Solution of diffusion-advection equation of radon transport in many-layered geological media

• Autorzy: Yakovleva V. S. , Parovik R. I.
• Konferencja: Proceedings of the International Conference "Radon in Environment" 10-14 May 2009, Zakopane Poland
• Języki publikacji: EN

Abstrakty

EN

Radon transport modeling in geological media is an important tool for solving problems and tasks of radioecology and geophysics. Comparison of radon field time series obtained by numerical and experimental methods is one of the most common and widely applicable ways to analyze the influence of state and variability of meteorological, electrical and actinometric parameters of atmosphere, cosmic weather factors, variations of deflected mode of geological medium on the level and variations of radon field. The solutions of stationary and non-stationary diffusion-advection equations of radon transport in many-layered geological media by numerical methods, notably by integro-interpolation method (balance method) are presented. The peculiarity of radon transport in many-layered media is taken into account in the developed numerical model. This peculiarity is connected with the transport equation coefficients which can change very rapidly at the border of two adjacent layers, i.e. they can be discontinuous at the borders of each layer that can be caused by parameters of soils greatly differing in value (density, porosity, radium content, diffusion and emanation coefficients). The present work is provided with an example of application of the developed numerical model for solving a practical problem on assessment of influence of deep seated uranium-containing rock on the value of radon volumetric activity at the depth of less-than or equal to 1 m. The article considers non-stationary numerical model calculations showing at what time moments the distribution curves of radon volumetric activity coincide with stationary regime of radon transport in geological media. The validity of the developed numerical solution has been confirmed by these calculations.

Słowa kluczowe

EN

radon; diffusion; advection; transport; modeling; soil

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2010
• Tom: Vol. 55, No. 4
• Strony: 601--606
• Opis fizyczny: Bibliogr. 11 poz., rys.

Twórcy

autor

Yakovleva V. S.

autor

Parovik R. I.

• Applied Physics Department, Tomsk Polytechnic University, 30 Lenin pr., Tomsk, 634050, Russian Federation, Tel.: [phone], Fax: [phone],

Bibliografia

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• 7. Program for numerical modeling of radon transport in porous many-layered media SimRaTran. Certificate of Branch Registration of Inventions (2008) no. 11729 byYakovleva VS, www.ofap.ru
• 8. Samarsky AA, Vabishevich PN (2004) Numerical methods of convection-diffusion problems solution, 3rd ed. Editorial USSR, Moscow (in Russian)
• 9. van der Spoel WH, van der Graaf ER, de Meijer RJ (1998) Combined diffusive and advective transport of radon in a homogeneous column of dry sand. Health Sci 74;1:48–63
• 10. Yakovleva VS (2005) A theoretical method for estimating the characteristics of radon transport in homogeneous soil. Ann Geophys 48;1:195–198
• 11. Yakovleva VS, Ryzhakova NK (2003) A method for estimating the convective radon transport velocity in soils. Radiat Meas 36;1:389–391