Analysis of Gas Convection and Temperature Distribution in a Rotating Wafer in a Cylindrical Lamp Heating Apparatus

2002 ◽  
Author(s):  
Shigeki Hirasawa ◽  
Shigenao Maruyama
Keyword(s):  
Heat Transfer ◽  
Temperature Distribution ◽  
Thermal Processing ◽  
Radiation Heat Transfer ◽  
Three Dimensional ◽  
Convection Heat Transfer ◽  
Heat Transfer Analysis ◽  
Gas Velocity ◽  
Radiation Heat ◽  
Heating Rates

A three-dimensional radiation-heat-transfer analysis and a convection-heat-transfer analysis are combined in order to determine the temperature distribution in a rotating wafer in a cylindrical lamp heating apparatus for rapid thermal processing. The calculated results show that the temperature variation in the wafer increases 1.4 K by the effect of natural convection, when inlet gas velocity is 0.1 m/s during 1273 K steady-state heating of the non-rotating wafer. The effect of gas convection on the temperature variations in the wafer can be minimized when the wafer is rotating in an axisymmetric apparatus and the heating rates of the lamps are optimally controlled.

Analysis to Reduce Thermal Stress in Oxide Single Crystal During Czochralski Growth

2004 ◽  
Author(s):  
Shigeki Hirasawa ◽  
Hiroyuki Ishibashi ◽  
Kazuhisa Kurashige ◽  
Akihiro Gunji
Keyword(s):  
Heat Transfer ◽  
Thermal Stress ◽  
Temperature Distribution ◽  
Thermal Radiation ◽  
Single Crystal ◽  
Radiation Heat Transfer ◽  
Heat Transfer Analysis ◽  
Czochralski Growth ◽  
Radiation Heat ◽  
Radial Temperature

Temperature distributions and thermal stress distributions in a semi-transparent GSO crystal during Czochralski (CZ) single crystal growth were numerically investigated by thermal radiation heat transfer analysis and anisotropy stress analysis. As GSO has special optical properties, such as semi-transparency at a wavelength shorter than 4.5 μm, thermal radiation heat transfer was calculated by the Monte Carlo method. These calculations showed that thermal stress is caused by the radial temperature distribution on the outside of the upper part of the crystal. To reduce this temperature distribution, the following three manufacturing conditions were found to be effective: use a sharp taper angle of the crystal, install a lid to the top of the insulator, and install a ring around the tapered part of the crystal.

A Numerical Investigation of Ray Tracing Method in a View Factor Calculation Procedure for Zonal Radiation Heat Transfer in Complex Systems

2009 ◽  
Author(s):  
German Malikov ◽  
Vladimir Lisienko ◽  
Roman Koptelov ◽  
Jakov Kalugin ◽  
Raymond Viskanta
Keyword(s):  
Heat Transfer ◽  
Ray Tracing ◽  
Direct Method ◽  
Radiation Heat Transfer ◽  
Three Dimensional ◽  
Heat Transfer Analysis ◽  
View Factor ◽  
Radiation Heat ◽  
Zonal Method ◽  
Metallurgical Furnaces

In this paper a variety of well known computer graphics algorithms (Binary Spatial Partitioning-BSP, Bounding Box-BB, and direct method of sequential search) for ray tracing are studied numerically in the context of the view factor calculations for the zonal method of radiation heat transfer analysis in complex industrial furnace geometries. The paper reports on a modified BSP algorithm which takes into account the specific types of obstructions and their arrangement in different types of metallurgical furnaces. The modified algorithm enhances the ray tracing calculations by two to three orders of magnitude. An universal algorithm to obtain an intersection with a polyhedron obstruction is developed. The method is tested for simple three dimensional and complex furnace geometries.

Monte Carlo Simulation of Radiative Heat Transfer in Rapid Thermal Processing (RTP) Systems

1994 ◽  
Vol 342 ◽  
Author(s):  
J. Vernon Cole ◽  
Karson L. Knutson ◽  
Klavs F. Jensen
Keyword(s):  
Heat Transfer ◽  
Monte Carlo ◽  
Thermal Processing ◽  
Measurement Techniques ◽  
Radiation Heat Transfer ◽  
Rapid Thermal Processing ◽  
Three Dimensional ◽  
General Purpose ◽  
Radiation Heat ◽  
Participating Media

ABSTRACTWe present a general purpose Monte Carlo method for the simulation of radiation heat transfer in rapid thermal processing (RTP) chambers. Three-dimensional mesh generation software is used to discretize the surfaces within the system, allowing the simulation of realistic chamber and reflector designs. An adaptive subdivision of the chamber geometry reduces the number of raysurface intersections which must be computed. The method models internal reflection, absorption, and transmission within participating media, and includes wavelength, temperature, and material dependent optical properties. Radiation heat transfer simulations are used to examine a reflector assembly, and to test the assumptions of optical wafer temperature measurement techniques.

scholarly journals Three-dimensional radiation heat transfer analysis in a cylindrical gas reformer by the radiative heat ray method.

1989 ◽  
Vol 55 (514) ◽  
pp. 1724-1728
Author(s):  
Hiroshi TANIGUCHI ◽  
Kazuhiko KUDO ◽  
Naoki KUMAGAI ◽  
Kehui GUO ◽  
Takao KATAYAMA ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Radiative Heat ◽  
Radiation Heat Transfer ◽  
Three Dimensional ◽  
Heat Transfer Analysis ◽  
Radiation Heat ◽  
Ray Method

scholarly journals Experimental and Computational Investigations of Phase Change Thermal Energy Storage Canisters

2000 ◽  
Vol 122 (4) ◽  
pp. 176-182 ◽  
Author(s):  
Mounir Ibrahim ◽  
Pavel Sokolov ◽  
Thomas Kerslake ◽  
Carol Tolbert
Keyword(s):  
Heat Transfer ◽  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Radiation Heat Transfer ◽  
Convection Heat Transfer ◽  
Melting Time ◽  
Radiation Heat ◽  
Space Experiments

Two sets of experimental data for cylindrical canisters with thermal energy storage applications were examined in this paper: 1) Ground Experiments and 2) Space Experiments. A 2-D computational model was developed for unsteady heat transfer (conduction and radiation) with phase-change. The radiation heat transfer employed a finite volume method. The following was found in this study: 1) Ground Experiments, the convection heat transfer is equally important to that of the radiation heat transfer; Radiation heat transfer in the liquid is found to be more significant than that in the void; Including the radiation heat transfer in the liquid resulted in lower temperatures (about 15 K) and increased the melting time (about 10 min.); Generally, most of the heat flow takes place in the radial direction. 2) Space Experiments, Radiation heat transfer in the void is found to be more significant than that in the liquid (exactly the opposite to the Ground Experiments); Accordingly, the location and size of the void affects the performance considerably; Including the radiation heat transfer in the void resulted in lower temperatures (about 40 K). [S0199-6231(00)00304-X]

Design Studies for a Solar Reactor Based on a Simple Radiative Heat Exchange Model

2005 ◽  
Vol 127 (3) ◽  
pp. 425-429 ◽  
Author(s):  
C. Wieckert
Keyword(s):  
Heat Transfer ◽  
Solar Power ◽  
Radiation Heat Transfer ◽  
Heat Transfer Analysis ◽  
Physical Parameters ◽  
Concentrated Solar Power ◽  
Radiation Heat ◽  
Small Aperture ◽  
Lower Cavity ◽  
Solar Reactor

A high-temperature solar chemical reactor for the processing of solids is scaled up from a laboratory scale (5kW concentrated solar power input) to a pilot scale (200kW). The chosen design features two cavities in series: An upper cavity has a small aperture to let in concentrated solar power coming from the top. It serves as the solar receiver, radiant absorber, and radiant emitter to a lower cavity. The lower cavity is a well-insulated enclosure. It is subjected to thermal radiation from the upper cavity and serves in our application as the reaction chamber for a mixture of ZnO and carbon. Important insight for the definition of the geometrical parameters of the pilot reactor has been generated by a radiation heat transfer analysis based on the radiosity enclosure theory. The steady-state model accounts for radiation heat transfer within the solar reactor including reradiation losses through the reactor aperture, wall losses due to thermal conduction and heat consumption by the endothermic chemical reaction. Key results include temperatures of the different reactor walls and the thermal efficiency of the reactor as a function of the major geometrical and physical parameters. The model, hence, allows for a fast estimate of the influence of these parameters on the reactor performance.

scholarly journals Evaluation of radiation heat transfer in porous medial: Application for a pebble bed modular reactor cooled by CO2 gas

2013 ◽  
Vol 28 (2) ◽  
pp. 118-127
Author(s):  
Kamel Sidi-Ali ◽  
Khaled Oukil ◽  
Tinhinane Hassani ◽  
Yasmina Amri ◽  
Abdelmoumane Alem
Keyword(s):  
Heat Transfer ◽  
Porous Medium ◽  
Free Convection ◽  
Radiation Heat Transfer ◽  
Convection Heat Transfer ◽  
Emergency Situation ◽  
System Of Equations ◽  
Radiation Heat ◽  
Pebble Bed ◽  
Free Convection Heat

This work analyses the contribution of radiation heat transfer in the cooling of a pebble bed modular reactor. The mathematical model, developed for a porous medium, is based on a set of equations applied to an annular geometry. Previous major works dealing with the subject have considered the forced convection mode and often did not take into account the radiation heat transfer. In this work, only free convection and radiation heat transfer are considered. This can occur during the removal of residual heat after shutdown or during an emergency situation. In order to derive the governing equations of radiation heat transfer, a steady-state in an isotropic and emissive porous medium (CO2) is considered. The obtained system of equations is written in a dimensionless form and then solved. In order to evaluate the effect of radiation heat transfer on the total heat removed, an analytical method for solving the system of equations is used. The results allow quantifying both radiation and free convection heat transfer. For the studied situation, they show that, in a pebble bed modular reactor, more than 70% of heat is removed by radiation heat transfer when CO2 is used as the coolant gas.

Simulation of Radiation Heat Transfer of Three Dimensional Participating Media by Radiative Exchange Method

2008 ◽  
Author(s):  
Mohammad Hadi Bordbar ◽  
Timo Hyppa¨nen
Keyword(s):  
Heat Transfer ◽  
Balance Equation ◽  
Radiation Heat Transfer ◽  
Three Dimensional ◽  
Radiation Balance ◽  
Scattering Media ◽  
Radiation Heat ◽  
Exchange Method ◽  
Participating Media ◽  
Radiative Exchange

This paper describes the theoretical bases of the Radiative Exchange Method, a new numerical method for simulating radiation heat transfer. By considering radiative interaction between all points of the geometry and solving the radiation balance equation in a mesh structure coarser than the structure used in computational fluid flow calculation, this method is able to simulate radiative heat transfer in arbitrary 3D space with absorbing, emitting and scattering media surrounded by emitting, absorbing and reflecting surfaces. A new concept is introduced, that of the exchange factors between the different elements that are necessary for completing the radiative balance equation set. Using this method leads to a set of algebraic equations for the radiative outgoing power from each coarse cell being produced and the result of this set of equations was then used to calculate the volumetric radiative source term in the fine cell structure. The formulation of the exchange factor for a three-dimensional state and also a mesh size analysis that was conducted to optimize the accuracy and runtime are presented. The results of this model to simulate typical 3D furnace shape geometry, is verified by comparison with those of other numerical methods.

Sign in / Sign up

Export Citation Format

Share Document