PORE-SCALE NUMERICAL STUDY ON THE HEAT TRANSFER PROCESS IN POROUS MEDIA UNDER DIFFERENT THERMAL CONDITIONS

2018 ◽  
Author(s):  
Shen DU ◽  
Ming-Jia Li ◽  
Zhan-Bin Liu ◽  
Ya-Ling He ◽  
Wen-Quan Tao
Keyword(s):  
Heat Transfer ◽  
Porous Media ◽  
Transfer Process ◽  
Numerical Study ◽  
Thermal Conditions ◽  
Heat Transfer Process ◽  
Pore Scale

Numerical Study on the Effect of Inner Tube Position on Heat Transfer Process in Self-Recuperative Radiant Tube

2011 ◽  
Vol 228-229 ◽  
pp. 676-680 ◽  
Author(s):  
Ye Tian ◽  
Xun Liang Liu ◽  
Zhi Wen
Keyword(s):  
Heat Transfer ◽  
Transfer Process ◽  
Numerical Study ◽  
Flame Temperature ◽  
Three Dimensional ◽  
Mathematic Model ◽  
Heat Transfer Process ◽  
Bulk Temperature ◽  
Radiant Tube ◽  
Peak Value

A three-dimensional mathematic model is developed for a 100kw single-end recuperative radiant tube and the simulation is performed with the CFD software FLUENT. Also it is used to investigate the effect of distance between combustion chamber exit and inner tube on heat transfer process. The results suggest that the peak value of combustion flame temperature drops along with the increasing of distance, which leads to low NOX discharging. Also radiant tube surface bulk temperature decreases, which causes radiant tube heating performance losses.

scholarly journals CFD SIMULATION OF THE HEAT TRANSFER PROCESS IN A CHEVRON PLATE HEAT EXCHANGER USING THE SST TURBULENCE MODEL

2015 ◽  
Vol 55 (4) ◽  
pp. 267 ◽  
Author(s):  
Jan Skočilas ◽  
Ievgen Palaziuk
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Transfer Process ◽  
Cfd Simulation ◽  
Numerical Study ◽  
Analytical Calculation ◽  
Heat Transfer Process ◽  
Plate Heat Exchanger ◽  
Hot Water ◽  
Plate Heat

<p>This paper deals with a computational fluid dynamics (CFD) simulation of the heat transfer process during turbulent hot water flow between two chevron plates in a plate heat exchanger. A three-dimensional model with the simplified geometry of two cross-corrugated channels provided by chevron plates, taking into account the inlet and outlet ports, has been designed for the numerical study. The numerical model was based on the shear-stress transport (SST) <em>k-!</em> model. The basic characteristics of the heat exchanger, as values of heat transfer coefficient and pressure drop, have been investigated. A comparative analysis of analytical calculation results, based on experimental data obtained from literature, and of the results obtained by numerical simulation, has been carried out. The coefficients and the exponents in the design equations for the considered plates have been arranged by using simulation results. The influence on the main flow parameters of the corrugation inclination angle relative to the flow direction has been taken into account. An analysis of the temperature distribution across the plates has been carried out, and it has shown the presence of zones with higher heat losses and low fluid flow intensity.</p>

scholarly journals Numerical Study on Heat Transfer Performance in Packed Bed

Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 414 ◽  
Author(s):  
Shicheng Wang ◽  
Chenyi Xu ◽  
Wei Liu ◽  
Zhichun Liu
Keyword(s):  
Heat Transfer ◽  
Thermal Resistance ◽  
Transfer Process ◽  
Heat Transfer Performance ◽  
Numerical Study ◽  
Continuous Phase ◽  
Heat Transfer Process ◽  
Packed Beds ◽  
Transfer Performance ◽  
Entransy Dissipation

Packed beds are widely used in industries and it is of great significance to enhance the heat transfer between gas and solid states inside the bed. In this paper, numerical simulation method is adopted to investigate the heat transfer principle in the bed at particle scale, and to develop the direct enhanced heat transfer methods in packed beds. The gas is treated as continuous phase and solved by Computational Fluid Dynamics (CFD), while the particles are treated as discrete phase and solved by the Discrete Element Method (DEM); taking entransy dissipation to evaluate the heat transfer process. Considering the overall performance and entransy dissipation, the results show that, compared with the uniform particle size distribution, radial distribution of multiparticle size can effectively improve the heat transfer performance because it optimizes the velocity and temperature field, reduces the equivalent thermal resistance of convection heat transfer process, and the temperature of outlet gas increases significantly, which indicates the heat quality of the gas has been greatly improved. The increase in distribution thickness obviously enhances heat transfer performance without reducing the equivalent thermal resistance in the bed. The result is of great importance for guiding practical engineering applications.

Controlled Temperature Distribution and Heat Transfer Process in the Unidirectional Solidification of Aluminium Alloys

2012 ◽  
Vol 188 ◽  
pp. 314-317
Author(s):  
Florin Ştefănescu ◽  
Gigel Neagu ◽  
Alexandrina Mihai ◽  
Iuliana Stan
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Temperature Distribution ◽  
Transfer Process ◽  
Thermal Conditions ◽  
Solidification Process ◽  
Heat Transfer Process ◽  
Solidification Structure ◽  
Major Influence ◽  
Cast Material

Abstract. The paper presents some theoretical and experimental data regarding the directional solidification, revealing the main factors (especially those which are related to the heat transfer process) which have influence on the crystals size and morphology. The crystalline structure of alloys is determined by three important factors: chemical composition, thermal conditions, and characteristics of germination and growth from liquid of solid nuclei. The solidification structure can be influenced by acting on the mould properties or directly on the cast material, both of these actions being based upon the change of temperature distribution in the alloy-mould system. Experimental data demonstrated the major influence of the thermal regime on the crystallization-solidification process, on the transcrystallization zone and they pointed out the limits to direct the crystals formation (size and shape) by changing the cooling regime.

NUMERICAL STUDY OF HEAT TRANSFER IN EXTENDED SURFACESWITH MUTUAL RADIATION BETWEEN PARALLEL FINS

2018 ◽  
Vol 17 (1) ◽  
pp. 80
Author(s):  
R. L. Sobral ◽  
J. M. Quirino ◽  
E. D. Correa ◽  
R. M. S. Gama
Keyword(s):  
Heat Transfer ◽  
Transfer Process ◽  
Numerical Study ◽  
Minimum Principle ◽  
Radiation Heat Transfer ◽  
Elliptic Partial Differential Equation ◽  
Heat Transfer Process ◽  
Radiative Heat Exchange ◽  
Thermal Interaction ◽  
Linear Problems

The present work shows the influence of the mutual heat transfer on the effectiveness of finned surfaces. Numerical simulations are carried out through a sequence of linear problems, possessing an equivalent minimum principle, that has as its limit the solution of the original problem. The original nonlinear problem is regarded as the limit (which always exists) of a sequence of linear problems like the classical conduction-convection ones. In this work the nonlinear conduction-radiation heat transfer process is considered and simulated by means of a finite difference linear scheme. Such a limit is reached in an easy way by means of standard procedures, allowing the employment of more realistic hypotheses, like some nonlinear boundary conditions, since the mathematical complexities are not a constraint for simulating the elliptic partial differential equation. This work accounts for the the steady state heat transfer process in rigid fins which experiences convective and radiative heat exchange. Some typical results are shown in order to illustrate the methodology. Results have shown both the relevance of the radiation and the importance of the thermal interaction between the fins, so that there is an effective and realistic thermal mapping. Neglecting the thermal interaction can lead to errors of up to 20 percent.

Sign in / Sign up

Export Citation Format

Share Document