Design methods2 shell and tube heat exchangers are designed normally by using either kerns method or belldelaware method. Design and fabrication of shell and tube heat exchanger. Of design following the kern method are summarized as follows. It is the most common type of heat exchanger in oil reneries and other large chemical processes, and it is. Heat exchanger design is a very important problem in industries. To eliminate design problems, computer software dsthe software has been developed. The two most common heat exchanger design problems are those of rating and sizing. Shell and tube heat exchanger most commonly used type heat transfer equipment in chemical and allied industries advantages. Pdf a compact formulation of the belldelaware method. Step cess as well as it also provides an idea about various equipment used for heat transfer. Another approach introduce the definition of heat exchanger effectiveness, which is a dimensionless with ranging between 0 to1. A compact formulation of the belldelaware method for heat exchanger design and optimization article pdf available in chemical engineering research and design 835.
Kern developed a relationship applicable to any heat exchanger with an even number of passes and generated temperature correction factor plots. Kerns method for tube and shell heat exchanger design. Pdf handout that help students for design of heat exchangers based on kerns method find, read and cite all the research you need on. Whereas, the belldelaware method is more accurate method and can provide detailed results. How to design shell and tube heat exchanger in excel spreadsheet. One of these methods is the wellknown kern method, which was an attempt to correlate data. Design of shell tube heat exchanger by kern method 2 57 excel. This is a proven method used in design of heat exchangers with a baffle cut of 25%. The term heat exchanger applies to all equipment used to transfer heat between two streams. Contents shell and tube heat exchanger applications different design methods. This chapter discusses the basic design methods for two fluid heat exchangers. Pdf design of shell and tube heat exchanger single. The kern method is discussed here to calculate the individual heat transfer coefficient.
The design of shell and tube heat exchangers is very compact. An attempt is made in this paper is design of shell and tube double pass heat exchanger with helical baffle and comparing with segmental baffle using kern method. The kerns method is used to size both heat exchangers. The design of shell and tube heat exchanger using kern method for water and steam combination is validated by wellknown dittusboelter equation of turbulent flow inside tube. Both heat exchangers has a large heat duty and both are designed as single shell pass and two tube pass heat exchanger. Design of shell tube heat exchanger by kern method 2 57 excel template free download as excel spreadsheet. Method of heat exchanger sizing kern method free download as excel spreadsheet.
Heat exchanger design free download as powerpoint presentation. Design methods2 shell and tube heat exchangers are designed normally by using either kern s method or belldelaware method. That is, the design of a two fluid heat exchanger used for the purposes of. The design work has been done considering the desired capacity of the plant, which is 100 tonsday of nitric acid. Giving reasonably satisfactory prediction of the heattransfer coefficient for standard design simple to apply accurate enough for preliminary design calculations accurate enough for designs when uncertainty in other design parameter is. We discuss the logmean temperature difference lmtd method, the effectiveness.
This method requires the film to be in streamline flow with a reynolds numbers range 1800 to 2100. Giving reasonably satisfactory prediction of the heat transfer coefficient for standard design simple to apply accurate enough for preliminary design calculations accurate enough for designs when uncertainty in other design parameter is. Kern s method bases on experimental data which can lead to reasonable prediction for nusselt number 4. However, the term is commonly used to equipment in which two process streams exchange heat with each other. Introduction a shell and tube heat exchanger is a class of heat exchanger designs. Chemcad is used to establish the steady state mass and energy balances across the heat exchanger and typical values of the ohtc are shown in the attachments. The used procedure to design the heat exchanger in this paper is kern s method. Kern adapted the nusselt equation to allow evaluation of fluid conditions at the film temperature. In our case, the heat exchanger will be made with using the kern method. Design of shell tube heat exchanger by kern method 2. The analysis is extended using the above kern method with different fluid. The heat transfer analysis is done by considering water inside the tube and steam on shell side.
Since delaware method is a rating analysis, first kern method is used to estimate the size of the heat exchanger for a given specification. Optimal shell and tube heat exchangers design 5 bwg din m. The correction factor f t for a 12 heat exchanger which has 1 shell pass and 2 or more even number of tube. E1mnl032a design and rating of shell and tube heat. Handout that help students for design of heat exchangers based on kern s method. Pdf process heat transfer by donald kern free download.
Two approaches to heat exchanger design that will be discussed are the lmtd method and the effec. Design of heat exchanger for efficient quenching process. Two different methods, kerns method and bells method, have been used for the design. Sep 09, 2015 5 introduction to kerns method kerns was based on experimental work on commercial exchanger advantages. If the heat transfer coefficients at the tube side and the shell side are known, the overall heat transfer coefficient u. Ravagnani and caballero 2007a model formulation the model for the design of the optimum she ll and tube equipment considers the objective function as the minimum cost including exchange area cost and pumping cost, rigorously. Kerns method is mostly used for the preliminary design and provides conservative results whereas, the belldelaware method is more accurate method and can provide detailed results. Ntu method, dimensionless mean temperature difference.
The kern method kern adapted the nusselt equation to allow evaluation of fluid conditions at the film temperature. All design parameters have been calculated by this method with the help of dsthe software such as number of tubes, shell diameter, pipe pitch and pitch ratio. This method requires the film to be in streamline flow with a. Design of shell and tube heat exchanger, htri software, kern method and bell delaware method kern method and belldelaware method prof. Tech 1 pg scholar, department of thermal, mlr institute of technology, ranga reddy, telangana, india.
In this paper we have designed a simple counter flow shell and spiral tube type heat. The paper also consists of the thermal analysis of a helixchanger continuous helical baffled heat exchanger using the kern method, modified to estimate the results for different flow rates at a fixed helical angle of 25. It can predict heat transfer coefficient with better accuracy. The used procedure to design the heat exchanger in this paper is kerns method. Design of shell and tube type heat exchanger using cfd tools. Abstractin this research work, shell and tubetype heat exchanger has been designed by kern method. It is based on mechanical shell side details and presents more realistic and accurate results for the shell side film heat transfer coefficient and pressure drop.
Shell and tube heat exchanger design is normally based on correlations, among these, the kern method and belldelaware method are the most commonly used correlations. Pdf a compact formulation of the belldelaware method for. Various types of fins and attachments are illustrated in fig. Design of heat exchanger for efficient quenching process of. Nov 30, 2015 the heat exchanger layout depends on the heat transfer area hta so an initial estimate is required based on a trial value of the ohtc. The lmtd method can be used if inlet temperatures, one of the fluid. We use an eshell type and the service must be executed in a single shell without loss of generality. Designing shell andtube heat exchangers using softwares lecture 1. While, the pressure drop prediction is less satisfy because it is affected by leakage and bypassing than heat transfer 4. Shell and tube heat exchanger is designed by trial and error calculations. Pdf design of shell and tube heat exchanger single phase.
Handout that help students for design of heat exchangers based on kerns method. The flow regime considered is a turbulent one, as it is common in industrial equipment. Kerns method is mostly used for the preliminary design and provides conservative results whereas. Heat exchanger design fundamental equation youtube.
Thermal design models synopsis ii cctherm user guidelines iii thermal model selection iv shortcut heat exchanger design v tema heat exchanger layout designation vi typical overall heat transfer coefficients vii typical resistance fouling coefficients viii lmtd correction factor ft ix wolverine. Moreover the constructional details and design methods of shell and tube type heat exchangers has been given from which of that the kern method for design is. The shellside pressure drop obtained by belldelaware method is about 48% lower than that obtained by the kern method. Kerns method bases on experimental data which can lead to reasonable prediction for nusselt number 4. A heat exchanger may be defined as equipment which transfers the energy from a hot fluid to a cold fluid, with. In this work, the design of a counter current shell and tube heat exchanger used in nitric acid plants has been presented. The basic layout for a countercurrent shell and tube heat exchanger together with the associated heat curve for a condensing process generated from chemcad are shown. Kern method is mostly used for the preliminary design and provides conservative results. Assume tube diameter and bwg, assume tube length, l 2.
Designing shellandtube heat exchangers using softwares. Plate heat exchanger, how it works working principle hvac industrial engineering phx heat transfer duration. Design of shell tube heat exchanger by kern method 2 57. 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 exchanger effectiveness ntu method if more than one of the inlet and outlet temperature of the heat exchanger is unknown, lmtd may be obtained by trial and errors solution. Figure 2 presents the method fl ow model, that considers different streams. Since heat duty is comparatively very large, the heat exchanger is designed as a two heat exchanger unit arranged in a series. The main steps of design following the kern method are summarized as follows. Plate type heat exchanger design linkedin slideshare. Calculation of individual heat transfer coefficient of the boiling liquid. Schematic diagram of component of shell and tube type heat exchanger iii. Analysis study of shell and tube heat exchanger for clough. Heat exchangers jordan university of science and technology. 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.
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