A PROCEDURE FOR TUBE COUNT DETERMINATION IN SINGLE AND MULTIPLE PASS TUBULAR HEAT EXCHANGERS

The development of a simple computational procedure that allows the precise determination of important parameters for the thermal and mechanical design of tubular heat exchangers is discussed in the present work. The design of tubular heat exchangers for a wide variety of applications can involve the use of empirical expressions and data tables for the determination of the tube bundle parameters, such as the tube count and the tube bundle outside diameter. The motivation for developing the discussed procedure resides in addressing cases for which empirical expressions are inapplicable or data table are unavailable. Initially, the shell positions in which tubes can be placed are determined based on specified tube pitch, angle of arrangement, inlet and outlet nozzle diameters and tube bundle-to-shell clearance. The maximum number of tubes for the given configuration is obtained from the tube position searching procedure. A sorting algorithm, based on the tube distance to the shell center, is used to appropriately place a specified number of tubes within the heat exchanger cross section. Results for a single- and multiple-pass fixed-tubesheet heat exchangers are presented and compared with available tube count tables.

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A PROCEDURE FOR TUBE COUNT DETERMINATION IN SINGLE AND MULTIPLE PASS TUBULAR HEAT EXCHANGERS

Revista de Engenharia Térmica ◽

10.5380/ret.v4i2.5408 ◽

2005 ◽

Vol 4 (2) ◽

Author(s):

M. S. Medeiros ◽

A. J. K. Leiroz

Keyword(s):

Heat Exchangers ◽

Mechanical Design ◽

Tube Bundle ◽

Computational Procedure ◽

Precise Determination ◽

Sorting Algorithm ◽

Empirical Expressions ◽

Multiple Pass ◽

Data Tables

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Evaluation of resisdence time measurements on heat exchangers for the determination of dispersive Peclet numbers

Archives of Thermodynamics ◽

10.2478/aoter-2014-0016 ◽

2014 ◽

Vol 35 (2) ◽

pp. 103-115 ◽

Cited By ~ 5

Author(s):

Wilfried Roetzel ◽

Chakkrit Na Ranong

Keyword(s):

Heat Exchangers ◽

Evaluation Method ◽

Tube Bundle ◽

Dispersion Model ◽

Cascade Model ◽

Transfer Coefficients ◽

Heat Transfer Coefficients ◽

Measured Input ◽

Parabolic Dispersion

Abstract The recently developed special unity Mach number dispersion model prescribes the corrections to heat transfer coefficients which are simple functions of the dispersive Peclet numbers. They can be determined through the residence time measurements. An evaluation method is described in which the measured input and response concentration profiles are numerically Laplace transformed and evaluated in the frequency domain. A characteristic mean Peclet number is defined. The method is also applied to the parabolic dispersion model and the cascade model. A calculated example of a tube bundle with maldistribution and backflow demonstrates the suitability of the evaluation method.

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The latest mathematical and empirical models to calculate the thermal conductivity of the soils

E3S Web of Conferences ◽

10.1051/e3sconf/202132300007 ◽

2021 ◽

Vol 323 ◽

pp. 00007

Author(s):

Agnieszka Drzyzga

Keyword(s):

Thermal Conductivity ◽

Heat Exchangers ◽

Precise Determination ◽

Empirical Models ◽

Universal Model ◽

Ground Heat Exchangers ◽

New Models ◽

Underground Infrastructure

The paper presents the latest models for calculating the thermal conductivity of soil. Precise determination of this parameter is necessary for the correct and safe location of geoengineering objects, underground infrastructure such as cables or ground heat exchangers. A universal model that is easy to apply and gives the most accurate results has not yet been developed. New models are constantly being developed. The aim of this work is to present the latest models for calculating thermal conductivity, so that knowing the properties of the soil, it is possible to select an appropriate model to calculate its conductivity.

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Determination of creep mechanisms in various silicon carbides via TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143973 ◽

1986 ◽

Vol 44 ◽

pp. 484-487

Author(s):

C. H. Carter ◽

J. E. Lane ◽

J. Bentley ◽

R. F. Davis

Keyword(s):

Heat Exchangers ◽

Sintered Material ◽

Polycrystalline Material ◽

Chemical Vapor ◽

Graphite Substrate ◽

Second Phase ◽

Reaction Bonding ◽

Creep Mechanisms ◽

Porous Sic

Silicon carbide (SiC) is the generic name for a material which is produced and fabricated by a number of processing routes. One of the three SiC materials investigated at NCSU is Norton Company's NC-430, which is produced by reaction-bonding of Si vapor with a porous SiC host which also contains free C. The Si combines with the free C to form additional SiC and a second phase of free Si. Chemical vapor deposition (CVD) of CH3SiCI3 onto a graphite substrate was employed to produce the second SiC investigated. This process yielded a theoretically dense polycrystalline material with highly oriented grains. The third SiC was a pressureless sintered material (SOHIO Hexoloy) which contains B and excess C as sintering additives. These materials are candidates for applications such as components for gas turbine, adiabatic diesel and sterling engines, recouperators and heat exchangers.

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