CFD Analysis of Melting Process in Pipelines for Wax Removal by Hot Water

Abstract This paper focuses on the numerical study of the melting process of the wax when using the “stuffy pipeline” operation to remove the wax. Transient two dimensional heat transfer analysis was performed by using the enthalpy-porosity and Volume of Fluid (VOF) methods in ANSYS FLUENT. This study aimed at revealing the phase change heat transfer characteristics of wax melting process. The effects of water temperature, the thickness of the wax layer and wax layer composition on the melting process were investigated. The results show that when the “stuffy pipeline” operation is adopted, the operation time should be controlled wisely, the effect of wax removal does not increase over time. Moreover, the thickness of the wax layer is smaller, and the effect of wax removal is greatly reduced. The composition of wax layer has a significant influence on the melting process. When the wax is distributed in a single or double layer, the liquid contours of wax varies greatly.

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A Numerical Study for a Double Twisted Tube Heat Exchanger

International Journal of Heat and Technology ◽

10.18280/ijht.390521 ◽

2021 ◽

Vol 39 (5) ◽

pp. 1583-1589

Author(s):

Ali K. Abdul Razzaq ◽

Khudheyer S. Mushatet

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Numerical Study ◽

Hot Water ◽

Flow Mode ◽

Outer Diameter ◽

Outlet Temperature ◽

Ansys Fluent ◽

Tube Heat Exchanger ◽

Twisted Tube

The thermal and fluid physiognomies of a double twisted tube heat exchanger was examined numerically. Twisted engineering is a wide-use method to improve heat transfer in heat exchangers. A counter-flow mode utilizing hot water in the inner tube and cold air in the outer tube was considered. This study aims to progress the thermal performance of the double tube heat exchanger by using twisted tubes instead of plane tubes. The heat exchanger was (1m) length, outer diameter (0.05m) and inner diameter (0.025m), both with a thickness (0.004m). It was tested for different values of twist ratios (Tr= 5, 10, and 15 respectively) and Reynolds numbers (Re=5000 to 30000). The Navier - Stockes and energy equations besides the turbulence model in demand for modelling this physical problem. ANSYS Fluent code was used for the numerical simulation. The results showed that the twisted tube heat exchanger showed increasing heat transfer compared with a plain tube heat exchanger. It was found that the cold outlet temperature, pressure drop and effectiveness are increased as the twist ratio increases.

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Heat transfer analysis of double tube heat exchanger with wavy inner tube

Thermal Science ◽

10.2298/tsci210628266h ◽

2021 ◽

pp. 266-266

Author(s):

Ceren Hasgül ◽

Gülşah Çakmak

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Numerical Study ◽

Three Dimensional ◽

Heat Transfer Analysis ◽

Wave Number ◽

Straight Tube ◽

Flow Conditions ◽

Ansys Fluent ◽

Tube Heat Exchanger

In this study, the effect of the design on the heat transfer is numerically investigated by using the "wavy inner tube" in a double-pipe heat exchanger. A wavy inner tube was used in the design to give a turbulent effect to the fluid along the inner tube of a double tube heat exchanger. In numerical study, ANSYS 12.0 Fluent code program was used, and the basic protection equations were solved for steady-state, three-dimensional and turbulent flow conditions. The study was examined at Reynolds numbers ranging from 2700 to 5300. The obtained results were compared with the experimental data performed under the same conditions. As a result of this comparison, after it was seen that the results obtained from the numerical analysis and the experimental results were compatible with each other, the wave number of the inner tube was increased and analyzed with the ANSYS fluent code program. When the data obtained as a result of the analyzes were evaluated, it was seen that the highest heat transfer was obtained from the 16 wave tube heat exchanger, which has the highest number of waves and under counter flow conditions. The increase in heat transfer increased by 270% compared to the straight tube.

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An Investigation of the Effect of interrupted fin arrangements on the Thermal Performance of a Heat Sink under a Free Convection Condition

Wasit Journal of Engineering Sciences ◽

10.31185/ejuow.vol7.iss1.113 ◽

2019 ◽

Vol 7 (1) ◽

pp. 43-53

Author(s):

Abbas Jassem Jubear ◽

Ali Hameed Abd

Keyword(s):

Heat Transfer ◽

Steady State ◽

Natural Convection ◽

Thermal Performance ◽

Heat Sink ◽

Numerical Study ◽

Ansys Fluent ◽

Fluent Software ◽

Steady State Heat ◽

Steady State Heat Transfer

The heat sink with vertically rectangular interrupted fins was investigated numerically in a natural convection field, with steady-state heat transfer. A numerical study has been conducted using ANSYS Fluent software (R16.1) in order to develop a 3-D numerical model. The dimensions of the fins are (305 mm length, 100 mm width, 17 mm height, and 9.5 mm space between fins. The number of fins used on the surface is eight. In this study, the heat input was used as follows: 20, 40, 60, 80, 100, and 120 watts. This study focused on interrupted rectangular fins with a different arrangement and angle of the fins. Results show that the addition of interruption in fins in various arrangements will improve the thermal performance of the heat sink, and through the results, a better interruption rate as an equation can be obtained.

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A Numerical Study of MHD and Heat Transfer Analysis in a non-Newtonian Eyring-Powell Fluid from an Isothermal Sphere with Thermal Slip

Indian Journal of Science and Technology ◽

10.17485/ijst/2017/v10i17/104598 ◽

2017 ◽

Vol 10 (17) ◽

pp. 1-5

Author(s):

K. Madhavi ◽

N. Nagendra ◽

V. Ramachandra Prasad ◽

A. Subba Rao ◽

G. S. S. Raju ◽

...

Keyword(s):

Heat Transfer ◽

Numerical Study ◽

Heat Transfer Analysis ◽

Thermal Slip

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Numerical Simulation of Secondary Flow in Gas Turbine Disc Cavities, Including Conjugate Heat Transfer

Volume 1: Turbomachinery ◽

10.1115/96-gt-067 ◽

1996 ◽

Cited By ~ 7

Author(s):

Y.-H. Ho ◽

M. M. Athavale ◽

J. M. Forry ◽

R. C. Hendricks ◽

B. M. Steinetz

Keyword(s):

Heat Transfer ◽

Secondary Flow ◽

Conjugate Heat Transfer ◽

Gas Flow ◽

Numerical Study ◽

Labyrinth Seal ◽

Temperature Fields ◽

Heat Transfer Analysis ◽

Flow Rates ◽

Turbine Disc

A numerical study of the flow and heat transfer in secondary flow elements of the entire inner portion of the turbine section of the Allison T-56/501D engine is presented. The flow simulation included the interstage cavities, rim seals and associated main path flows, while the energy equation also included the solid parts of the turbine disc, rotor supports, and stator supports. Solutions of the energy equations in these problems usually face the difficulty in specifications of wall thermal boundary conditions. By solving the entire turbine section this difficulty is thus removed, and realistic thermal conditions are realized on all internal walls. The simulation was performed using SCISEAL, an advanced 2D/3D CFD code for predictions of fluid flows and forces in turbomachinery seals and secondary flow elements. The mass flow rates and gas temperatures at various seal locations were compared with the design data from Allison. Computed gas flow rates and temperatures in the rim and labyrinth seal show a fair 10 good comparison with the design calculations. The conjugate heat transfer analysis indicates temperature gradients in the stationary intercavity walls, as well as the rotating turbine discs. The thermal strains in the stationary wall may lead to altered interstage labyrinth seal clearances and affect the disc cavity flows. The temperature, fields in the turbine discs also may lead to distortions that can alter the rim seal clearances. Such details of the flow and temperature fields are important in designs of the turbine sections to account for possible thermal distortions and their effects on the performance. The simulation shows that the present day CFD codes can provide the means to understand the complex flow field and thereby aid the design process.

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Numerical Study of the Effect of the Location of Baffles on the Flow and Heat Transfer of A Newtonian Fluid in A Ventilated Enclosure

E3S Web of Conferences ◽

10.1051/e3sconf/202132104007 ◽

2021 ◽

Vol 321 ◽

pp. 04007

Author(s):

Abdelkader Boutra ◽

Seddik Kherroubi ◽

Abderrahmane Bourada ◽

Youb Khaled Benkahla ◽

Nabila Labsi ◽

...

Keyword(s):

Heat Transfer ◽

Numerical Study ◽

Industrial Applications ◽

Optimal Choice ◽

Heat Transfer Analysis ◽

Heat Conducting ◽

Algebraic Equations ◽

Pressure Line ◽

Flow And Heat Transfer ◽

Simpler Algorithm

Flow and heat transfer analysis in ventilated cavities is one of the most widely studied problems in thermo-fluids area. Two-dimensional mixed convection in a ventilated rectangular cavity with baffles is studied numerically and the fluid considered in this study is hot air (Pr = 0.71). The horizontal walls are maintained at a constant temperature, higher than that imposed on the vertical ones. Two very thin heat-conducting baffles are inserted inside the enclosure, on its horizontal walls, to control the flow of convective fluid. The governing equations are discretized using the finite volume method and the SIMPLER algorithm to treat the coupling velocity–pressure. Line by line method is used to solve iteratively the algebraic equations. The effect of the Richardson number Ri (0.01- 100) and the location of the baffles within the cavity on the isothermal lines, streamlines distributions and the average Nusselt number (Nu) has been investigated. The result shows that the location opposite the baffles, close to the fluid outlet, is the optimal choice to be considered for industrial applications.

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Influence of Melting Heat Transfer in the Stagnation-Point Flow of a Jeffrey Fluid in the Presence of Viscous Dissipation

Journal of Applied Mechanics ◽

10.1115/1.4005560 ◽

2012 ◽

Vol 79 (2) ◽

Cited By ~ 23

Author(s):

M. Mustafa ◽

T. Hayat ◽

Awatif A. Hendi

Keyword(s):

Heat Transfer ◽

Stagnation Point ◽

Viscous Dissipation ◽

Melting Process ◽

Deborah Number ◽

Stagnation Point Flow ◽

Heat Transfer Analysis ◽

Jeffrey Fluid ◽

Melting Heat ◽

Melting Heat Transfer

This communication studies the effect of melting heat transfer on the stagnation-point flow of a Jeffrey fluid over a stretching sheet. Heat transfer analysis is carried out in the presence of viscous dissipation. The arising differential system has been solved by the homotopy analysis method (HAM). The results indicate an increase in the velocity and the boundary layer thickness with an increase in the values of the elastic parameter (Deborah number) for a Jeffrey fluid which are opposite to those accounted for in the literature for the other subclasses of rate type fluids. Furthermore, an increase in the melting process corresponds to an increase in the velocity and a decrease in the temperature. A comparative study between the current computations and the previous studies is also presented in a limiting sense.

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