Fundamental Study on Multi-Layered Gas-to-Gas Heat Exchanger Using Porous Metal Plates as a Heat Transfer Medium : 2nd Report Fundamental Characteristics of Heat Exchanger without Porous Metal Plates

Pin fin heat exchanges are often used in cooling of high thermal loaded electronic components due to their excellent heat transfer performance. However, the pressure drop in such heat exchanges is usually much higher than that in others, so their overall heat transfer performance is seriously reduced. In order to reduce the pressure drop and improve the overall heat transfer performance for pin fin heat exchangers, porous metal pin arrays are used and the performance of fluid flow and heat transfer in heat exchanger unit cells are numerically studied. The Forchheimer-Brinkman extended Darcy model and two-equation heat transfer model for porous media are employed and the effects of Reynolds number (Re), permeability (K) and pin fin cross-section forms are studied in detail. The results show that, with proper selection of governing parameters, the overall heat transfer performance of porous pin fin heat exchanger is much better than that of traditional solid pin fin heat exchanger; the overall heat transfer performance of long elliptic porous pin fin heat exchanger is the best, that is, the heat transfer per unit pressure drop of such heat exchanger is the highest and the maximum value of the heat transfer over pressure drop is obtained at K = 2×10−7 m2.

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Fundamental study on the convective heat transfer augmentation of a wavy type heat exchanger.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.54.1428 ◽

1988 ◽

Vol 54 (502) ◽

pp. 1428-1433

Author(s):

Yasuo MORI ◽

Yutaka UCHIDA ◽

Hiroyoshi KOIZUMI

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Convective Heat Transfer ◽

Convective Heat ◽

Fundamental Study ◽

Heat Transfer Augmentation

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Investigation of the Degree of Augmentation of the Mass Transfer Coefficient of the Heat Transfer Medium in a Vortex Heat Exchanger of a Gas Pressure Regulating and Metering Station Heating System

Proceedings of Southwest State University ◽

10.21869/2223-1560-2021-25-1-53-65 ◽

2021 ◽

Vol 25 (1) ◽

pp. 53-65

Author(s):

N. P. Grigorova ◽

P. V. Monastyrev ◽

E. G. Pakhomova ◽

N. Ye. Semicheva

Keyword(s):

Heat Transfer ◽

Mass Transfer ◽

Heat Transfer Coefficient ◽

Heat Exchanger ◽

Natural Gas ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Gas Pressure ◽

Heat Transfer Medium ◽

The Heat Transfer Coefficient

Purpose of research. is to investigate the degree of augmentation of the mass transfer coefficient of a heat transfer medium in contact with a "spot" of liquid on the surface of the vortex blade when it is bombarded with dispersed contaminants in a vortex heat exchanger in order to identify a pattern that allows obtaining design values of the heat transfer coefficient of the heat transfer medium that have the best agreement with the experimental values provided in previously published articles [4, 6, 7].Methods. A complex analysis of the degree of augmentation of the mass transfer coefficient of the heat transfer medium on the surface of the vortex blade in a vortex heat exchanger based on the known theoretical positions and equations of heat and mass transfer processes.Results. The dependence of the augmentation of the mass transfer coefficient of the heat transfer medium in contact with the "spot" of liquid on the surface of the vortex blade when it is bombarded with dispersed contaminants was obtained, which allows obtaining the best agreement of the design and experimental values of the heat transfer coefficient in the vortex heat exchanger of a gas pressure regulating and metering station.Conclusion. The values of the heat transfer coefficient of the heat transfer medium calculated using the obtained dependence of the augmentation of the mass transfer coefficient of the heat transfer medium have a satisfactory convergence with the experimental data, which allows us to use this dependence in engineering calculations of the design parameters of the vortex heat exchanger used as a heat exchanger for the heating system of the working area of the gas pressure regulating and metering station. This technical solution allows not only saving natural gas as a source of heat generation, but also reducing the negative impact on the environment, since there is no need to burn natural gas. In this case, the production of thermal energy is carried out due to a regulated pressure drop of natural gas coming from the main line to consumers.

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Numerical and CFD Design of Heat Exchanger Used to Biomass Combustion

MATEC Web of Conferences ◽

10.1051/matecconf/202032802005 ◽

2020 ◽

Vol 328 ◽

pp. 02005

Author(s):

Marian Pafcuga ◽

Andrej Kapjor ◽

David Hecko ◽

Martin Vantuch

Keyword(s):

Heat Transfer ◽

Heat Transfer Coefficient ◽

Heat Exchanger ◽

Numerical Model ◽

Flue Gas ◽

Biomass Combustion ◽

Cfd Model ◽

Heat Transfer Medium ◽

The Heat Transfer Coefficient ◽

Tube Space

The article describes the design of a heat exchanger used for biomass combustion. The design takes into account simple maintenance of the exchanger, low input costs of construction and the highest possible efficiency. In the design is used the tubular type of heat exchanger. The construction consists of a tubular part - flue gas part, inter-tube space - heat transfer medium space. The output of the numerical model, CFD model is the heat transfer coefficient, heat exchanger power and final comparison of CFD and numerical model outputs.

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Experimental investigation and mathematical model of a heat exchanger with porous metal inserts

Tyumen State University Herald Physical and Mathematical Modeling Oil Gas Energy ◽

10.21684/2411-7978-2020-6-2-22-40 ◽

2020 ◽

Vol 6 (2) ◽

pp. 22-40

Author(s):

Boris G. Aksenov ◽

Oleg A. Stepanov ◽

Natalia V. Rydalina

Keyword(s):

Heat Transfer ◽

Mathematical Model ◽

Heat Exchanger ◽

Heat Exchangers ◽

Theoretical Data ◽

Porous Metal ◽

Porous Metals ◽

Standard Methods ◽

Porous Aluminum ◽

The Status

When creating and manufacturing heat exchangers, one of the main tasks is to increase the efficiency of heat transfer. The use of porous metals in heat exchangers is one of the promising ways to increase the heat transfer intensity, which determines the relevance of the study. The paper provides an overview of the status of this issue on literary sources. The purpose of the work is to conduct an experimental study of a heat exchanger with porous materials, to compile a mathematical model that allows analytical calculations of such heat exchangers, to confirm the correctness of the compiled model experimentally. An experimental bench has been created to study a heat exchanger that uses porous aluminum. The hot fluid is warm water that flows through pipes passing through a porous metal. The cold coolant flowing through the pores is freon, which cools the water. A schematic diagram and description of the stand are presented. A test cycle has been conducted. A comparison of the heat transfer intensity for materials of different porosity is given. Using standard methods for calculating heat exchangers in this case is not possible due to the lack of standard methods for determining the area of the inner surface with pores. In the course of the work, the standard equation describing the cooling of a porous body was proposed to be supplemented by the function of distributed heat sources. As a result, we have obtained a mathematical model of the heat exchanger under consideration in a simplified form, which can be used in technical calculations. The calculation results by the obtained method are correlated with the data of experiments. Deviations of empirical and theoretical data are within acceptable limits. The results obtained make it possible to use porous metals in order to increase the heat transfer intensity in the manufacture of heat exchangers. This technique allows calculations with an unknown heat exchange surface area, taking into account the heat capacity and heat of phase transition, if any. According to the methodology, the article is experimental-theoretical. Experiments are being conducted on the created laboratory bench. In parallel, calculations are made according to the developed mathematical model. The results are compared. Conclusions are made of a theoretical and applied nature.

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