scholarly journals Prediction of the Superficial Heat Source Parameters for TIG Heating Process Using FEM and ANN Modeling

Entropy ◽  
2019 ◽  
Vol 21 (10) ◽  
pp. 954
Author(s):  
Joanna Wróbel ◽  
Adam Kulawik
Keyword(s):  
Heat Source ◽  
Boundary Conditions ◽  
Source Parameters ◽  
Experimental Studies ◽  
Heating Process ◽  
Process Conditions ◽  
Actual Process ◽  
Heating Treatment ◽  
Steady State Heat ◽  
Steady State Heat Transfer

The basic problem of the numerical model’s quenching process is establishing the characteristics of the boundary conditions. The existing descriptions of the boundary conditions, which represent the parameters of equipment used in heat treatment processes, do not accurately reflect the actual process conditions. In the present study, the method of choice for superficial heat source parameters for TIG (tungsten inert gas) heating is modeled using artificial neural networks (ANN) and the finite element method (FEM). A comparison of the calculations obtained from the numerical model of non-steady state heat transfer with the results of the experimental studies is presented. The possibility of using ANN to compute the parameters of the boundary conditions for the heating treatment is analyzed. A multilayer feed-forward backpropagation network is developed and trained using value of temperature in the selected nodes obtained from numerical simulation.

Elastocaloric Cooling With Ni-Ti Based Alloys: Material Characterization and Process Variation

2015 ◽  
Author(s):  
Marvin Schmidt ◽  
Johannes Ullrich ◽  
André Wieczorek ◽  
Jan Frenzel ◽  
Andreas Schütze ◽  
...  
Keyword(s):  
Solid State ◽  
Heat Source ◽  
Boundary Conditions ◽  
Shape Memory ◽  
Heat Sink ◽  
Operating Conditions ◽  
Process Conditions ◽  
Cooling Process ◽  
Elastocaloric Cooling ◽  
Latent Heats

Solid state refrigeration processes, such as magnetocaloric and electrocaloric refrigeration, have recently shown to be a promising alternative to conventional compression refrigeration. A new solid state elastocaloric refrigeration process using the latent heats within Shape Memory Alloys (SMA) could also hold potential in this field. This work investigates the elastocaloric effects in Ni-Ti-based superelastic Shape Memory Alloy (SMA) systems for use in an elastocaloric cooling processes. Ni-Ti alloys exhibits large latent heats and a small mechanical hysteresis, which may potentially lead to the development of an efficient environmentally friendly solid-state cooling system, without the need for ozone-depleting refrigerants. A systematic investigation of the SMA is conducted using a novel custom-built scientific testing platform specifically designed to measure cooling process related phenomena. This testing system is capable of performing tensile tests at high rates as well as measuring and controlling the solid-state heat transfer between SMA and heat source/heat sink. Tests are conducted following a cooling process related training cycle where the material has achieved stabilized behavior. First, a characterization of the elastocaloric material properties is performed followed by an investigation of the material under cooling process conditions. A comprehensive monitoring of the mechanical and thermal parameters enables the observation of temperature changes during mechanical cycling of the SMA at high strain rates. These observations can be used to study the rate dependent efficiency of the elastocaloric material. The measurement of the temperature of both the heat source/heat sink and the SMA itself, as well as the required mechanical work during a running cooling process, reveals the influence of the operating conditions on the elastocaloric effect of the material. Furthermore investigations of the process efficiency at different thermal boundary conditions (temperature of heat source/heat sink), indicates that the process is dependent on the boundary conditions which have to be controlled in order to optimize the efficiency.

scholarly journals The Influence of Welding Heat Source Inclination on the Melted Zone Shape, Deformations and Stress State of Laser Welded T-Joints

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5303
Author(s):  
Zbigniew Saternus ◽  
Wiesława Piekarska ◽  
Marcin Kubiak ◽  
Tomasz Domański
Keyword(s):  
Stress State ◽  
Numerical Analysis ◽  
Heat Source ◽  
Source Parameters ◽  
Experimental Studies ◽  
Welding Process ◽  
Experimental Tests ◽  
Material Model ◽  
Numerical Calculations ◽  
Heating Source

The paper concerns the numerical analysis of the influence for three different of welding heat source inclinations on the weld pool shape and mechanical properties of the resulting joint. Numerical analysis is based on the experimental tests of single-side welding of two sheets made of X5CrNi18-10 stainless steel. The joint is made using a laser welding heat source. Experimental test was performed for one heating source inclination. As a part of the work metallographic tests are performed on which the quality of obtained joints are determined. Numerical calculations are executed in Abaqus FEA. The same geometrical model is assumed as in the experiment. Material model takes into account changing with temperature thermophysical properties of austenitic steel. Modeling of the motion of heating source is performed in additional subroutine. The welding source parameters are assumed in accordance with the welding process parameters. Numerical calculations were performed for three different inclinations of the source. One inclination is consistent with experimental studies. The performed numerical calculations allowed to determine the temperature field, shape of welding pool as well as deformations and stress state in welded joint. The obtained results are compared to results of the experiment.

scholarly journals Some Exact Solutions of Nonlinear Fin Problem for Steady Heat Transfer in Longitudinal Fin with Different Profiles

2014 ◽  
Vol 2014 ◽  
pp. 1-16 ◽  
Author(s):  
M. D. Mhlongo ◽  
R. J. Moitsheki
Keyword(s):  
Heat Transfer ◽  
Boundary Conditions ◽  
Neumann Boundary ◽  
Dirichlet Boundary Conditions ◽  
Temperature Dependent ◽  
Fin Efficiency ◽  
Highly Nonlinear ◽  
Steady State Heat ◽  
Steady State Heat Transfer ◽  
Steady Heat

One-dimensional steady-state heat transfer in fins of different profiles is studied. The problem considered satisfies the Dirichlet boundary conditions at one end and the Neumann boundary conditions at the other. The thermal conductivity and heat coefficients are assumed to be temperature dependent, which makes the resulting differential equation highly nonlinear. Classical Lie point symmetry methods are employed, and some reductions are performed. Some invariant solutions are constructed. The effects of thermogeometric fin parameter, the exponent on temperature, and the fin efficiency are studied.

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

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.

scholarly journals Higher Order Multiscale Finite Element Method for Heat Transfer Modeling

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3827
Author(s):  
Marek Klimczak ◽  
Witold Cecot
Keyword(s):  
Heat Transfer ◽  
Finite Element Method ◽  
Finite Element ◽  
Degrees Of Freedom ◽  
Higher Order ◽  
Shape Functions ◽  
Multiscale Finite Element Method ◽  
Multiscale Finite Element ◽  
Steady State Heat ◽  
Steady State Heat Transfer

In this paper, we present a new approach to model the steady-state heat transfer in heterogeneous materials. The multiscale finite element method (MsFEM) is improved and used to solve this problem. MsFEM is a fast and flexible method for upscaling. Its numerical efficiency is based on the natural parallelization of the main computations and their further simplifications due to the numerical nature of the problem. The approach does not require the distinct separation of scales, which makes its applicability to the numerical modeling of the composites very broad. Our novelty relies on modifications to the standard higher-order shape functions, which are then applied to the steady-state heat transfer problem. To the best of our knowledge, MsFEM (based on the special shape function assessment) has not been previously used for an approximation order higher than p = 2, with the hierarchical shape functions applied and non-periodic domains, in this problem. Some numerical results are presented and compared with the standard direct finite-element solutions. The first test shows the performance of higher-order MsFEM for the asphalt concrete sample which is subject to heating. The second test is the challenging problem of metal foam analysis. The thermal conductivity of air and aluminum differ by several orders of magnitude, which is typically very difficult for the upscaling methods. A very good agreement between our upscaled and reference results was observed, together with a significant reduction in the number of degrees of freedom. The error analysis and the p-convergence of the method are also presented. The latter is studied in terms of both the number of degrees of freedom and the computational time.

Numerical Simulation on Heat Dissipating Performance of New Pipe with Grid Plate

2012 ◽  
Vol 532-533 ◽  
pp. 417-421
Author(s):  
Chang Li Song ◽  
Jing Ji
Keyword(s):  
Heat Transfer ◽  
Simulation Analysis ◽  
Heat Transfer Analysis ◽  
Finite Element Software ◽  
Grid Plate ◽  
Steady State Heat ◽  
Steady State Heat Transfer ◽  
Energy Conservation Law ◽  
Optimal Diameter ◽  
Selection Of

In order to improve the pipe dissipating area, a kind of new pipe with grid plate is proposed in this paper. Based on the basic principle of heat transfer and energy conservation law, by finite element software ANSYS the simulation analysis of the steady-state heat transfer of the new pipeline is carried out, process of ANSYS modeling, loading and solving is introduced in detail, the distribution of temperature and stress for pipe with a grid plate is given, these can provide the foundation for the selection of the optimal diameter of the grid plate and transient heat transfer analysis of pipe.

Sign in / Sign up

Export Citation Format

Share Document