Design Optimization of Induction Heater in Planetary Reactors for Semiconductor Industry

2015 ◽  
Vol 792 ◽  
pp. 505-510 ◽  
Author(s):  
Aleksandr Nikanorov ◽  
Bernard Nacke ◽  
Tatiana Zedler
Keyword(s):  
Temperature Distribution ◽  
Thermal Stresses ◽  
Semiconductor Industry ◽  
Three Dimensional ◽  
Induction Coil ◽  
Temperature Dependent ◽  
Thermal Calculations ◽  
Three Dimensional Models ◽  
Account Temperature ◽  
Coil Shape

One application of induction heating is a planetary reactor for deposition of compound semiconductor layers from the gas phase. High temperature needed for the process is provided by a “pancake” induction coil. Temperature distribution in the reactor influences the deposition quality as well as the lifetime of the reactor components. The induction coil shape has been improved by numerical modelling combined with automatic optimization. The developed two-and three-dimensional models include coupled electromagnetic and thermal calculations to take into account temperature dependent material properties. Three-dimensional structural analysis, based on the predicted temperature distribution, was used to estimate the level of the appeared thermal stresses in the reactor parts. The received optimal design of the induction coil has been successfully tested in the industrial planetary reactor.

Optimization of Organ Freezing Protocols With Specified Allowable Thermal Stress Levels

2000 ◽  
Author(s):  
Brian H. Dennis ◽  
George S. Dulikravich ◽  
Yoed Rabin
Keyword(s):  
Temperature Distribution ◽  
Thermal Stresses ◽  
Three Dimensional ◽  
Genetic Optimization ◽  
Local Cooling ◽  
Temperature Dependent ◽  
Nonlinear Constrained Optimization ◽  
Unsteady Heat Conduction ◽  
Novel Concept ◽  
Cryo Preservation

Abstract A novel concept of determining optimized cooling protocols for freezing three-dimensional organs has been developed and its feasibility examined computationally. The concept is based on determining correct spatial variation of temperature distribution on the walls of a freezing container at every instant of time during the cooling process so that local thermal stresses in the heterogeneous organ are always kept below a specified level while maximizing the local cooling rates. The cryo-preservation medium must be gelatin which prevents thermal convection. The optimized cooling protocol was simulated by developing a time-accurate finite element computer program to predict unsteady heat conduction with phase change and thermal stresses within a realistically shaped and sized organ made of tissues with temperature-dependent physical properties. A micro-genetic optimization algorithm was then used to achieve nonlinear constrained optimization of parameterized time-varying container wall temperature distribution so that the prescribed maximum allowable thermal stresses are never exceeded in the organ.

Numerical Simulation Investigation on Single-Layer Multi-Tracks Laser Milling of Al2O3 Ceramic

2014 ◽  
Vol 971-973 ◽  
pp. 111-114
Author(s):  
Zhao Mei Xu ◽  
Zong Hai Hong ◽  
Qing An Wang ◽  
Hai Bing Wu
Keyword(s):  
Temperature Distribution ◽  
Laser Beam ◽  
Parametric Design ◽  
Three Dimensional ◽  
Single Layer ◽  
Element Model ◽  
Temperature Dependent ◽  
Laser Milling ◽  
Transient Thermal ◽  
Account Temperature

Regional-input high-power laser beam inevitably leads to inhomogeneous and instable temperature distribution of laser milling(LM) process. Knowledge of thermal of multi-track LM is critical to understand the interaction of different milling tracks. Taking into account temperature-dependent thermal conduction and heat capacity, a three-dimensional transient thermal finite element model has been developed. The moving laser beam is simulated with the employment of ANSYS parametric design language and latent heat is considered by using enthalpy. Several conclusions according to the simulation results were produced, comparing with the previous track, the latter one has larger heat affected region and larger in homogeneous temperature distribution; the greatest temperature gradient takes place near the edges of milling part where the scanning direction changes.

Residual Stress Simulation of Stud Welding in a Rectangular Steel Tubular Surface

2010 ◽  
Vol 44-47 ◽  
pp. 581-585
Author(s):  
Lei Wang ◽  
Qi Lin Zhang ◽  
Lu Chen
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Thermal Stresses ◽  
Three Dimensional ◽  
Element Model ◽  
Stud Welding ◽  
Tubular Surface ◽  
Three Dimensional Models ◽  
Transient Thermal ◽  
Stress Simulation

A thermal-mechanical coupled finite element model has been presented to predict residual and thermal stresses during different stages of stud welding. The finite study was carried out using three-dimensional models. To enhance the accuracy of the numerical solution material properties including physical, thermal and mechanical properties supposed to be temperature-dependent. After the temperature distributions as a result of welding were calculated, thermal and residual stress values obtained. Residual stresses are attributed to the elasto-plastic response of the object towards the transient thermal stresses generated by the welding. After all temperature values reach the room temperature, the residual stresses decrease to a small value.

Thermal Stresses in Thick-Walled Circular Cylinders Under Axisymmetric Temperature Distribution

1971 ◽  
Vol 93 (4) ◽  
pp. 969-975 ◽  
Author(s):  
K. W. Yang ◽  
C. W. Lee
Keyword(s):  
Temperature Distribution ◽  
Thin Shell ◽  
Shell Theory ◽  
Thermal Stresses ◽  
Three Dimensional ◽  
Circular Cylinders ◽  
Curved Surfaces ◽  
Present Solution ◽  
Axisymmetric Temperature ◽  
Thin Shell Theory

A series solution is obtained for thick-walled cylinders subjected to a temperature distribution which varies both radially and axially. The solution is based on three-dimensional linear theory of thermoelasticity, with appropriate approximations by neglecting small terms and using St. Venant’s principle. The internal and external curved surfaces are assumed traction-free. In each series of the solution the first term is identical to the thin shell theory and the subsequent correcting terms are expressed in increasing powers of the thickness-to-radius ratio. An illustrative example problem is solved by using the present solution, and the numerical results are compared with those based on the thin shell theory.

scholarly journals MAXIMUM ALLOWABLE THERMAL STRESSES CALCULATION OF WATER TUBE BOILER DURING OPERATION

2019 ◽  
Vol 7 (7) ◽  
pp. 191-199
Author(s):  
Asa Elmaryami ◽  
Abdulla Sousi ◽  
Walid Saleh ◽  
Sharefa El-Mabrouk Abd El-Mawla ◽  
Mohamed Elshayb
Keyword(s):  
Temperature Distribution ◽  
Thermal Stresses ◽  
Three Dimensional ◽  
Industrial Sector ◽  
Limiting Factors ◽  
Steam Boiler ◽  
Two Dimensional ◽  
Water Tube ◽  
Cartesian Coordinate ◽  
Tube Life

In steam boiler industrial sector, pressure and temperature of the water tube are the two main factors that affecting the safety and efficiency of a steam boiler. Explosions may be occurring because of a sudden drop in pressure without a corresponding drop in temperature. Therefore, understanding the temperature distribution of the water tube boiler is essential control the failure and explosion of the boiler. Once the temperature distribution is known then the limiting factors that affect the water tube life such as maximum allowable thermal stresses can be determined. ANSYS software will be used to determine the temperature distribution in the water tube of a utility boiler during operation at elevated inlet water and furnace temperature. The theory of axisymmetric has been utilized since water- tube is cylindrical in shape. In axisymmetric theory, a three-dimensional cylindrical problem like water tube can be reduced to two dimensional by ignoring the circumferential Ө, while r-axis and z-axis became x-axis and y-axis or Cartesian coordinate. Then two-dimensional rectangular elements meshing for the profile cross-section along the water tube in r and z axes were implemented in a computerize simulation using ANSYS 10 to find out the steady state temperature distribution of the water tube.

A photothermoelastic investigation of transient thermal stresses in wing ribs

1972 ◽  
Vol 7 (2) ◽  
pp. 117-124 ◽  
Author(s):  
E Matsumoto ◽  
S Sumi ◽  
T Sekiya
Keyword(s):  
Temperature Distribution ◽  
Thermal Stresses ◽  
Three Dimensional ◽  
Composite Model ◽  
New Technique ◽  
Transient Temperature ◽  
Transient Temperature Distribution ◽  
Transient Thermal

The photothermoelastic method of refrigeration has been used to study the problem of a long beam under transient temperature distribution and good correlation with the theoretical values has been obtained. The new technique for three-dimensional photothermoelasticity, which uses a composite model made of photoelastically sensitive and insensitive materials, is suggested for the analysis of idealized wing-rib structures.

Predicting Residual Thermal Stresses in Friction Stir Welding

2003 ◽  
Author(s):  
Mir H. Zahedul Khandkar ◽  
Jamil A. Khan
Keyword(s):  
Friction Stir Welding ◽  
Residual Stresses ◽  
Thermal Model ◽  
Thermal Stresses ◽  
Three Dimensional ◽  
Welding Process ◽  
Temperature History ◽  
Temperature Dependent ◽  
Friction Stir ◽  
Input Torque

Sequentially coupled finite element models of the friction stir welding process have been proposed to study the residual stresses caused by the thermal cycles during friction stir welding of metals. This is a two step simulation process. In the first step, the thermal history is predicted from an input torque based thermal model. The temperature history generated by the thermal model is then sequentially coupled to a mechanical model that predicts the residual stresses. The model does not deal with the severe plastic deformations within the weld nugget and the thermo-mechanically affected regions, a fact that may cause modeled results to deviate from experimentally measured residual stresses. The model is three dimensional and uses temperature dependent material and thermophysical properties.

Plastic replicas as three-dimensional models of pulps

1975 ◽  
Vol 39 (8) ◽  
pp. 544-546
Author(s):  
HL Wakkerman ◽  
GS The ◽  
AJ Spanauf
Keyword(s):  
Three Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models
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