Performance of DOM and IDA with different angular discretization methods in 3-D absorbing-emitting-scattering media

Ozen, Guzide
Selçuk, Nevin
Predicted accuracy and computationally efficiency of Discrete Ordinates Method (DOM) and Improved Differential Approximation (IDA) were evaluated by applying both methods to cubical enclosure problems containing purely isotropically/linearly anisotropically scattering/absorbing-emitting-isotropically scattering medium and comparing their predictions with benchmark solutions available in the literature. Performances of DOM and IDA with S-8, S-10 and T-4 quadratures were assessed by comparing their predictions against benchmark solutions. DOM with S-8 and IDA with T-4 were found to provide more accurate and efficient solutions compared to other discretization schemes. However, overall comparisons reveal that DOM S-8 produces higher accuracy and computational efficiency than IDA T-4 on all test problems under consideration.


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Selçuk, Nevin (1997-01-01)
The discrete ordinates method (DOM) and discrete transfer method (DTM) were evaluated from the viewpoints of both predictive accuracy and computational economy by comparing their predictions with exact solutions available from a box-shaped enclosure problem with steep temperature gradients. Comparative testing shows that the S-4 approximation produces better accuracy in radiative energy source term than in flux density in three orders of magnitude less CPU time than that required by the DTM. The S-4 approxi...
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Compensation of Temperature and Acceleration effects on MEMS Gyroscope
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Applications of hybrid discrete Fourier transform-moment method to the fast analysis of large rectangular dipole arrays printed on a thin grounded dielectric substrate
Chou, HT; Ko, HK; Aydın Çivi, Hatice Özlem; ERTÜRK, VAKUR BEHÇET (2002-08-05)
Recently a discrete Fourier transform-method of moments (DFT-MoM) scheme was developed for fast analysis of electrically large rectangular planar dipole arrays, which has been shown to be very efficient in terms of number reduction of unknown variables and computational complexity. The applications of this DFT-MoM to treat dipole arrays printed on a grounded dielectric substrate are examined in this Letter. Numerical results are presented to validate its efficiency and accuracy. (C) 2002 Wiley Periodicals, ...
Citation Formats
G. Ozen and N. Selçuk, “Performance of DOM and IDA with different angular discretization methods in 3-D absorbing-emitting-scattering media,” INTERNATIONAL JOURNAL OF THERMAL SCIENCES, pp. 104–110, 2013, Accessed: 00, 2020. [Online]. Available: