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A comparative study on classical polynomial approximations to the transport equation in spherical media albedo problems

  • A. Yılmazer and C. Kocar
Published/Copyright: April 5, 2013
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Abstract

The ultraspherical polynomial approximation which unifies all classical polynomial sequences in a unique form is used to calculate the albedo for isotropic scattering in a homogeneous spherical medium. This is the most general polynomial approach in the sense that it includes all classical polynomial methods to solve the transport equation such as and methods. For the first time an antisymmetric polynomial (ultraspherical polynomial) solution to the corresponding pseudo-slab problem is proposed. Very accurate and consistent albedo values are obtained for a variety of methods when compared to the literature. It is also shown that various approximations differ only in convergency characteristics; some converge monotonically, some in the mean.

Kurzfassung

Die ultrasphärische Polynom Approximation, die alle klassischen polynomiellen Folgen vereinheitlicht, wird zur Berechnung der Albedo für isotrope Streuung in einem homogenen kugelförmigen Medium verwendet. Dies ist der allgemeinste Polynomansatz, der alle klassichen polynomiellen Methoden zur Lösung der Transportgleichung, wie zum Beispiel und Methoden umfasst. Zum ersten Mal wird eine antisymmetrische polynomielle Lösung (ultrasphärische Polynome) für das Pseudo-Platten Problem vorgeschlagen. Man erhält sehr genaue und konsistente Albedo-Werte für verschiedene Methoden verglichen mit Werten aus der Literatur. Es wird außerdem gezeigt, dass sich verschiedene Approximationen nur in ihren Konvergenzeigenschaften unterscheiden; einige konvergieren monoton, andere im Mittel.

References

1 Sen, K. K.; Wilson, S. J.: Radiative Transfer in Curved Media. World Scientific, Singapore, 199010.1142/9789814343053Search in Google Scholar

2 Case, K. M.; Zelazny, R.; Kanal, M.: Spherically Symmetric Boundary-Value Problems in One-Speed Transport Theory. Journal of Mathematical Physics11 (1970) 223Search in Google Scholar

3 Erdmann, R. C.; Siewert, C. E.: Green's Functions for the One-speed Transport Equation in Spherical Geometry. Journal of Mathematical Physics9 (1968) 81 10.1063/1.1664481Search in Google Scholar

4 Wu, S.; Siewert, C. E.: One-Speed Transport Theory for Spherical Media with Internal Sources and Incident Radiation. Z. Angew. Math. Phys.26 (1975) 637Search in Google Scholar

5 Siewert, C. E.; Grandjean, P.: Three Basic Neutron-transport Problems in Spherical Geometry. Nuclear Science and Engineering70 (1979) 96Search in Google Scholar

6 Siewert, C. E.; Thomas, J. R.: Particle Transport Theory in a Finite Sphere Containing a Spherical-Shell Source. Nuclear Science and Engineering81 (1983) 285Search in Google Scholar

7 Siewert, C. E.; Thomas, J. R.: Radiative Transfer Calculations in Spheres and Cylinders. Journal of Quantitative Spectroscopy and Radiative Transfer34 (1985) 5910.1016/0022-4073(85)90171-2Search in Google Scholar

8 Abulwafa, E. M.: Radiative-transfer in a Linearly-anisotropic Spherical Medium. Journal of Quantitative Spectroscopy and Radiative Transfer49 (1993) 16510.1016/0022-4073(93)90057-OSearch in Google Scholar

9 El-Wakil, S. A.; Haggag, M. A.; Attia, M. T.; Saad, E. A.: Radiative Transfer in an Inhomogeneous Sphere. Journal of Quantitative Spectroscopy and Radiative Transfer40 (1988) 7110.1016/0022-4073(88)90032-5Search in Google Scholar

10 Thynell, S. T.; Ozisik, M. N.: Radiation Transfer in an Isotropically Scattering Homogeneous Solid Sphere. Journal of Quantitative Spectroscopy and Radiative Transfer33 (1985) 31910.1016/0022-4073(85)90193-1Search in Google Scholar

11 Tsai, J. R.; Ozisik, M. N.; Santarelli, F.: Radiation in Spherical Symmetry with Anisotropic Scattering and Variable Properties. Journal of Quantitative Spectroscopy and Radiative Transfer42 (1989) 18710.1016/0022-4073(89)90082-4Search in Google Scholar

12 Wilson, S. J.; Nada, T. R.: Radiative Transfer in Absorbing, Emitting and Linearly Anisotropically Scattering Inhomogeneous Solid Spheres. Journal of Quantitative Spectroscopy and Radiative Transfer44 (1990) 34510.1016/0022-4073(90)90012-USearch in Google Scholar

13 El-Wakil, S. A.; Degheidy, A. R.; Machali, H. M.; El-Depsy, A.: Radiative Transfer in a Spherical Medium. Journal of Quantitative Spectroscopy and Radiative Transfer69 (2001) 4910.1016/S0022-4073(00)00061-3Search in Google Scholar

14 Atalay, M. A.: On the Radiative Transfer in a Spherical Medium. International Journal of Thermal Sciences45 (2006) 45210.1016/j.ijthermalsci.2005.04.011Search in Google Scholar

15 Mitsis, G. J.: Transport Solutions to the Monoenergetic Critical Problem. ANL-6787, 196310.2172/4118021Search in Google Scholar

16 Yilmazer, A.: Spectral Approximations to the Transport Problems in Spherical Media. Journal of Quantitative Spectroscopy and Radiative Transfer108 (2007) 40310.1016/j.jqsrt.2007.04.005Search in Google Scholar

17 Sahni, D. C.; Sharma, A.: Computation of Higher Spherical Harmonics Moments of the Angular Fux for Neutron Transport Problems in Spherical Geometry. Annals of Nuclear Energy27 (2000) 411Search in Google Scholar

18 Sharma, A.: Spherical Harmonics Moments of Neutron Angular Flux for Spherically Symmetric Systems. Annals of Nuclear Energy28 (2001) 715Search in Google Scholar

19 Yilmazer, A.; Tombakoglu, M.: On Equiconvergence of Ultraspherical Polynomials Solution of One-Speed Neutron Transport Equation. Annals of Nuclear Energy33 (2006) 957Search in Google Scholar

20 Davison, B.: Neutron Transport Theory. Oxford University Press, London, 195810.1063/1.3062414Search in Google Scholar

Received: 2008-8-27
Published Online: 2013-04-05
Published in Print: 2008-11-01

© 2008, Carl Hanser Verlag, München

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