scholarly journals A CONSERVATIVE ADAPTIVE-MESH ALGORITHM FOR UNSTEADY, COMBINED-MODE HEAT TRANSFER USING THE DISCRETE ORDINATES METHOD

1999 ◽  
Vol 35 (4) ◽  
pp. 407-430 ◽  
Author(s):  
Louis H. Howell, Richard B. Pember,
Keyword(s):  
Heat Transfer ◽  
Adaptive Mesh ◽  
Discrete Ordinates ◽  
Discrete Ordinates Method ◽  
Combined Mode

Discrete Ordinates Method for Transient Radiation Transfer in Cylindrical Enclosures

2003 ◽  
Author(s):  
Kyunghan Kim ◽  
Zhixiong Guo
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Radiative Heat ◽  
Radiation Transfer ◽  
Radiation Heat Transfer ◽  
Discrete Ordinates ◽  
Radiation Heat ◽  
Discrete Ordinates Method ◽  
Transient Radiation ◽  
Tissue Welding

The Discrete Ordinates Method (DOM) for solving transient radiation transfer equation in cylindrical coordinates is developed for radiation heat transfer in participating turbid media in pico-scale time domain. The application problems addressed here are laser tissue welding and soldering. The novelty of this study lies with the use of ultrashort laser pulses as the irradiation source. The characteristics of transient radiation heat transfer in ultrafast laser tissue welding and soldering are studied with the DOM developed. The temporal distribution of radiative energy inside the tissue cylinder as well as the radiative heat flux on the tissue surface is obtained. Comparisons are performed between laser welding without use of solder and laser soldering with use of solder. The use of solder is found to have highly concentrated radiation energy deposition in the solder-stained region and reduce the surface radiative heat flux accordingly. Comparisons of transient radiation heat transfer between the spatially square-variance and Gaussian-variance laser inputs and between the temporally Gaussian and skewed input profiles are also conducted.

Discrete-Ordinates Solutions of the Radiative Transport Equation for Rectangular Enclosures

1984 ◽  
Vol 106 (4) ◽  
pp. 699-706 ◽  
Author(s):  
W. A. Fiveland
Keyword(s):  
Heat Transfer ◽  
Transfer Rate ◽  
Numerical Solutions ◽  
Surface Heat ◽  
Discrete Ordinates ◽  
Two Dimensional ◽  
Scattering Medium ◽  
Discrete Ordinates Method ◽  
Radiant Intensity ◽  
Radiative Transport Equation

The Sn discrete-ordinates method is used to find numerical solutions in a two-dimensional rectangular enclosure with a gray absorbing, emitting, and isotropically scattering medium. Results are obtained for the S2, S4, and S6 approximations that correspond to 4, 12, and 24 flux approximations, respectively, and are compared with exact solutions, numerical Hottel’s zone results, P3 differential approximations, and an approximation method developed by Modest. The S2 approximation solutions were found to be applicable only for several specific cases and are not recommended for general use. The S4 and S6 solutions compare favorably with other methods and can be used to predict radiant intensity and surface heat transfer rate for various surface and optical conditions.

Sign in / Sign up

Export Citation Format

Share Document