equipment and the software was outlined. Air that is exhausted from a building, to maintain favorable indoor air quality, has been cooled summer or heated winter to the typical space temperature of 70 to 75f. The counter flow design is most efficient, in that it can transfer the most heat from the heat transfer medium. Specific heat capacity of air at constant pressure. Modeling of the heat pipe heat exchangers for heat recovery. To determine the overall heat transfer coefficient for the double pipe heat exchanger for countercurrent flow and parallel or cocurrent flow.
They are widely used in space heating, refrigeration, air conditioning, power stations, chemical plants, petrochemical plants, petroleum refineries, natural. Cfd study of helically coiled double pipe heat exchangers for laminar flow situations were carried out by rennie and raghavan 2005, 2006a. Heat pipe heat exchanger with two levels of isolation for. Todays hvac and process engineers may choose any number of pipe sizing programs for steam and condensate applications. The flow of water through the center tube can be reversed for either countercurrent or parallel flow. Heat exchangers are used in both cooling and heating processes. Pdf application of heat pipe heat exchangers in heating. Combining each of these resistances in series gives.
Pulsating heat pipe based heat exchangers for iit kanpur. Its widely used in chemical, energy, machinery, transportation, refrigeration, air conditioning and aerospace fields. The proposed heat pipe heat exchangers show a good thermal response and could be used to heat and desorb the porous sorbent bed up to 300c and to cool down again to the ambient temperature due. Usually, we need to figure out the required heat transfer area for a given job, given a flowrate. This calculates the required heat transfer surface and pressure drop for the heat exchanger. Design and analysis of a newly installed plate heat exchanger. From the internal diameter b the flange dimensions are determined step by step on the basis of a number of simple rules. Fluid engine oil sea water inlet temperature, c 65 20 outlet temperature, c 55 25 heat.
However, since double pipe heat exchangers are simple, they are used to teach heat exchanger design basics to students as the fundamental rules for all heat exchangers are the same. Double pipe heat exchangers are normally designed in a hairpin shape and are fabricated in accordance with asme code. Experimental study of heat transfer in a heat pipe iopscience. The temperature difference between the fluid and the wall varies along the length of the heat exchanger. Most actual heat exchangers of this type have a mixed flow pattern, but it is often possible to treat them from the point of view of the predominant flow pattern. Introduction a heat exchanger is a device that is used to transfer thermal energy enthalpy between two or more fluids, between a solid. Although the necessary equations for heat transfer and the pressure drop in a double pipe heat exchanger are available.
In developing our range of plate heat exchangers, we have focused on costefficiency. One common characteristic that can be used to categorize. The first is conduction, which is defined as transfer of heat occurring through intervening matter without bulk motion of the matter. They can easily be implemented as heat exchangers inside. Water flows inside the inner pipe and steam flows through the annulus formed between the two pipes. Counter flow heat exchanger in counter flow heat exchangers the fluids enter the exchanger from opposite ends. Sondex frames are designed according to prevalent rules and legislations and comply with international standards. The overall heat transfer coefficient of the exchanger is. The hot water flows through the center tube, and cold water flows in the annular region. A heat exchanger is a device that is used to transfer thermal energy enthalpy between two or more fluids, between a solid surface and a fluid. Pdf design of double pipe heat exchanger kirti zare. Types of heat exchangers doehdbk1018193 heat exchangers.
One fluid flows through the inner pipe while the second fluid flows through the annulus between the pipes. For double pipe heat exchanger, the rate of heat transfer may be computed using equation 31. A heat exchanger is a device that is used to transfer thermal energy enthalpy between two or more fluids, between a solid surface and. To study and evaluate the effects of flow conditions and flow configurations on the rate of heat transfer through thin walled tubes.
Klm technology group process design of double pipe. Heat pipe heat exchangers could be employed as runaround coils in air conditioning systems for enhanced dehumidification and cooling. Heat exchangers are typically classified according to flow arrangement and type of construction. Because heat exchangers come in so many shapes, sizes, makes, and models, they are categorized according to common characteristics. The end result is a feasible flange with dimensions that can be used to do a stress analysis with, for example, the p3 engineering ves software. Dimensioning a heat exchanger flange p3 engineering. Rld mmm steam condensate pipe sizing steam and steam heat. The goal of this study is to develop an operational model for the thermal design of. The amount of heat transfer per section is small, that makes the double pipe heat exchangers a suitable heat transfer device in applications where a large heat transfer surface is. Thermal and fluid dynamical design is the main and substantial step to heat exchanger design. A heat exchanger is a system used to transfer heat between two or more fluids. Frame it is important that the frame is strong, rigid, and durable, as it is the foundation of any plate heat exchanger. An overview of heat exchanger design problems, a summary of key issues to cover in the design process, and a design methodology of heat exchangers is presented in this chapter. Aug 26, 2002 a procedures manual was created for the double pipe heat exchanger.
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