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 design stages mentioned in the literature can applicable for all the simple designing of double pipe heat exchangers. To study and evaluate the effects of flow conditions and flow configurations on the rate of heat transfer through thin walled tubes. Equation is used when simple counter or cocurrent flows exist. Cfd analysis on double pipe heat exchanger using fe3o4 nano fluid. In a double pipe heat exchanger design, an important factor is the type of flow pattern in the heat exchanger. Introductionhorizontal double pipe heat exchanger uses various inserts inside tube so as to enhance heat transfer and hence increase heat transfer. Double pipe heat exchangers are normally designed in a hairpin shape and are fabricated in accordance with asme code. First fluid flows inside the inner pipe while the second fluid flows in the annular space between the two pipes. Overall heat transfer coefficient for doublepipe heat. Design of this heat exchanger was dependent on heat transfer conditions and related equations.
All about double pipe heat exchangers what you need to know. Researchers have done theoretical as well as experimental analysis of triple concentric pipe heat exchanger. Introduction a heat exchanger is a device that is used to transfer thermal energy enthalpy between two or more fluids, between a solid. The temperature difference between the fluid and the wall varies along the length of the heat exchanger. Counter flow heat exchangers are the most efficient of the three types. Since the exchanger is custom designed, the tube size can be smaller than nps 18 dn 6 mm that is the smallest size in table c. Heat exchangestheory the double pipe heat exchanger call the hot stream h and the cold stream c and determine all coefficients w.
Pipe heat exchanger an overview sciencedirect topics. Checalc chemical engineering calculations to assist process, plant operation and maintenance engineers. The heat exchanger was constructed using galvanized steel for both the tube and shell. There are two concentric pipes with different diameters. The solution of the problem yields the optimum values of inner pipe diameter, outer pipe diameter and utility flow rate to be used for a double pipe heat exchanger.
Condenser heat exchanger is very common in process industry, condensers may be classified in two main types. Heat exchanger performance for optimized geometry 34 table 53. The double pipe heat exchanger is one heat exchanger pipe inside another larger pipe for either counter flow or parallel flow pattern. Experiments were designed and carried out to test the. As its name implies, this type of heat exchanger consists of a shell a large pressure vessel with a bundle of tubes inside it.
One fluid flows through the inside pipe and the other flows through the annulus between the two pipes. Flow in a doublepipe heat exchanger can be cocurrent or. Design and analysis of a newly installed plate heat exchanger. It is the most common type of heat exchanger in oil refineries and other large chemical processes, and is suited for higherpressure applications. Detailed theoretical discussion on the principles of heat transfer was consciously left to readers to read standard textbook in heat transfer. The flow of water through the center tube can be reversed for either countercurrent or parallel flow. Usually, we need to figure out the required heat transfer area for a given job, given a flowrate. Design and analysis of a newly installed plate heat. Lectures 19 applied heat transfer cm3110 1232019 3 t, outer bulk temperature t, inner bulk temperature l but. Double pipe heat exchangers often also referred to as double pipes are characterized by a construction form which imparts a ushaped appearance to the heat exchanger. The wall of the inner pipe is the heat transfer surface.
Double pipe heat exchangers often also referred to as double. The entire analysis has been done by selecting an existing design of a double pipe heat exchanger with specified flow conditions at the inlet to the heat exchanger. Pdf design of double pipe heat exchanger kirti zare. Double pipe heat exchanger design with counterflow or. Key words double pipe heat exchangerheat transfer coefficientinner tube flowouter tube. A project report on implementation of traditional and non. The heat transfer by conduction mechanism that governs this system is the same as any heat exchanger.
The heat exchanger consists of two thin wall copper tubes mounted concentrically on a panel. Optimum design of double pipe heat exchanger sciencedirect. They have modelled the heat transfer from hot fluid to cold fluid using the cfd pa ckage phoenics 3. The two most common heat exchanger design problems are those of rating and sizing. Aug 26, 2002 the doublepipe heat exchanger is one of the simplest types of heat exchangers. Conclusion the design and analysis of the double pipe heat exchanger has been a great success. The analytical stage in this paper shows the validity of the. One of the medium flows inside of the smaller tube, while the other medium flows in the annulus. In this double pipe heat exchanger a hot process fluid flowing through the inner pipe transfers its heat to cooling water flowing in the outer pipe. Valves are used to set up desired flow conditions rate and direction. 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. 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. To understand the basic operation of heat exchangers. From the geyser outlet, the hot water is given as input to the inner pipe.
Many researchers have performed the design and analysis of double pipe heat exchanger. Convective heat transfer coefficient of the hotter side. Usually, we need to figure out the required heat transfer area for a given job, given a flowrate and a temperature difference. In contrast to the parallel flow heat exchanger, the counter flow heat exchanger can have the hottest coldfluid temperature greater than the coldest hotfluid temperatue. Keywords double pipe heat exchanger, fe 3 o 4 nano fluid, base fluid, over all heat transfer coefficient, effectiveness, nassult number, friction factor. Design and fabrication of double pipe heat exchanger using different heat transfer enhancement tecniques harsh ladani1, rajkamal sanepara2, mayur 4moradiya3, decent chopda, prof. Calculate the heat transfer area of the double pipe heat exchanger in the lab. The design of the exchanger has been formulated as a geometric programming with a single degree of difficulty. Design calculation result of double pipe heat exchanger b cfd analysis result of double pipe heat exchanger. So, we can supply the water either plain pipe heat exchanger or finned pipe heat exchanger.
The goals of this proje ct were to design a plate heat exchanger apparatus and evaluate the potential of replacing the current double pipe heat exchanger by this newly designed plate heat exchanger for the unit operation laboratory course. Crossflow just doesnt work for a double pipe heat exchanger. Double pipe heat exchanger design requires use of the heat transfer rate, the log mean temperature difference, and an estimate of the overall heat transfer coefficient to calculate the estimated heat transfer surface area. A composite system of alkaline fuel cells and peripheral. Heat exchanger types, diagram, working, applications.
The general operational characteristics of a counter current heat exchanger are outline in figure 2. A double pipe heat exchanger will typically be either counterflow or parallel flow. The hairpin heat exchanger design is similar to that of double pipe heat exchangers with multiple tubes inside one shell. The doublepipe heat exchanger is one of the simplest types of heat exchangers. Pdf design and construction of a double pipe heat exchanger. The design provides the flexibility of a utube design with an extended shell length that improves the exchanger s ability to achieve close temperature approaches. Effect of pressure hot on heat transfer surface area of hx. A double pipe heat exchanger is a system of two concentric pipes typically in the shape of a u, as shown in figures 1. Fluid engine oil sea water inlet temperature, c 65 20 outlet temperature, c 55 25 heat load, kw 117. Diagram of a single node for a double pipe heat exchanger.
Experimental investigation on heat transfer in double pipe heat. Mass flow rate heat transfer coefficient hot fluid outlet temperature cold fluid outlet temperature lpm k k 4 260. 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. May 01, 2008 although the necessary equations for heat transfer and the pressure drop in a double pipe heat exchanger are available, using these equations the optimization of the system cost is laborious. A double pipe heat exchanger is constructed from two pipes, one inside the other. An impressive list of information is available in relevant references for double pipe heat exchanger. Counter flow, double pipe heat exchanger dphe, longitudinal triangular fins. Horizontal double pipe heat exchanger uses various inserts inside tube so as to enhance heat transfer and hence increase heat transfer coefficient.
One of the most difficult aspects of heat exchange design is the reduction in heat transfer. Double pipe heat exchanger calculation does the thermal and hydraulic design of double pipe heat exchangers and estimate number of hairpin required. Double pipe heat exchanger dphx dphx design considerations pressure drop pipe or annulus should be less than 70 kpa. Specific heat capacity of air at constant pressure. The important parameters of heat exchangers are collected and put a major consideration on it. Overall heat transfer coefficient for doublepipe heat exchanger. Introduction double pipe heat exchangers are the simplest heat transfer devices. Optimized design parameters when heat transfer and compactness are prioritized35 table 54. This type of heat transfer mechanism is governed by the basic equation. Understanding heat exchangers types, designs, applications. In the present study, heat transfer from hot water to cold water by double pipe heat exchanger consists concentric tube is experimentally investigated. It can be operated as a parallel flow or as a counterflow heat exchanger.
Klm technology group process design of double pipe. Introduction a heat exchanger is a device that is used to transfer thermal energy enthalpy between two. The software will do all the thermal calculations involved in the design and will generate a summary of all resultsetc. Dhex is a software tool that is made to demonstrate the chemical design calculations of double pipe hairpin heat exchangers. A double pipe heat exchanger consists of two metal pipes, one inside the other as shown in figure 9. The double pipe heat exchanger is a small, modular design that is most useful in applications where conventional shell and tube exchangers are too large or too expensive to use. It is assumed that the flow rate, the inlet and the.
We certify that the project entitled design of small heat exchanger double pipe. A shell and tube heat exchanger is a class of heat exchanger designs. The heat exchanger is having inlet cold water from the above pipeline. The goals of this project were to design a plate heat exchanger apparatus and evaluate the potential of replacing the current double pipe heat exchanger by this.
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. Double pipe heat exchanger ce 328 spring 2003 objective. Introduction heat exchanger is a device which is used to transfer heat between two fluids which may be in direct contact or may flow separately in two tubes or channels. Double pile utube heat exchanger to study heat transfer. The hot water flows through the center tube, and cold water flows in the annular region. Design a double pipe heat exchanger with bare inner multitubes that can be used to cool engine oil with cold sea water. To design a heat exchanger, many criteria have to be taken before making any decision. Design of double pipe heat exchanger international. A double pipe heat exchanger consists of one pipe inside another. Cfd study of helically coiled double pipe heat exchangers for laminar flow situations were carried out by rennie and raghavan 2005, 2006a. Condensers which have a coolant and a condensing vapor brought into direct contact and other types which have the coolant and a condensate stream separated by a tube wall or a solid surface.
Unfortunately, this type of heat exchanger has a big disadvantage. When one of the fluids is hotter than the other, heat flows from it through the wall of the inner tube into the other fluid. U tube or hairpin heat exchanger can handle thermal expansion. In addition, the overall heat transfer equation for the exchanger must be solved simultaneously. This software deals with the type where the streams are separated when condensation occurs.
To determine the overall heat transfer coefficient for the double pipe heat exchanger for countercurrent flow and parallel or cocurrent flow. Usually, we need to figure out the required heat transfer area for a given job, given a. One fluid flows through the inner tube while the other fluid flows in the annular space between the pipe walls. 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. Fluid engine oil sea water inlet temperature, c 65 20 outlet temperature, c 55 25 heat. Heat exchanger design this chapter will provide the framework on how to design a double pipe and shell and tube type heat exchanger.
Double pipe exchangers can be paired in series or in parallel to increase the heat transfer. Condenser heat exchanger thermal analysis and design. Che 120b 1 heat exchangestheory the doublepipe heat. The inlet of hot water line is connected through shut off valve. A double pipe heat exchanger design and optimization for cooling. Base your calculation on the outside area of the inside pipe. In this paper the optimal design of the exchanger has been formulated as a geometric programming with a single degree of difficulty. To demonstrate the basic equations of heat exchanger operation.
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