Heat transfer 1 heat exchangers heat transfer heat exchanger types of heat exchangers heat exchangers are classified according to flow arrangement and. In multitubular or shell and tube heat exchangers, it is usual to combine. Examples of this type of heat exchanger are shell and tube exchangers, double tube exchangers and plate heat exchangers. In natural convection, fluid motion results from the hot atoms in the fluid, where the hot atoms move upwards toward. Additionally, heat exchangers may be classified according to the type of. But of the three, the counter flow heat exchanger design is the most efficient when comparing heat transfer rate per unit surface area. The engineer may have little knowledge of the attributes of these other types so is not able to make a reasonable.
For heat exchangers on applications which use polluted, shallow or brackish sea water as the coolant and have copper alloy tubes, it is recommended to run the heat exchanger in clean sea water for several weeks first, this creates a protective layer over the tube material which helps to protect against corrosion. Oct 11, 2019 different types of heat exchangers are used onboard a ship. A piece of equipment built for efficient heat transfer from one medium to another. Heat exchanger and its types engineering solutions. Heat exchangers are devices designed to transfer heat between two or more fluidsi. For the heat transfer to occur two fluids must be at different. The hot and cold fluids alternate between each of the plates. A compact heat exchanger is a device characterized by a high heat transfer area per unit volume more than 300 m2m3. A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another.
As the fluid or gas travels faster, the convective heat transfer increases. All these heat exchangers can be operated in both parallel and. Heat exchangers are classified according to transfer process number of fluids. Hcat exchangers usually provide a long service life with little or no maintenance because they do not contain any moving parts. A cooling tower comes under these types of heat exchangers. However, there are four types of heat exchanger failures that can occur, and can usually be prevented. The plateandframe heat exchanger design consists of stacked of corrugated plates which are bonded together. A heat exchanger is a piece of equipment built for efficient. R sekulib university of kentucky introduction a heat exchanger is a device that is used for transfer of thermal energy. The efficiency of a counter flow heat exchanger is due to the fact that the. Heat exchangers in sco 2 power cycles are critical components in sco 2 systems because of their size and cost. Three types of heat exchangers are generally required.
A shell and tube exchanger consists of a shell, tube bundle and two heads or caps at both ends of the shell. Heat exchangers are components that allow the transfer of heat from one fluid liquid or gas to another fluid. Heat exchangers are typically classified according to flow arrangement and type of construction. The devices that are used to facilitate heat transfer between two or more fluids at different temperatures are known as heat exchangers. Shell and tube heat exchangers are typically used for highpressure applications with pressures greater than 30 bar and temperatures greater than 260 degrees celsius. Such types of heat exchangers are used predominantly in air conditioning, humidification, industrial hot water heating, water cooling and condensing plants. Heat exchangers heat exchangers are one of the most common pieces of equipment found in all plants. Plate heat exchangers operate in very much the same way as a shell and tube heat exchanger, using a series of stacked plates rather than tubes. Additionally, heat exchangers may be classified according to the type of fluid used liquidtoliquid.
In these three types of flow the relative direction of hot and cold fluid. Jul 01, 2018 before study the type of heat exchangers we should have proper knowledge of the type of flow used in heat exchangers, because different types of flows are used in heat exchangers according to our requirement. Many types of heat exchangers have been developed for use in steam power plants, chemical processing plants, building heat and air conditioning systems, transportation power systems, and refrigeration units. Fixed tubesheet exchanger nonremovable tube bundle. Combining each of these resistances in series gives. In counter flow heat exchangers, the two fluids flow in. Heat exchangers have widespread industrial and domestic applications. Plate heat exchanger, how it works working principle hvac industrial engineering phx heat transfer duration. Each of the three types of heat exchangers has advantages and disadvantages. Depending on the type of heat exchanger employed, the heat transferring. The three most common types of shellandtube exchangers are fixed tubesheet design, utube design, and the floating head type. Exchangers the two main types of heat exchangers that exist.
Introduction to heat exchangers bengt sunden lund institute of technology. Almost all the systems onboard ship depends on heat exchanger where the fluid is either cooled or heated. Convection describes heat transfer between a surface and a liquid or gas in motion. Shell and tube heat exchangers are typically used for highpressure. The types of exchangers are mainly defined by their construction and are as follows. The type of heat exchanger used for a particular usage depends on the application and requirement. There are many types of heat exchangers applied in the process industry.
This article focuses on heat exchangers, exploring the various designs and types. On the other hand, according to their type of construction, exchangers are classified as. Two approaches to heat exchanger design that will be discussed are the lmtd method and the effec tiveness ntu method. Types of heat exchangers used on ship marine insight. A heat exchanger is a device that is used to transfer thermal energy enthalpy between. There are different types of compact heat exchanger design available. Heat exchangers are the devices which are used to exchange heat between two or more fluids which are at different temperature. Two types of convection are natural convection and forced convection. Heat exchangers 73 individual thermal resistances of the system.
In this case, the two fluids enter the heat exchanger from the same end with a large temperature difference. Types of heat exchangers classification of heat exchangers. Your heat exchanger should be used in accordance with the specified configuration of material, media types, temperatures and pressure for your specific heat exchanger 2. This heat exchanger consists of two concentric pipes of different diameters. Parallel flow heat exchanger in parallel flow heat exchangers, the two. They are widely used in space heating, refrigeration, air conditioning, power plants, chemical plants, petrochemical plants, petroleum refineries, natural gas processing and. Pdf a heat exchanger is a heat transfer device that exchanges heat between two or more process fluids. The simplest heat exchanger is one for which the hot and cold fluids move in the same or opposite directions. Unit operations lab heat exchanger 11 heat exchanger heat exchange is an important unit operation that contributes to efficiency and safety of many processes.
Heat exchanger is a process equipment designed for the effective transfer of heat energy between two fluids. Depending on the type of heat exchanger employed, the heat transferring process can be gastogas, liquidtogas, or liquidtoliquid and occur through a solid separator, which prevents mixing of the. Although the majority of heat exchangers used on chemical plant are shell and tube units, there are many other types available. Understanding heat exchangers types, designs, applications. The high efficiency and an outstanding reliability in a compact design, offers an investment with the most attractive cto over the product life time.
The engineer may have little knowledge of the attributes of. Gasketed plate heat exchangers can be flexibly adapted and, if necessary, extended to optimally meet our customers requirements. The shellandtube heat exchanger is composed of a shell containing a large number of tubes. But of the three, the counter flow heat exchanger design is the. As a result of this, heat and mass transfer takes place simultaneously. A heat exchanger is a device that is used to transfer thermal energy enthalpy. A shell and tube exchanger consists of a shell, tube bundle and. Heat exchangers that transfer heat from the heat source to the co 2 called primary or intermediate heat exchangers, or waste heat recovery whr heat exchangers. Types of heat exchanger, process design of shell and tube heat exchanger, condenser, and reboilers. In process calculations, the main objectives of heat exchanger calculations are to determine the heat. Pdf heat exchanger types and classifications researchgate. A heat exchanger is a heat transfer device that exchanges heat between two or more process fluids.
Pdf selection of heat exchanger types gerard hawkins. Additionally, heat exchangers may be classified according to the type of fluid. The actual design of heat exchangers is a complicated problem. This is particularly essential in the chemical, food and. Heat transfer heat exchanger types of heat exchangers. There are two inputs and two outputs, and the spaces between plates alternate between the two liquids hot, cold, hot, cold, etc. There is quite a large choice in types of heat exchangers.
A set of tubes is called the tube bundle and can be made up of several types of tubes. This type of heat exchanger consists of a set of tubes in a container called a shell. Plate and frame heat exchanger plate heat exchangers plate heat exchangers are constructed with a series of plates held together in a large frame. Cocurrent parallel flow heat exchangers in these types of heat exchangers, both the hot, as well as the cold fluids flow in the same. Comparison of heat exchanger types each of the three types of heat exchangers parallel, cross and counter flow has advantages and disadvantages. Doublepipe heat exchanger one fluid flows through the smaller pipe while the other fluid flows through the annular space between the two pipes. This allows the fluids at different temperatures to mix directly. Heat exchangers jordan university of science and technology.
Our gasketed plate heat exchangers are optimizing heat transfer by large surfaces of corrugated plates drawing heat from one gas or liquid to the other. Different types of shell and tube designs are possible. Introduction to heat exchangers bengt sunden lund institute of. These flows are parallel flow, counter flow and cross flow. The most basic and the most common type of heat exchanger construction is the shell and tube type. In parallel flow heat exchangers, both the tube side fluid and the shell side fluid flow in same direction. May 04, 2009 heat transfer 1 heat exchangers heat transfer heat exchanger types of heat exchangers heat exchangers are classified according to flow arrangement and type of construction.
Most direct contact heat exchangers fall under the gas liquid category, where heat is transferred between a gas and liquid in the form of drops, films or sprays. A plate type heat exchanger, as illustrated in figure 2, consists of plates instead of tubes to separate the hot and cold fluids. Types of heat exchangers shell and tube, plate type. Different types of heat exchangers are used onboard a ship. On the other hand, according to their type of construction. 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.
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