scholarly journals Importance of Shell & Tube Heat Exchangers In candy plants

2020 ◽  
Vol 5 (3) ◽  
pp. 15-18

Shell and Tube heat exchanger (HX) plays important role in candy plant. It transfers heat between two or more fluids. It is generally made of bundle of round tubes which are mounted in a cylindrical shell. And tubes are parallel to shell. We are covering several points such as why Shell and Tube heat exchangers are using in candy plants? Because there are many different types of Heat Exchangers are available in market. What are the major advantages that Shell and Tube heat exchangers are providing and others are not. What are limitations of other Heat Exchangers? And what are the main reasons behind use of Shell and Tube heat exchangers in candy plants?

Author(s):  
Majid Amidpour ◽  
Abazar Vahdat Azad

In this paper, the new approach of Constructal theory has been employed to design shell and tube heat exchangers. Constructal theory is a new method for optimal design in engineering applications. The purpose of this paper is optimization of shell and tube heat exchangers by reduction of total cost of the exchanger using the constructal theory. The total cost of the heat exchanger is the sum of operational costs and capital costs. The overall heat transfer coefficient of the shell and tube heat exchanger is increased by the use of constructal theory. Therefore, the capital cost required for making the heat transfer surface is reduced. Moreover, the operational energy costs involving pumping in order to overcome frictional pressure loss are minimized in this method. Genetic algorithm is used to optimize the objective function which is a mathematical model for the cost of the shell and tube heat exchanger and is based on constructal theory. The results of this research represent more than 50% reduction in costs of the heat exchanger.


2011 ◽  
Vol 134 (1) ◽  
Author(s):  
Natalia Petrova ◽  
Abdel-Hakim Bouzid

Despite the fact that multipass shell-and-tube heat exchangers operating at high temperature are subject to frequent problems related to flange sealing, there is neither detailed explanations for the reasons of the failures nor an adequate solution to this problem. Specific geometry of multipass heat exchangers and the temperature difference between the inlet and the outlet fluids is responsible for the existence of a thermal circumferential gradient at the shell-to-channel bolted joint. However, existing flange design methods do not address nonaxisymmetrical temperature loading of the flanged joint assembly. The circumferential thermal gradient, as the cause of frequent failures to seal the flanged joints, is ignored. This paper outlines the analytical modeling of a flanged joint with a tube sheet of a multipass heat exchanger subjected to a nonaxisymmetrical thermal loading. A shell-and-tube heat exchanger of 51 in. diameter with cocurrent flow was used for analysis. The main steps of the theoretical analysis used for the determination of the circumferential temperature profiles and the thermal expansion displacements and distortions of the bolted joint components are given. The results from the proposed analytical model are compared with those obtained from finite element models.


1994 ◽  
Vol 15 (3) ◽  
pp. 42-56 ◽  
Author(s):  
T. PEKDEMIR ◽  
T. W. DAVIES ◽  
L. E. HASELER ◽  
A. D. DIAPER

Author(s):  
Torsten Berning

This paper describes the development of a numerical algorithm and a graphical method that can be employed in order to determine the overall heat transfer coefficient inside heat exchangers. The method is based on an energy balance and utilizes the spreadsheet application software Microsoft Excel™. The application is demonstrated in an example for designing a single pass shell and tube heat exchanger that was developed in the Department of Materials Technology of the Norwegian University of Science and Technology (NTNU) where water vapor is superheated by a secondary oil cycle. This approach can be used to reduce the number of hardware iterations in heat exchanger design.


2020 ◽  
Vol 7 (2) ◽  
pp. F1-F7
Author(s):  
E. Nogueira

The objective of the work is to obtain the outlet temperatures of the fluids in a shell and tube heat exchanger. The second law of thermodynamics is applied through the concepts of efficiency, effectiveness, and irreversibility to analyze the results. Water flows in the shell, and a mixture of water-ethylene glycol is associated with fractions of nanoparticles flows in the tube. Water enters the shell at 27 °C, and the mixture comes to the tube at 90 °C. The mass flow is kept fixed in the shell, equal to 0.23 kg/s, and varies between 0.01 kg/s to 0.50 kg/s. Volume fractions equal to 0.01, 0.10, and 0.25 were considered for analysis, for both nanoparticles from Ag and Al2O3. Results for Reynolds number, heat transfer rate, efficiency, effectiveness, and irreversibility are presented for critique, discussion, and justification of the output data found. It is shown that the flow regime has a significant effect on the performance of the analyzed heat exchanger. Keywords: thermodynamics, second law, ethylene glycol, volume fraction.


2018 ◽  
Author(s):  
Javier Bonilla

Many commercial solar thermal power plants rely on indirect thermal storage systems in order to provide a stable and reliable power supply, where the working fluid is commonly thermal oil and the storage fluid is molten salt. The thermal oil - molten salt heat exchanger control strategies, to charge and discharge the thermal storage system, strongly affect the performance of the whole plant. Shell-and-tube heat exchangers are the most common type of heat exchangers used in these facilities. With the aim of developing advanced control strategies accurate and fast dynamic models of shell-and-tube heat exchangers are essential. For this reason, several shell-and-tube heat exchanger models with different degrees of complexity have been studied, analyzed and validated against experimental data from the CIEMAT-PSA molten salt test loop for thermal energy systems facility. Simulation results are compared in steady-state as well as transient predictions in order to determine the required complexity of the model to yield accurate results.


2003 ◽  
Vol 125 (3) ◽  
pp. 527-530 ◽  
Author(s):  
Ahmad Fakheri

This paper presents a single closed form algebraic equation for the determination of the Log Mean Temperature Difference correction factor F for shell and tube heat exchangers having N shell passes and 2M tube passes per shell. The equation and its graphical presentation generalize the traditional equations and charts used for the determination of F. The equation presented is also useful in design, analysis and optimization of multi shell and tube heat exchanger, particularly for direct determination of the number of shells.


Author(s):  
K. Mohammadi ◽  
W. Heidemann ◽  
H. Mu¨ller-Steinhagen

A semi-analytical model is presented for the evaluation of the performance factor of the inlet zone of an E type shell and tube heat exchanger without leakage flows. The performance factor is defined as the ratio of dimensionless heat transfer coefficients and pressure drops of both vertical and horizontal baffle orientation and therefore facilitates the decision between horizontal and vertical baffle orientation of shell and tube heat exchangers. The model allows the calculation of the performance factor of the inlet zone as a function of the baffle cut, the shell-side Reynolds number at the inlet nozzle and the Prandtl number of the shell-side fluid. The application of the model requires the knowledge of the performance factor of water at baffle cut equal to 24% of the shell inside diameter. For the development of the model a numerical data basis is used due to the lack of experimental data for shell and tube heat exchangers with different baffle orientations. The numerical data are obtained from CFD calculations for steady state conditions within a segmentally baffled shell and tube heat exchanger following the TEMA standards. Air, water and engine oil with Prandtl numbers in the range of 0.7 to 206 are used as shell-side fluids. The semi-analytical model introduced for the performance factor predicts the CFD results with a relative absolute error less than 5%. The presented model has to be validated with further experimental data and/or numerical results which explain the effect of baffle orientation on the shell-side heat transfer coefficient and pressure drop in order to check the general applicability.


2017 ◽  
Vol 67 (2) ◽  
pp. 13-24
Author(s):  
Štefan Gužela ◽  
František Dzianik ◽  
Martin Juriga ◽  
Juraj Kabát

AbstractNowadays, the operating nuclear reactors are able to utilise only 1 % of mined out uranium. An effective exploitation of uranium, even 60 %, is possible to achieve in so-called fast reactors. These reactors commercial operation is expected after the year 2035. Several design configurations of these reactors exist. Fast reactors rank among the so-called Generation IV reactors. Helium-cooled reactor, as a gas-cooled fast reactor, is one of them. Exchangers used to a heat transfer from a reactor active zone (i.e. heat exchangers) are an important part of fast reactors. This paper deals with the design calculation of U-tube heat exchanger (precisely 1-2 shell and tube heat exchanger with U-tubes): water – helium.


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