Frictional Heating of a Composite

1994 ◽  
Vol 116 (3) ◽  
pp. 415-422 ◽  
Author(s):  
Shingo Obara ◽  
Takahisa Kato
Keyword(s):  
Temperature Distribution ◽  
Frictional Heating ◽  
Three Dimensional ◽  
Numerical Procedure ◽  
Surface Profile ◽  
Asperity Contact ◽  
Infinite Body ◽  
Contact Heat ◽  
Moving Surface ◽  
Worn Surface

A numerical analysis has been carried out for a three-dimensional frictional heating problem of a composite material, in which an asperity contact (heat source) moves across the boundary of the constituents of a composite. The mathematical model adopted here is that a surface asperity on a semi-infinite body slides on a composite which consists of two semi-infinite bodies. Expressions of temperature distribution both in the composite and on the moving surface are derived. Then the temperature distribution and its change with time are obtained by a numerical procedure. It is shown that the temperature rise caused by frictional heating remarkably depends on the thermal properties of constituents of the composite, and temperature distributions in the vicinity of the asperity contact both on the moving surface and in the composite rapidly change when the asperity passes over the boundary of the constituents. The effect of the frictional heating on the worn surface profile of a composite is also discussed.

Effect of Thermal Distortion on Wear of Composites

1995 ◽  
Vol 117 (4) ◽  
pp. 622-628 ◽  
Author(s):  
Shingo Obara ◽  
Takahisa Kato
Keyword(s):  
Elastic Deformation ◽  
Composite Structure ◽  
Frictional Heating ◽  
Tetragonal Zirconia ◽  
Surface Profile ◽  
Normal Pressure ◽  
Oxide Ceramic ◽  
Thermal Distortion ◽  
Test Results ◽  
Worn Surface

The worn surface profile of a composite structure was experimentally and numerically investigated focusing on the effects of sliding conditions. Wear tests on composites made of an oxide ceramic and an amorphous metal against a tetragonal zirconia polycrystals-alumina were carried out under various mean contact pressures, P, and sliding velocities, V. The test results showed that the worn surface profiles of the composites changed with the PV value. A new numerical method for simulating the worn surface profile of a composite structure has been developed. The present method is based upon the assumption that the profile of a worn surface is changed by thermal distortion of the sliding bodies due to frictional heating and by elastic deformation due to normal pressure and friction traction. The calculated results were compared with the test results, and the comparison showed that the elastic deformation plays an important role in forming the worn surface profile and that the effect of thermal distortion becomes remarkable with an increase in PV values. The numerical results clarified the contribution of the thermal distortion to the change in the worn surface profile of the composite.

A modified approach based on bearing area curve for surface wear characterization

2020 ◽  
Vol 72 (3) ◽  
pp. 273-278
Author(s):  
Yun Wang ◽  
Junhong Mao ◽  
Suwen Lu ◽  
Zhenying Xu ◽  
Hong Liu ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Surface Profile ◽  
Surface Wear ◽  
H13 Steel ◽  
Wear Area ◽  
Content Type ◽  
Profile Method ◽  
Wear Analysis ◽  
Curve Method ◽  
Worn Surface

Purpose Wear greatly influences the machine lifetime, performance and reliability and its quantification is very important. This paper aims to propose a modified bearing area curve method by combining the theory of the bearing area curve, and the relocation technique to calculate wear accurately and efficiently. Design/methodology/approach H13 steel was chosen as the material of wear pair, and the wear experiments were carried out at 50 N, 60 r/min for 20 min. The surface was measured before and after wear experiments. The relocation was made by comparing the mean lines (planes) of the unworn and worn surface profiles. The calculated results using the proposed method were compared with that of the surface profile method for a two-dimensional surface to validate its accuracy. The method was then applied for a three-dimensional (3D) wear analysis. Findings The worn surface shows clearly displacement compared to the unworn surface and implies the importance of including relocation in the bearing area curve method. The results from the proposed method are 98 per cent close to that from the surface profile method, indicating that the method is accurate for wear evaluation. Originality/value As no feature point or relocation mark is needed to calculate the relocation value using the proposed method, the method can be applied to mild to severe wear. Also, as the deviation of different scans does not affect the relocation calculation, and no matching and stitching is required, this method can be easily applied to a wide wear area and 3D surface wear analysis.

A Three-Dimensional Thermal-Mechanical Asperity Contact Model for Two Nominally Flat Surfaces in Contact

2000 ◽  
Vol 123 (3) ◽  
pp. 595-602 ◽  
Author(s):  
Geng Liu ◽  
Qian Wang ◽  
Shuangbiao Liu
Keyword(s):  
Frictional Heating ◽  
Three Dimensional ◽  
Contact Model ◽  
Asperity Contact ◽  
The Finite Element Method ◽  
Flat Surfaces ◽  
Solution Methods ◽  
Steady State Heat ◽  
Steady State Heat Transfer ◽  
Rough Surface Contact

The rough surface contact in a tribological process involves frictional heating and thermoelastic deformations. A three-dimensional thermal-mechanical asperity contact model has been developed, which takes into account steady-state heat transfer, asperity distortion due to thermal and elastic deformations, and material yield. The finite-element method (FEM), fast Fourier transform (FFT), and conjugate gradient method (CGM) are employed as the solution methods. The model is used to analyze the thermal-mechanical contact of typical rough surfaces and investigate the importance of thermal effects on the contact performance of surface asperities.

scholarly journals Wear of sprag clutch wedge in overrun state under high temperature condition

2021 ◽  
Vol 13 (2) ◽  
pp. 168781402199651
Author(s):  
Jia Li ◽  
Hongzhi Yan ◽  
Minghao Lin ◽  
Mengkai Cai ◽  
Xuan Hu
Keyword(s):  
High Temperature ◽  
Testing Machine ◽  
Three Dimensional ◽  
Surface Profile ◽  
Orthogonal Experimental Design ◽  
Wear Depth ◽  
Wear Model ◽  
Theoretical Support ◽  
Worn Surface ◽  
Abrasion Testing

A formula is proposed based on Archard’s wear model to calculate wedge wear depth in a positive continuous engagement (PCE)-type sprag clutch with double-disc inner cam wedge in the overrun state. Methods to solve for the equation parameters are proposed. Using a sprag clutch with an M50 steel wedge as an example, wedge wear depth variation over time under high temperatures was analyzed. An easy-to-clamp wedge was designed and a high-temperature abrasion testing machine was used to test the wedge. The worn surface profile was observed using a three-dimensional profiler and the wedge wear depth was obtained. The effects of lubrication, temperature and speed on wear were analyzed using mixed-level orthogonal experimental design. Results show that the theoretical values are consistent with test values. Therefore, the model can be used to calculate wear accurately for the overrunning sprag clutch. Lubrication affects wear depth significantly, whereas temperature has a smaller effect and speed has very little influence. Within the experimental scope, when the temperature increased by 1°C, the wear depth increased by approximately 0.0145 μm and when the speed increased by approximately 1 time/minute, the wear depth increased by 0.00854 μm. These results provide theoretical support for optimal sprag clutch design.

Boundary Condition Design to Heat a Moving Object at Uniform Transient Temperature Using Inverse Formulation

2004 ◽  
Vol 126 (3) ◽  
pp. 619-626 ◽  
Author(s):  
Hakan Ertu¨rk ◽  
Ofodike A. Ezekoye ◽  
John R. Howell
Keyword(s):  
Boundary Condition ◽  
Temperature Distribution ◽  
Design Problem ◽  
Manufacturing Industry ◽  
Three Dimensional ◽  
Chemical Deposition ◽  
Iterative Solution ◽  
Conveyor Belt ◽  
Temperature History ◽  
Transient Temperature

The boundary condition design of a three-dimensional furnace that heats an object moving along a conveyor belt of an assembly line is considered. A furnace of this type can be used by the manufacturing industry for applications such as industrial baking, curing of paint, annealing or manufacturing through chemical deposition. The object that is to be heated moves along the furnace as it is heated following a specified temperature history. The spatial temperature distribution on the object is kept isothermal through the whole process. The temperature distribution of the heaters of the furnace should be changed as the object moves so that the specified temperature history can be satisfied. The design problem is transient where a series of inverse problems are solved. The process furnace considered is in the shape of a rectangular tunnel where the heaters are located on the top and the design object moves along the bottom. The inverse design approach is used for the solution, which is advantageous over a traditional trial-and-error solution where an iterative solution is required for every position as the object moves. The inverse formulation of the design problem is ill-posed and involves a set of Fredholm equations of the first kind. The use of advanced solvers that are able to regularize the resulting system is essential. These include the conjugate gradient method, the truncated singular value decomposition or Tikhonov regularization, rather than an ordinary solver, like Gauss-Seidel or Gauss elimination.

scholarly journals Simulation of Thermal and Electric Field Distribution in Packaged Sausages Heated in a Stationary Versus a Rotating Microwave Oven

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1622
Author(s):  
Wipawee Tepnatim ◽  
Witchuda Daud ◽  
Pitiya Kamonpatana
Keyword(s):  
Temperature Distribution ◽  
Electric Field ◽  
Three Dimensional ◽  
Development Stage ◽  
Microwave Oven ◽  
Computational Time ◽  
Plastic Package ◽  
Heating Uniformity ◽  
The Cost ◽  
Good Agreement

The microwave oven has become a standard appliance to reheat or cook meals in households and convenience stores. However, the main problem of microwave heating is the non-uniform temperature distribution, which may affect food quality and health safety. A three-dimensional mathematical model was developed to simulate the temperature distribution of four ready-to-eat sausages in a plastic package in a stationary versus a rotating microwave oven, and the model was validated experimentally. COMSOL software was applied to predict sausage temperatures at different orientations for the stationary microwave model, whereas COMSOL and COMSOL in combination with MATLAB software were used for a rotating microwave model. A sausage orientation at 135° with the waveguide was similar to that using the rotating microwave model regarding uniform thermal and electric field distributions. Both rotating models provided good agreement between the predicted and actual values and had greater precision than the stationary model. In addition, the computational time using COMSOL in combination with MATLAB was reduced by 60% compared to COMSOL alone. Consequently, the models could assist food producers and associations in designing packaging materials to prevent leakage of the packaging compound, developing new products and applications to improve product heating uniformity, and reducing the cost and time of the research and development stage.

Process Modeling in Laser Deposition of Multilayer SS410 Steel

2007 ◽  
Vol 129 (6) ◽  
pp. 1028-1034 ◽  
Author(s):  
Liang Wang ◽  
Sergio Felicelli
Keyword(s):  
Phase Transformation ◽  
Temperature Distribution ◽  
Three Dimensional ◽  
Element Model ◽  
Traverse Speed ◽  
Processing Parameters ◽  
Dimensional Finite Element ◽  
Net Shaping ◽  
Three Dimensional Finite Element ◽  
Continuous Cooling Transformation Diagram

A three-dimensional finite element model was developed to predict the temperature distribution and phase transformation in deposited stainless steel 410 (SS410) during the Laser Engineered Net Shaping (LENS™) rapid fabrication process. The development of the model was carried out using the SYSWELD software package. The model calculates the evolution of temperature in the part during the fabrication of a SS410 plate. The metallurgical transformations are taken into account using the temperature-dependent material properties and the continuous cooling transformation diagram. The ferritic and martensitic transformation as well as austenitization and tempering of martensite are considered. The influence of processing parameters such as laser power and traverse speed on the phase transformation and the consequent hardness are analyzed. The potential presence of porosity due to lack of fusion is also discussed. The results show that the temperature distribution, the microstructure, and hardness in the final part depend significantly on the processing parameters.

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