scholarly journals Numerical Investigation of Deposition Characteristics of PLA on an ABS Plate Using a Material Extrusion Process

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3404
Author(s):  
Bih-Lii Chua ◽  
Sun-Ho Baek ◽  
Keun Park ◽  
Dong-Gyu Ahn
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Finite Element ◽  
Heating Temperature ◽  
Extrusion Process ◽  
Plastic Substrate ◽  
Fe Model ◽  
Material Extrusion ◽  
Flux Model ◽  
Heat Flux Model

Three-dimensional prototypes and final products are commonly fabricated using the material extrusion (ME) process in additive manufacturing applications. However, these prototypes and products are limited to a single material using the ME process due to technical challenges. Deposition of plastic on another dissimilar plastic substrate requires proper control of printing temperature during an ME process due to differences in melting temperatures of dissimilar plastics. In this paper, deposition of PLA filament on an ABS substrate during an ME process is investigated using finite element analysis. A heat transfer finite element (FE) model for the extrusion process is proposed to estimate the parameters of the ME machine for the formulation of a heat flux model. The effects of printing temperature and the stand-off distance on temperature distributions are investigated using the proposed FE model for the extrusion process. The heat flux model is implemented in a proposed heat transfer FE model of single bead deposition of PLA on an ABS plate. From this FE model of deposition, temperature histories during the ME deposition process are estimated. The results of temperature histories are compared with experiments. Using the calibrated FE model, a proper heating temperature of ABS for deposition of PLA is evaluated.

scholarly journals Finite Element Analysis of Variable Viscosity Impact on MHD Flow and Heat Transfer of Nanofluid Using the Cattaneo–Christov Model

Coatings ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 395 ◽  
Author(s):  
Liaqat Ali ◽  
Xiaomin Liu ◽  
Bagh Ali
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Finite Element ◽  
Differential Equations ◽  
Thermal Relaxation ◽  
Fluid Temperature ◽  
Flow And Heat Transfer ◽  
Flux Model ◽  
The Impact ◽  
Heat Flux Model

In this mathematical study, magnetohydrodynamic, time-independent nanofluid flow over a stretching sheet by using the Cattaneo–Christov heat flux model is inspected. The impact of the thermal, solutal boundary and gravitational body forces with the effect of double stratification on the mass flow and heat transfer phenomena is also observed. The temperature-dependent viscosity impact on heat transfer through a moving sheet with capricious heat generation in nanofluids have studied, and the viscosity of the fluid is presumed to deviate as the inverse function of temperature. With the appropriate transformations, the system of partial differential equations is transformed into a system of nonlinear ordinary differential equations. By applying the variational finite element method, the transformed system of equations is solved. The properties of the several parameters for buoyancy, velocity, temperature, stratification, and Brownian motion parameters have examined. The enhancement in the concentration and thermal boundary layer thickness of the nanofluid sheet due to the increment in the viscosity parameter, also increased the temperature and concentration of nanoparticles. Moreover, the fluid temperature declined with the increasing values of thermal relaxation parameter. This displays that the Cattaneo–Christov heat flux model provides a better assessment of temperature distribution. Moreover, confirmation of the code and precision of the numerical method has inveterate with the valuation of the presented results with previous studies.

Direct Numerical Simulation of Turbulent Channel Flow With Heat Transfer for Low Prandtl and High Reynolds and Comparison With Algebraic Heat Flux Model

2015 ◽  
Author(s):  
Haomin Yuan ◽  
Elia Merzari
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Heat Flux ◽  
Reynolds Number ◽  
Prandtl Number ◽  
Direct Numerical Simulation ◽  
Liquid Metals ◽  
Turbulent Channel Flow ◽  
Flux Model ◽  
Heat Flux Model

The flow characteristic of fluid at low Prandtl number is of continued interest in the nuclear industry because liquid metals are to be used in the next-generation nuclear power reactors. In this work we performed direct numerical simulation (DNS) for turbulent channel flow with fluid of low Prandtl number. The Prandtl number was set to 0.025, which is representative of the behavior of liquid metals. Constant heat flux was imposed on the walls to study heat transfer behavior, with different boundary conditions for temperature fluctuation. The bulk Reynolds number was set as high as 50,000, with a corresponding friction Reynolds number of 1,200, which is closer to the situation in a reactor or a heat exchanger than used in normally available databases. Budgets for turbulent variables were computed and compared with predictions from several RANS turbulence models. In particular, the Algebraic Heat Flux Model (AHFM) has been the focus of this comparison with DNS data. The comparisons highlight some shortcomings of AHFM along with potential improvements.

Free convective heat transfer in Jeffrey fluid with suspended nanoparticles and Cattaneo–Christov heat flux

2020 ◽  
Vol 234 (3-4) ◽  
pp. 99-114
Author(s):  
B Vasu ◽  
Atul Kumar Ray ◽  
Rama SR Gorla
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Surface Temperature ◽  
Vertical Wall ◽  
Physical Parameters ◽  
Local Similarity ◽  
Species Concentration ◽  
Flux Model ◽  
Jeffrey Nanofluid ◽  
Heat Flux Model

Free convection flow of Jeffrey nanofluid past a vertical plate with sinusoidal variations of surface temperature and species concentration is presented. The study of heat transfer and nanofluid transport has been done by employing Cattaneo–Christov heat flux model and Buongiorno model, respectively. Equations governing the flow are non-dimensionalized using appropriate transformations. Furthermore, the method of local similarity and local non-similarity is used to reduce the equations into non-linear coupled system of equations which are then solved by homotopy analysis method. The obtained results are validated by comparing with the existing results available in the literature. The numerical results are found to be in good agreement. The effects of varying the physical parameters such as Deborah Number, Prandtl number, Schmidt number, thermophoresis parameter, Brownian motion parameter and buoyancy ratio parameter are obtained and presented graphically. The effect of sinusoidal variation of surface temperature and species concentration on the skin friction coefficient, Nusselt number and Sherwood number is also shown. Velocity for Jeffrey nanofluid is more than the Newtonian nanofluid while temperature and nanoparticle concentration for Jeffrey nanofluid is less than the Newtonian nanofluid. Raising value of thermal relaxation times leads to an increase in the heat transfer coefficient. It is observed that temperature of Cattaneo–Christov heat flux model is less than that in classical Fourier’s model away from the vertical wall. These types of boundary layer flow problems are found in vertical film solar energy collector, grain storage, transportation and power generation, thermal insulation, gas production, petroleum resources, geothermal reservoirs.

Heat Transfer Enhancement Feature of the Non-Fourier Cattaneo-Christov Heat Flux Model

2021 ◽  
Author(s):  
Mustafa Türkyilmazoglu
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Heat Transfer Enhancement ◽  
Transfer Rate ◽  
Transfer Enhancement ◽  
Numerical Studies ◽  
Flux Model ◽  
Heat Flux Model ◽  
Present Effort ◽  
Enhancement Property

Abstract Cattaneo-Christov heat flux model was proposed to remedy the weakness of the traditional Fourier heat flux model in order to maintain the finite travel time of heat. The literature is replete with numerical studies to understand the heat transfer enhancement property. The present effort is to provide a mathematical rigor and to analytically demonstrate why the new model should act towards cooling and thus, in the way of enhancing the heat transfer rate from the surfaces. The derived and presented formulae here prove this assertion through comparison with a few selected examples from the open literature.

Analysis of radiative nonlinear heat transfer in a convective flow of dusty fluid by capitalizing a non-Fourier heat flux model

2021 ◽  
pp. 095440892110411
Author(s):  
G. Sowmya ◽  
B. Saleh ◽  
R. J. Punith Gowda ◽  
R. Naveen Kumar ◽  
R. S. Varun Kumar ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Velocity Slip ◽  
Slip Parameter ◽  
Dusty Fluid ◽  
Thermal Fields ◽  
Curvature Parameter ◽  
Flux Model ◽  
The Impact ◽  
Heat Flux Model

The study is concerned with the heat transfer in a slip flow of a dusty fluid with the impact of a magnetic field and nonlinear thermal radiation. Furthermore, for the heat transfer process the Cattaneo–Christov heat flux model is used. Suitable similarity transformations are used to transform the governing equations. Later, shooting method and the Runge-Kutta Fehlberg's fourth fifth order (RKF-45) process are utilized to solve these reduced system of nonlinear ordinary differential equations. Impact of numerous involved parameters on the flow, thermal fields of both dust and fluid phase, skin friction and rate of heat transfer are visually plotted through graphs and discussed quantitatively. The significant outcomes drawn from the current study are that, the rise in value of the velocity slip parameter decreases the velocity profile but improves the thermal profile of both the phases. The growing values of curvature parameter intensify the flow and the thermal fields of both phases. The cumulative values of magnetic parameter and dust particle mass concentration parameter declines the velocity and thermal gradients of both phases. The thermal relaxation time parameter decays the temperature profile. The heat transfer rate is strengthened with the growing values of the curvature parameter, the velocity slip parameter, and radiation parameter.

Sign in / Sign up

Export Citation Format

Share Document