scholarly journals Design, Performance, and Optimization of the Wire and Tube Heat Exchanger

2021 ◽  
Author(s):  
I Made Arsana ◽  
Ruri Agung Wahyuono
Keyword(s):  
Heat Exchanger ◽  
Heat Exchangers ◽  
Critical Role ◽  
Point Of View ◽  
Optimization Strategy ◽  
Or Efficiency ◽  
Tube Heat Exchanger ◽  
Future Design ◽  
Heat Exchanger Design ◽  
The Wire

The wire and tube heat exchanger has been mostly utilized as a condenser unit in various refrigeration systems. As a class of extended surface-based heat exchanger, not only the operating condition but also the geometry of the wire and tube heat exchanger plays a critical role in determining the overall performance of the heat exchanger. Despite the fact that the current designs that include the inline, single-staggered, and woven matrix-based wire and tube heat exchangers already exhibits positive performance, future design and optimization remain challenging from the thermal and fluids engineering point of view. To guide the optimization strategy in the heat exchanger design, this chapter provides an insight into how the geometrical design impacts the performance of various wire and tube heat exchangers, which can be deduced from either the heat exchanger capacity or efficiency.

Earth-Air and Earth-Water Heat Exchanger Design for Ventilation Systems in Buildings

2010 ◽  
Author(s):  
Michel De Paepe ◽  
Christophe T’Joen ◽  
Arnold Janssens ◽  
Marijke Steeman
Keyword(s):  
Heat Exchanger ◽  
Heat Exchangers ◽  
Design Methodology ◽  
Energy Use ◽  
Polyethylene Tube ◽  
Dynamic Simulations ◽  
Tube Heat Exchanger ◽  
Heat Exchanger Design ◽  
The Earth ◽  
Software Codes

Earth-air heat exchangers are often used for (pre)heating or (pre)cooling of ventilation air in low energy or passive house standard buildings. Several studies have been published in the passed about the performance of these earth-air heat exchangers [1–8]. Often this is done in relation to the building energy use. Several software codes are available with which the behaviour of the earth-air heat exchanger can be simulated. De Paepe and Janssens published a simplified design methodology for earth-air heat exchangers, based on thermal to hydraulic performance optimisation [7]. Through dynamic simulations and measurements it was shown that the methodology is quite conservative [9–10]. Hollmu¨ller added an earth-air heat exchanger model to TRNSYS [11]. In stead of using earth-air heat exchangers, earth-water heat exchangers are now getting more attention. In this system the ventilation air is indirectly cooled/heated with the water flow in a fin-tube heat exchanger in the inlet of the ventilation channel. The water-glycol mixture transfers heat with the earth by flowing through e.g. a polyethylene tube. In the second part of this paper a design methodology is first derived and then applied to this type of system.

A Numerical Algorithm and a Graphical Method to Size a Heat Exchanger

2011 ◽  
Author(s):  
Torsten Berning
Keyword(s):  
Heat Exchanger ◽  
Numerical Algorithm ◽  
Heat Exchangers ◽  
Graphical Method ◽  
Application Software ◽  
Microsoft Excel ◽  
Tube Heat Exchanger ◽  
Overall Heat Transfer Coefficient ◽  
Heat Exchanger Design ◽  
Shell And Tube

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.

Design and Optimization of Air-Cooled Heat Exchangers

1982 ◽  
Vol 104 (4) ◽  
pp. 683-690 ◽  
Author(s):  
C. P. Hedderich ◽  
M. D. Kelleher ◽  
G. N. Vanderplaats
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Pressure Drop ◽  
Heat Exchangers ◽  
Numerical Optimization ◽  
Tube Heat Exchanger ◽  
Design And Optimization ◽  
Heat Exchanger Design ◽  
Finned Tube Heat Exchanger ◽  
Augmented Lagrange Multiplier

A computer code has been developed for analysis of air-cooled heat exchangers and was coupled with a numerical optimization program to produce an automated air-cooled, heat-exchanger design and optimization procedure. A general iteration free approximation method was used for the analysis which calculates the mean overall heat-transfer coefficient and the overall pressure drop for many flow arrangements. The analysis takes into account the variation of the heat-transfer coefficients and the pressure drop with temperature and/or length of flow path. The code is not limited to surfaces found in the literature, but will accommodate any triangular pitch bank of finned tubes in multiple-pass configurations. The numerical optimization code is a general purpose program based on the Method of Feasible Directions and the Augmented Lagrange Multiplier Method. The capability is demonstrated by the design of an air-to-water finned-tube heat exchanger and is shown to be a useful tool for heat exchanger design.

Air-Side Thermal and Drain Performance of Wire-Strip Fin-Tube Heat Exchanger

2012 ◽  
Author(s):  
Hie Chan Kang ◽  
Sun An Jeong
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Transfer Rate ◽  
Empirical Correlations ◽  
Tube Heat Exchanger ◽  
Theoretical Predictions ◽  
The Wire ◽  
Fin Tube ◽  
Strip Heat

The purpose of the present study is to investigate the characteristics of pressure drop, heat transfer rate and drainability of a wire-strip heat exchanger modified from the conventional louver fin one. Scaled-up models with the standard and four kinds of wire-strip fins were made, and their thermal and hydraulic performances tested in a wind tunnel. The drainability of the fins was evaluated by measuring the water retained after dipping the heat exchangers. The f and j factors and their ratios for the wire-strip fins are compared with those of the conventional louver fin, and empirical correlations and theoretical predictions were made. The best design for the wire-strip fins showed a better thermal performance per unit fan power than the standard louver fin by several tens of percent. It also retained about half or less of the water.

Optimization and Standardization of Flanged and Flued Expansion Joint Design

2019 ◽  
Vol 141 (3) ◽  
Author(s):  
Kamlesh M. Chikhaliya ◽  
Bhaveshkumar P. Patel
Keyword(s):  
Heat Exchanger ◽  
Optimum Design ◽  
Design Methodology ◽  
Thick Wall ◽  
Process Conditions ◽  
Expansion Joint ◽  
Standard Requirement ◽  
Spring Rate ◽  
Tube Heat Exchanger ◽  
Heat Exchanger Design

Flanged and flued type expansion joint (thick wall expansion bellow) used as an integral part of many shell and tube heat exchanger where process conditions produce differential expansion between shell and tubes. It provides flexibility for thermal expansion and also functions as a pressure retaining part. Design of expansion joints is usually based on trial and error method in which initial geometry must be assumed, and accordingly maximum stresses and spring rate are be calculated. Inadequate selection of geometry leads to higher tubesheet and bellow thickness, which increases cost of equipment. This paper presents standardization and optimum design approach of flange and flued expansion bellow fulfilling ASME VIII-1 and TEMA standard requirement. Methodology to define expansion bellow geometry is developed, and geometry dimensions are tabulated for expansion bellow diameter from 300 to 2000 mm and thickness from 6 to 30 mm. Each defined geometry is analyzed using finite element method, and maximum von Mises stresses are calculated for bellow axial displacement from 0.5 to 1.5 mm and internal pressure from 0.1 to 6.5 MPa. Spring rate is also calculated for each defined geometry for consideration in tubesheet calculation. Accordingly, optimum design methodology is developed, tested, and compared with existing design. Results depicted that proposed standardization approach and design methodology will optimize expansion bellow and tubesheet thickness and will also save considerable time in finalization of heat exchanger design.

Analysis of the Thermal Stress at the Tubesheet in Floating-Head or U-Tube Heat Exchangers

2017 ◽  
Vol 139 (2) ◽  
Author(s):  
Jiuyi Liu ◽  
Caifu Qian ◽  
Huifang Li
Keyword(s):  
Thermal Stress ◽  
Heat Exchanger ◽  
Temperature Difference ◽  
Heat Exchangers ◽  
Influence Factors ◽  
Area Ratio ◽  
Shell Side ◽  
Tube Heat Exchanger ◽  
Numerical Tests ◽  
Hole Area

Thermal stress is an important factor influencing the strength of a heat exchanger tubesheet. Some studies have indicated that, even in floating-head or U-tube heat exchangers, the thermal stress at the tubesheet is significant in magnitude. For exploring the value, distribution, and the influence factors of the thermal stress at the tubesheet of these kind heat exchangers, a tubesheet and triangle arranged tubes with the tube diameter of 25 mm were numerically analyzed. Specifically, the thermal stress at the tubesheet center is concentrated and analyzed with changing different parameters of the tubesheet, such as the temperature difference between tube-side and shell-side fluids, tubesheet diameter, thickness, and the tube-hole area ratio. It is found that the thermal stress of the tubesheet of floating-head or U-tube heat exchanger was comparable in magnitude with that produced by pressures, and the distribution of the thermal stress depends on the tube-hole area and the temperature inside the tubes. The thermal stress at the center of the tubesheet surface is high when tube-hole area ratio is very low. And with increasing the tube-hole area ratio, the stress first decreases rapidly and then increases linearly. A formula was numerically fitted for calculating the thermal stress at the tubesheet surface center which may be useful for the strength design of the tubesheet of floating-head or U-tube heat exchangers when considering the thermal stress. Numerical tests show that the fitted formula can meet the accuracy requirements for engineering applications.

scholarly journals Performance analyses of helical coil heat exchangers. The effect of external coil surface modification on heat exchanger effectiveness

2016 ◽  
Vol 37 (4) ◽  
pp. 137-159 ◽  
Author(s):  
Rafał Andrzejczyk ◽  
Tomasz Muszyński
Keyword(s):  
Heat Transfer ◽  
Surface Modification ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Helical Structure ◽  
Nuclear Industry ◽  
Helical Coil ◽  
Tube Heat Exchanger ◽  
High Heat Transfer ◽  
Coil Heat

Abstract The shell and coil heat exchangers are commonly used in heating, ventilation, nuclear industry, process plant, heat recovery and air conditioning systems. This type of recuperators benefits from simple construction, the low value of pressure drops and high heat transfer. In helical coil, centrifugal force is acting on the moving fluid due to the curvature of the tube results in the development. It has been long recognized that the heat transfer in the helical tube is much better than in the straight ones because of the occurrence of secondary flow in planes normal to the main flow inside the helical structure. Helical tubes show good performance in heat transfer enhancement, while the uniform curvature of spiral structure is inconvenient in pipe installation in heat exchangers. Authors have presented their own construction of shell and tube heat exchanger with intensified heat transfer. The purpose of this article is to assess the influence of the surface modification over the performance coefficient and effectiveness. The experiments have been performed for the steady-state heat transfer. Experimental data points were gathered for both laminar and turbulent flow, both for co current- and countercurrent flow arrangement. To find optimal heat transfer intensification on the shell-side authors applied the number of transfer units analysis.

Basis of the Tubesheet Heat Exchanger Design Rules Used in the French Pressure Vessel Code

1992 ◽  
Vol 114 (1) ◽  
pp. 124-131 ◽  
Author(s):  
F. Osweiller
Keyword(s):  
Heat Exchanger ◽  
Pressure Vessel ◽  
Heat Exchangers ◽  
Tube Bundle ◽  
Outer Edge ◽  
Design Rules ◽  
Effective Elastic Constants ◽  
Heat Exchanger Design ◽  
Solid Plate ◽  
Main Basis

For about 40 years most tubesheet exchangers have been designed according to the standards of TEMA. Partly due to their simplicity, these rules do not assure a safe heat-exchanger design in all cases. This is the main reason why new tubesheet design rules were developed in 1981 in France for the French pressure vessel code CODAP. For fixed tubesheet heat exchangers, the new rules account for the “elastic rotational restraint” of the shell and channel at the outer edge of the tubesheet, as proposed in 1959 by Galletly. For floating-head and U-tube heat exchangers, the approach developed by Gardner in 1969 was selected with some modifications. In both cases, the tubesheet is replaced by an equivalent solid plate with adequate effective elastic constants, and the tube bundle is simulated by an elastic foundation. The elastic restraint at the edge of the tubesheet due the shell and channel is accounted for in different ways in the two types of heat exchangers. The purpose of the paper is to present the main basis of these rules and to compare them to TEMA rules.

A Heuristic for Designing Hybrid Compact Heat Exchangers for Nuclear Applications

2021 ◽  
Author(s):  
Venkata Rajesh Saranam ◽  
Peter Carter ◽  
Kyle Rozman ◽  
Ömer Dogan ◽  
Brian K. Paul
Keyword(s):  
Heat Exchanger ◽  
Diffusion Bonding ◽  
Heat Exchangers ◽  
Nuclear Power ◽  
Nuclear Industry ◽  
Compact Heat Exchangers ◽  
Bonding Parameters ◽  
Heat Exchanger Design ◽  
Creep Fatigue ◽  
Gen Iv

Abstract Hybrid compact heat exchangers (HCHEs) are a potential source of innovation for intermediate heat exchangers in nuclear industry, with HCHEs being designed for Gen-IV nuclear power applications. Compact heat exchangers are commonly fabricated using diffusion bonding, which can provide challenges for HCHEs due to resultant non-uniform stress distributions across hybrid structures during bonding, leading to variations in joint properties that can compromise performance and safety. In this paper, we introduce and evaluate a heuristic for determining whether a feasible set of diffusion bonding conditions exist for producing HCHE designs capable of meeting regulatory requirements under nuclear boiler and pressure vessel codes. A diffusion bonding model for predicting pore elimination and structural analyses are used to inform the heuristic and a heat exchanger design for 316 stainless steel is used to evaluate the efficacy of the heuristic to develop acceptable diffusion bonding parameters. A set of diffusion bonding conditions were identified and validated experimentally by producing various test coupons for evaluating bond strength, ductility, porosity, grain size, creep rupture, creep fatigue and channel deviation. A five-layer hybrid compact heat exchanger structure was fabricated and tensile tested demonstrating that the bonding parameters satisfy all criteria in this paper for diffusion bonding HCHEs with application to the nuclear industry.

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