Heat exchanger problem calculation lmtd and effectiveness. The shellandtube heat exchanger is composed of a shell containing a large number of tubes. Depending on the type of heat exchanger employed, the heat transferring. Simplified heat exchanger design calculations2 if inlet and outlet temperatures and one mass flow rate are known 1. A boiler is another heat exchanger in which one of the fluids absorbs heat and vaporizes. User needs of heat exchanger include types of fluids, quality. However, there is a disadvantage to smaller tubes if the fluid in your application is very viscous or has particulates, it can foul up the tube and undermine the heat transfer process. This portable document format \pdf\ file contains bookmarks, thumbnails, and hyperlinks to help you navigate through the document. Plate heat exchanger, how it works working principle hvac industrial engineering phx heat transfer duration. 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.
Doublepipe heat exchanger one fluid flows through the smaller pipe while the other fluid flows through the annular space between the two pipes. Different types of heat exchangers are shown in figure 42. This is composed of multiple, thin, slightlyseparated plates that have very large surface areas and fluid flow passages for heat transfer. Heat exchangers have widespread industrial and domestic applications. Heat exchangers jordan university of science and technology. Comparison of heat exchanger types each of the three types of heat exchangers parallel, cross and counter flow has advantages and disadvantages. These exchangers can be classified in many different ways. Finned tube heat exchanger or air cooled heat exchanger. Both recuperators and regenerators can be further separated into different categories of exchangers, such as. The fluids can be single or two phase and, depending on the exchanger type, may be separated or in direct contact. Classification based on flow arrangement based on flow arrangement heat exchangers are classified into the following principal types. Heat transfer equipments are found to be useful in a wide range of industries. Heat exchangers are used in both cooling and heating processes.
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, or between solid particulates and a fluid, at different temperatures and in thermal contact. Find out ntu from the ntu relationships for different types of heat exchangers 4. Due to the high heat transfer efficiency of the plates, plate type heat exchangers are usually very small when compared. A practical guide for planning, selecting and designing of shell and tube exchangers takes users on a stepbystep guide to the design of heat exchangers in daily practice, showing how to determine the effective driving temperature difference for heat transfer. Sensibleandlatent provides a model for a generic, sensible and latent airtoair heat exchanger that is an hvac air system component that consists of a heat exchanger and primarysecondary airflow bypass dampers. Heat exchangers can be classified according to flow arrangement and the construction features. Lewin heat exchanger design shellandtube heat exchangers these movies demonstrate the flow of process fluids in a typical shellandtube heat exchanger setup. Heat exchangers are devices that regulate efficient heat transfer from one fluid to another. Pdf selection of heat exchanger types gerard hawkins. Heat exchanger is an important and expensive item of equipment that is used almost in every industry oil and petrochemical, sugar, food, pharmaceutical and power industry.
Heat exchangers are devices that facilitate the exchange of heat between two fluids that are at different temperatures while keeping them from mixing with each other. Heat exchanger design using htri software simulation and optimization as well as thermal design using numerical analysis and calculations. A fourth type of heat exchanger uses an intermediate fluid or solid store to hold heat, which is then moved to the other side of the heat exchanger to be released. Heat exchangers study notes for mechanical engineering. Reason for heat exchangers a heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another hot and cold fluid. Heat exchangers and air conditioners are common elements in aec, data center, and other architectural applications, and play a significant role in their thermal management. The modules listed in the overview are linked to the corresponding pages. Plate heat exchanger another type of heat exchanger is the plate heat exchanger. Shell and tube heat exchanger design is a product developed by webbusterz engineering software.
All trademarks, registered trademarks, product names and company names or logos mentioned. Depending on the type of heat exchanger employed, the heat transferring process can be gastogas, liquidtogas, or liquidtoliquid and. The two most common kinds of heat exchanger are the shellandtube and platefin. Heat exchanger design handbook pdf alzaytoonah university.
Types of heat exchangersall heat exchangers do the same jobpassing heat from one fluid to anotherbut they work in many different ways. With a plate type heat exchanger, the heat penetrates the surface, which separates the hot medium from the cold one very easily. Almost all the systems onboard ship depends on heat exchanger where the fluid is either cooled or heated. In a single pass heat exchanger, the fluid goes into one end of a tube and out the other. But of the three, the counter flow heat exchanger design is the most efficient when comparing heat transfer rate per unit surface area. Proper simulation of both is essential for optimizing thermal behavior.
The exhaust air is filtered upstream of the heat exchanger, flows through the cross counterflow heat exchanger and is discharged to the outside by a fan. Heat exchanger modeling guidelines cfd autodesk knowledge. Heat transfer heat exchanger types of heat exchangers. John richard thome ltcm sgm epfl heat transfer heat exchanger design 1er mars 2008 4 41. The stack of heat transfer plates and gaskets is clamped together with bolts in a frame.
Although the majority of heat exchangers used on chemical plant are shell and tube units, there are many other types available. A heat exchanger is a heat transfer device that exchanges heat between two or more process fluids. Balanced counter flow heat exchanger assuming and cc, then the lmtd becomes undefined as. This heat exchanger consists of two concentric pipes of different diameters. Gasketed plate heat exchangers hxxxliquid gasketed plate heat exchangers are particularly suitable for large fl ows and high cooling capacities. The engineer may have little knowledge of the attributes of these other types so is not able to make a reasonable. A heat exchanger is a device designed to efficiently transfer or exchange heat from one matter to another between a solid object and a fluid, or between two or more fluids. Calculate q and the remaining mass flow rate using energy conservation 2. Heat exchanger types and selection in order to achieve optimum process operations, it is essential to use the right type of process equipment in any given process. Heat exchangers are major devices used in engineering field and have vast application in engineering processes like in refrigeration and air conditioning system, food processing system, powder plants, chemical reactors and aeronautical applications. The simplest heat exchanger is one for which the hot and cold fluids move in the same or opposite directions. Design considerations for shell and tube heat exchangers.
They can all be effective in a variety of heat transfer applications, but optimizing efficiency, cost, and space depend heavily on the particular process in which the heat exchanger is installed. A spiral heat exchanger is composed of two long, flat plates wrapped around a mandrel or center tube, creating two concentric spiral channels in a spiral heat exchanger, the hot fluid flows into the center of the unit and spirals outward toward the outer plates while at the same time, the cold fluid enters the periphery and spiral inward. As its name implies, this type of heat exchanger consists of a shell a large vessel. The shellandtube heat exchanger type has already been stud ied in walraven et. Different types of heat exchangers are used onboard a ship. The selection of a heat exchanger depends on many factors including capital and operating costs, fouling, corrosion tendency, pressure drop, temperature ranges, and safety issues tolerance to leakage. Plate heat exchanger applications general heating and cooling duties. Contents preface li acknowledgments liii author lv chapter1 heatexchangers. This site is not directly affiliated with webbusterz engineering software. This type of heat exchanger has a short thermal channel.
Dec 05, 20 a basic overview of common industrial heat exchangers including, shell and tube, plate and frame, brazed plate, welded plate and finned tube heat exchangers. A third type of heat exchanger uses an intermediate fluid or solid store to hold heat, which is then moved to the other side of the heat exchanger to be released. Gbhepeghea506 selection of heat exchanger types information contained in this publication or as otherwise supplied to users is believed to be accurate and correct at time of going to press, and is given in good faith, but it is for the user to satisfy itself of the suitability of the information for its. In parallel flow, both the hot and cold fluids enter the heat exchanger at the same end and move in the same direction, as shown in figure 1.
The types of exchangers are mainly defined by their construction and are as follows. Jul 01, 2016 heat can flow only from hotter to cooler fluids, as per the second law of thermodynamics. The heat absorbed by the matrix from the hot stream is transferred to the cold stream during its run. This is due to the larger area the plates provide over tubes. The tubes can also be straight, with one or two passes. The role of engineering designers is to convert the user needs into the heat exchanger outputs. Heat can flow only from hotter to cooler fluids, as per the second law of thermodynamics.
The heat exchanger must be isolated from system vibrations using flexible piping connections and isolation pads on the mounting feet. The type of heat exchanger used for a particular usage depends on the application and requirement. Other factors to consider when designing heat exchangers can include materials of construction, ease of maintenance, cost of the heat exchanger, and overall heat integration in. It is therefore possible to heat or cool fluids or gases which have minimal energy levels. Selection of heat exchanger types linkedin slideshare.
Types of heat exchangers industrial heat exchanger. Shell and tube heat exchanger design free download for. Plate heat exchangers can have many different types of corru gations 12. Heat exchangers are often given specific names to reflect the specific application for which they are used. Standard design the plate heat exchanger consists of a pack of corrugated metal plates with portholes for the passage of the two fluids between which heat transfer will take place. The transfer of heat takes place through the surface of the tubes. The first type of a heat exchanger is called the recuperative type, in which heat are exchanged on either side of a dividing wall by fluids. 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. The shell and tube heat exchanger in the photo above has about twelve times the efficiency than a hypothetical singletube heat exchanger of the same size. A heat exchanger is an equipment where heat energy is transferred from a hot fluid to a colder fluid. This stacked plate arrangement can be more effective, in a.
Pdf a heat exchanger is a heat transfer device that exchanges heat between two or more process fluids. Understanding heat exchangers types, designs, applications and. Lewin heat exchanger design shellandtube heat exchangers heuristic 55. Workable and optimum systems there are several types of heat exchanger connections used for domestic hot water dhw and space heating sh water generation in the substations 1. In process calculations, the main objectives of heat exchanger calculations are to determine the heat. Comparison of heat exchanger types parallel heat exchanger. Two types of flow arrangement are possible in a doublepipe heat exchanger.
The heat exchanger design and structure varies a lot depending on the application where they are used and the heat exchange media involved. For example, a condenser is a heat exchanger in which one of the fluids gives up heat and condenses as it flows through the heat exchanger. A better understanding of the basic principles of heat transfer and. They are widely used in space heating, refrigeration, air conditioning, power plants, chemical plants, petrochemical plants, petroleum refineries, natural gas processing and. Many types of heat exchangers have been developed for use in steam power plants. The cool outside air is also filtered in the ventilation system and subsequently absorbs the energy from the exhaust air in the cross counterflow heat exchanger and is supplied to the rooms by a second fan. Cross or counter flow as per their construction materials 1. Convection heat transfer is subdivided into two different kinds according to the nature of the flow. This means that the plate heat exchanger can also be dismantled for cleaning and maintenance. Different types of shell and tube designs are possible.
This type of heat exchanger, also referred to as a surface heat exchanger, can be. Their are many types of heat exchanger as per their flow arrangement 1. When a fluid is used to transfer heat, the fluid could be a liquid, such as water or oil, or could be moving air. User needs of heat exchanger include types of fluids, quality of fluids fouled fluids, clean fluids,etc.
Heat exchangers air system airtoair sensible and latent effectiveness heat exchanger overview. The following guidelines describe effective use of the heat exchanger material model. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. Three basic types of heat exchanger the simple parallel or counter. A heat exchanger follows this principle in its endeavour to reach equalization. Different types of heat exchangers in addition, the overall heat transfer equation for the exchanger must be solved simultaneously. The heat exchanger is an important component in every large industry. Types of heat exchanger basic of heat transfer introduction to heat exchanger. A piece of equipment built for efficient heat transfer from one medium to another. Types of heat exchangers used on ship marine insight. A sthe is the most common type of heat exchanger in oil re fineries and other large chemical processes, and is suited for higherpressure applications. If the heat exchanger is located at the inlet or discharge of a blower with a pulsating flow, such as a roots type rotary lobe blower, the heat exchanger must be protected from the pulsation by a chambered silencer. Examples are water cooling towers and jet condensers in. A heat exchanger is a system used to transfer heat between two or more fluids.
This is one of the common type of heat exchanger, a combination of shell and tube as shown in the figure, this shell and tube exchanger consists of a number of tubes mounted inside a cylindrical shell in which tubes runs parallel to shell. If the tube is curved, with the shape of a u, it is called a utube. A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. A closeup view of a section of a watertoair heat exchanger. Therefore a plate type heat exchanger, as compared to a similarly sized tube and shell heat exchanger, is capable of transferring much more heat. Heat exchanger calculation spreadsheet excel format. They are widely used in space heating, refrigeration, air conditioning, power stations, chemical plants. The air preheaters in steam power plants are usually quite different from the. Types of heat exchangers classification of heat exchangers.
Heat exchangers are devices designed to transfer heat between two or more fluidsi. Heat exchangers are typically classified according to flow arrangement and type of construction. Devices involving energy sources such as nuclear fuel pins or fired heaters are not normally regarded as heat exchangers although many of the principles. Pdf heat exchanger types and classifications researchgate. Two examples of this are adiabatic wheels, which consist of a large wheel with fine threads rotating. The transfer of heat energy between the two fluids could be carried out. When two plates of different pressing patterns are placed next to each other, the result is a compromise. Two examples of this are adiabatic wheels, which consist of a large wheel with fine threads rotating through the hot and cold fluids, and fluid heat exchangers. Oct 11, 2019 different types of heat exchangers are used onboard a ship. Heat convection refers to heat transfer that occurs between a surface and a moving fluid which are different temperatures. The plate pack is assembled between a fix frame plate and. Heat exchangers are the devices which are used to exchange heat between two or more fluids which are at different temperature. In shell and tube heat exchangers, one fluid flows through a set of metal tubes while the second fluid passes through a sealed shell that surrounds them. A finned tube heat exchanger, air cooled heat exchanger ache, cooler or dryer works by flowing a liquid into a series of tubes, whilst pumping gas or air around or over the pipework to cool the fluid down.
Heat transfer in heat exchangers involves convection in each fluid and conduction through the wall separating. 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 heat exchanger is a device used to transfer heat between two or more fluids. Heat exchanger and its types engineering solutions. It is through this technology that most of the industrial processes are successfully carried out. Two main types of heat exchangers the two main types of heat exchangers that exist. Heat exchangers can be classified into four types, according to.