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Artykuły w czasopismach na temat "Finite-difference time-domain method"

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Doerr, Christopher R. "Sparse Finite Difference Time Domain Method". IEEE Photonics Technology Letters 25, nr 23 (grudzień 2013): 2259–62. http://dx.doi.org/10.1109/lpt.2013.2285181.

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Sorrentino, R., L. Roselli i P. Mezzanotte. "Time reversal in finite difference time domain method". IEEE Microwave and Guided Wave Letters 3, nr 11 (listopad 1993): 402–4. http://dx.doi.org/10.1109/75.248513.

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Saitoh, I., Y. Suzuki i N. Takahashi. "The symplectic finite difference time domain method". IEEE Transactions on Magnetics 37, nr 5 (2001): 3251–54. http://dx.doi.org/10.1109/20.952588.

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Masoudi, H. M., M. A. AlSunaidi i J. M. Arnold. "Time-domain finite-difference beam propagation method". IEEE Photonics Technology Letters 11, nr 10 (październik 1999): 1274–76. http://dx.doi.org/10.1109/68.789715.

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Wang, Shumin, Robert Lee i Fernando L. Teixeira. "Implicit nonstaggered finite-difference time-domain method". Microwave and Optical Technology Letters 45, nr 4 (2005): 317–19. http://dx.doi.org/10.1002/mop.20809.

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Hong, Ic-Pyo. "2D Finite Difference Time Domain Method Using the Domain Decomposition Method". Journal of the Korean Institute of Information and Communication Engineering 17, nr 5 (31.05.2013): 1049–54. http://dx.doi.org/10.6109/jkiice.2013.17.5.1049.

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Tirkas, P. A., i C. A. Balanis. "Finite-difference time-domain method for antenna radiation". IEEE Transactions on Antennas and Propagation 40, nr 3 (marzec 1992): 334–40. http://dx.doi.org/10.1109/8.135478.

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Chen, J., i J. Wang. "Weakly conditionally stable finite-difference time-domain method". IET Microwaves, Antennas & Propagation 4, nr 11 (2010): 1927. http://dx.doi.org/10.1049/iet-map.2009.0542.

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Zhao, Huawei, Stuart Crozier i Feng Liu. "A high definition, finite difference time domain method". Applied Mathematical Modelling 27, nr 5 (maj 2003): 409–19. http://dx.doi.org/10.1016/s0307-904x(03)00049-0.

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Schneider, R. N., M. M. Okoniewski i L. E. Turner. "Finite-difference time-domain method in custom hardware?" IEEE Microwave and Wireless Components Letters 12, nr 12 (grudzień 2002): 488–90. http://dx.doi.org/10.1109/lmwc.2002.805948.

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Rozprawy doktorskie na temat "Finite-difference time-domain method"

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Eng, Ju-Ling. "Higher order finite-difference time-domain method". Connect to resource, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1165607826.

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Ciydem, Mehmet. "Ray Based Finite Difference Method For Time Domain Electromagnetics". Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606633/index.pdf.

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In this study, novel Ray Based finite difference method for Time Domain electromagnetics(RBTD) has been developed. Instead of solving Maxwell&rsquo
s hyperbolic partial differential equations directly, Geometrical Optics tools (wavefronts, rays) and Taylor series have been utilized. Discontinuities of electromagnetic fields lie on wavefronts and propagate along rays. They are transported in the computational domain by transport equations which are ordinary differential equations. Then time dependent field solutions at a point are constructed by using Taylor series expansion in time whose coefficients are these transported distincontinuties. RBTD utilizes grid structure conforming to wave fronts and rays and treats all electromagnetic problems, regardless of their dimensions, as one dimensional problem along the rays. Hence CFL stability condition is implemented always at one dimensional eqaulity case on the ray. Accuracy of RBTD depends on the accuracy of grid generation and numerical solution of transport equations. Simulations for isotropic medium (homogeneous/inhomogeneous) have been conducted. Basic electromagnetic phenomena such as propagation, reflection and refraction have been implemented. Simulation results prove that RBTD eliminates numerical dispersion inherent to FDTD and is promising to be a novel method for computational electromagnetics.
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Petit, Frédéric. "Reverberation Chamber Modeling Using Finite-Difference Time-Domain Method". Diss., University of Marne la Vallée, 2002. http://hdl.handle.net/10919/71555.

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Since the last few years, the unprecedented growth of communication systems involving the propagation of electromagnetic waves is particularly due to developments in mobile phone technology. The reverberation chamber is a reliable bench-test, enabling the study of the effects of electromagnetic waves on a specific electronic appliance. However, the operating of a reverberation chamber being rather complicated, development of numerical models are of utmost importance to determine the crucial parameters to be considered.This thesis consists in the modelling and the simulation of the operating principles of a reverberation chamber by means of the Finite-Difference Time-Domain method. After a brief study based on field and power measurements performed in a reverberation chamber, the second chapter deals with the different problems encountered during the modelling. The consideration of losses being a very important factor in the operating of the chamber, two methods of implementation of these losses are set out in this chapter. Chapter~3 consists in the analysis of the influence of the stirrer on the first eigenmodes of the chamber; the latter modes can undergo a frequency shift of several MHz. Chapter~4 shows a comparison of results issued from high frequency simulations and theoretical statistical results. The problem of an object placed in the chamber, resulting in a field disturbance is also tackled. Finally, in the fifth chapter, a comparison of statistical results for stirrers having different shapes is set out.
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Turer, Ibrahim. "Specific Absorption Rate Calculations Using Finite Difference Time Domain Method". Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605200/index.pdf.

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This thesis investigates the problem of interaction of electromagnetic radiation with human tissues. A Finite Difference Time Domain (FDTD) code has been developed to model a cellular phone radiating in the presence of a human head. In order to implement the code, FDTD difference equations have been solved in a computational domain truncated by a Perfectly Matched Layer (PML). Specific Absorption Rate (SAR) calculations have been carried out to study safety issues in mobile communication.
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Krishnaiah, K. Mohana. "Novel stable subgridding algorithm in finite difference time domain method". Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262808.

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Meagher, Timothy P. "A New Finite Difference Time Domain Method to Solve Maxwell's Equations". PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4389.

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We have constructed a new finite-difference time-domain (FDTD) method in this project. Our new algorithm focuses on the most important and more challenging transverse electric (TE) case. In this case, the electric field is discontinuous across the interface between different dielectric media. We use an electric permittivity that stays as a constant in each medium, and magnetic permittivity that is constant in the whole domain. To handle the interface between different media, we introduce new effective permittivities that incorporates electromagnetic fields boundary conditions. That is, across the interface between two different media, the tangential component, Er(x,y), of the electric field and the normal component, Dn(x,y), of the electric displacement are continuous. Meanwhile, the magnetic field, H(x,y), stays as continuous in the whole domain. Our new algorithm is built based upon the integral version of the Maxwell's equations as well as the above continuity conditions. The theoretical analysis shows that the new algorithm can reach second-order convergence O(∆x2)with mesh size ∆x. The subsequent numerical results demonstrate this algorithm is very stable and its convergence order can reach very close to second order, considering accumulation of some unexpected numerical approximation and truncation errors. In fact, our algorithm has clearly demonstrated significant improvement over all related FDTD methods using effective permittivities reported in the literature. Therefore, our new algorithm turns out to be the most effective and stable FDTD method to solve Maxwell's equations involving multiple media.
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Cai, Ming. "Finite difference time domain method and its application in antenna analysis". Thesis, London South Bank University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263739.

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Tomiso, Nayon. "Modeling electrically small apertures using the finite difference-time domain method". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42597.

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Abalenkovs, Maksims. "Huygens subgridding for the frequency-dependent/finite-difference time-domain method". Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/huygens-subgridding-for-the-frequencydependentfinitedifference-timedomain-method(45581358-ff4d-4699-b3db-5bf76a021601).html.

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Computer simulation of electromagnetic behaviour of a device is a common practice in modern engineering. Maxwell's equations are solved on a computer with help of numerical methods. Contemporary devices constantly grow in size and complexity. Therefore, new numerical methods should be highly efficient. Many industrial and research applications of numerical methods need to account for the frequency dependent materials. The Finite-Difference Time-Domain (FDTD) method is one of the most widely adopted algorithms for the numerical solution of Maxwell's equations. A major drawback of the FDTD method is the interdependence of the spatial and temporal discretisation steps, known as the Courant-Friedrichs-Lewy (CFL) stability criterion. Due to the CFL condition the simulation of a large object with delicate geometry will require a high spatio-temporal resolution everywhere in the FDTD grid. Application of subgridding increases the efficiency of the FDTD method. Subgridding decomposes the simulation domain into several subdomains with different spatio-temporal resolutions. The research project described in this dissertation uses the Huygens Subgridding (HSG) method. The frequency dependence is included with the Auxiliary Differential Equation (ADE) approach based on the one-pole Debye relaxation model. The main contributions of this work are (i) extension of the one-dimensional (1D) frequency-dependent HSG method to three dimensions (3D), (ii) implementation of the frequency-dependent HSG method, termed the dispersive HSG, in Fortran 90, (iii) implementation of the radio environment setting from the PGM-files, (iv) simulation of the electromagnetic wave propagating from the defibrillator through the human torso and (v) analysis of the computational requirements of the dispersive HSG program.
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Garg, Nimisha. "Analysis of Slot Antennas Using the Finite Difference Time Domain Method". FIU Digital Commons, 2001. https://digitalcommons.fiu.edu/etd/3843.

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The objective of this thesis was to analyze a Coplanar Waveguide (CPW)-fed folded slot antenna using the Finite Difference Time Domain (FDTD) method. Important parameters such as S-parameters and the input impedance of the antenna were simulated using XFDTD software and were analyzed. An important goal of this thesis was to provide design information about the folded slot antenna. For this purpose the effects of antenna layout on the resonant frequency and the bandwidth of the antenna were investigated. First the effect of adding more number of slots to the basic CPW-fed folded slot antenna geometry on the S-parameters, the input impedance and the radiation patterns of the antenna were studied. Next the width of the slot was varied and the effect of changing this design parameter of the antenna was analyzed. Finally the slot separation was varied and its effect on the antenna parameters is studied. This work concluded that, by including additional slots, the input impedance of the antenna can be controlled over a wide range.
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Książki na temat "Finite-difference time-domain method"

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Wenhua, Yu, red. Parallel finite-difference time-domain method. Boston, MA: Artech House, 2006.

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Computational electrodynamics: The finite-difference time-domain method. Boston: Artech House, 1995.

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C, Hagness Susan, red. Computational electrodynamics: The finite-difference time-domain method. Wyd. 3. Boston: Artech House, 2005.

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C, Hagness Susan, red. Computational electrodynamics: The finite-difference time-domain method. Wyd. 2. Boston: Artech House, 2000.

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J, Luebbers Raymond, red. The finite difference time domain method for electromagnetics. Boca Raton: CRC Press, 1993.

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Elsherbeni, Atef Z. The finite-difference time-domain method for electromagnetics with MATLAB simulations. Raleigh, NC: SciTech Pub., 2008.

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ElMahgoub, Khaled, Fan Yang i Atef Elsherbeni. Scattering Analysis of Periodic Structures Using Finite-Difference Time-Domain Method. Cham: Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-031-01713-1.

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Elsherbeni, Atef. The Finite-Difference Time-Domain Method for Electromagnetics with MATLAB Simulations. US: Scitech Publishing, Inc, 2008.

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Introduction to the finite-difference time-domain (FDTD) method for electromagnetics. San Rafael, Calif. (1537 Fourth Street, San Rafael, CA 94901 USA): Morgan & Claypool, 2011.

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Yeffet, Amir. A non-dissipative staggered fourth-order accurate explicit finite difference scheme for the time-domain Maxwell's equations. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1999.

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Części książek na temat "Finite-difference time-domain method"

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Sakamoto, Shinichi, Hideo Tsuru, Masahiro Toyoda i Takumi Asakura. "Finite-Difference Time-Domain Method". W Computational Simulation in Architectural and Environmental Acoustics, 11–51. Tokyo: Springer Japan, 2014. http://dx.doi.org/10.1007/978-4-431-54454-8_2.

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Archambeault, Bruce, Colin Brench i Omar M. Ramahi. "The Finite-Difference Time-Domain Method". W EMI/EMC Computational Modeling Handbook, 35–70. Boston, MA: Springer US, 2001. http://dx.doi.org/10.1007/978-1-4615-1557-9_3.

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Archambeault, Bruce, Omar M. Ramahi i Colin Brench. "The Finite-Difference Time-Domain Method". W EMI/EMC Computational Modeling Handbook, 35–67. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4757-5124-6_3.

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Rylander, Thomas, Pär Ingelström i Anders Bondeson. "The Finite-Difference Time-Domain Method". W Computational Electromagnetics, 63–92. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-5351-2_5.

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Manolatou, Christina, i Hermann A. Haus. "The Finite Difference Time Domain (FDTD) Method". W Passive Components for Dense Optical Integration, 35–52. Boston, MA: Springer US, 2002. http://dx.doi.org/10.1007/978-1-4615-0855-7_3.

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Sukhoivanov, Igor A., i Igor V. Guryev. "Finite-Difference Time-Domain Method for PhC Devices Modeling". W Photonic Crystals, 103–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-02646-1_6.

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ElMahgoub, Khaled, Fan Yang i Atef Elsherbeni. "FDTD Method and Periodic Boundary Conditions". W Scattering Analysis of Periodic Structures Using Finite-Difference Time-Domain Method, 5–25. Cham: Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-031-01713-1_2.

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van Ewijk, Lucas J. "The finite difference time domain method on a massively parallel computer". W High-Performance Computing and Networking, 593–98. Berlin, Heidelberg: Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/3-540-61142-8_601.

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ElMahgoub, Khaled, Fan Yang i Atef Elsherbeni. "Dispersive Periodic Structures". W Scattering Analysis of Periodic Structures Using Finite-Difference Time-Domain Method, 41–59. Cham: Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-031-01713-1_4.

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ElMahgoub, Khaled, Fan Yang i Atef Elsherbeni. "Skewed Grid Periodic Structures". W Scattering Analysis of Periodic Structures Using Finite-Difference Time-Domain Method, 27–40. Cham: Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-031-01713-1_3.

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Streszczenia konferencji na temat "Finite-difference time-domain method"

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Masumnia-Bisheh, Khadijeh, i Cynthia Furse. "Geometrically Stochastic Finite Difference Time Domain Method". W 2019 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting. IEEE, 2019. http://dx.doi.org/10.1109/apusncursinrsm.2019.8888624.

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Bommaraju, Chakrapani, i Rene Marklein. "A Novel Low-Dispersive (2,2) Finite Difference Method: 3-D Case". W 2007 Workshop on Computational Electromagnetics in Time-Domain. IEEE, 2007. http://dx.doi.org/10.1109/cemtd.2007.4373515.

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Dhawan, Prerak, i Bhooshan Paradkar. "Transformation optics using finite-difference time-domain method". W Photonic and Phononic Properties of Engineered Nanostructures IX, redaktorzy Ali Adibi, Shawn-Yu Lin i Axel Scherer. SPIE, 2019. http://dx.doi.org/10.1117/12.2506607.

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Yamaji, Masakazu, Uno Toru i Takuji Arima. "Stabilized multiple-region finite-difference time-domain method". W 2017 IEEE International Conference on Computational Electromagnetics (ICCEM). IEEE, 2017. http://dx.doi.org/10.1109/compem.2017.7912813.

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Obayya, S. S. A., i D. Pinto. "New Alternating-Direction-Implicit Finite-Difference-Time-Domain Method for Photonic Crystal Devices". W 2007 Workshop on Computational Electromagnetics in Time-Domain. IEEE, 2007. http://dx.doi.org/10.1109/cemtd.2007.4373529.

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Gaochao Zhang i Zhixiang Huang. "High stability symplectic filtered finite-difference time-domain method". W 2016 Progress in Electromagnetic Research Symposium (PIERS). IEEE, 2016. http://dx.doi.org/10.1109/piers.2016.7734689.

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Arnold, J. M. "Geometrical optics and the finite-difference time-domain method". W 2012 International Conference on Electromagnetics in Advanced Applications (ICEAA). IEEE, 2012. http://dx.doi.org/10.1109/iceaa.2012.6328784.

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Zhu, Min, Lei Zhao i Qunsheng Cao. "Optimized high-order finite-difference time-domain (2, 4) method". W 2015 IEEE International Conference on Computational Electromagnetics (ICCEM). IEEE, 2015. http://dx.doi.org/10.1109/compem.2015.7052649.

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Durbano, J. P., J. R. Humphrey, F. E. Ortiz, P. F. Curt, D. W. Prather i M. S. Mirotznik. "Hardware acceleration of the 3D finite-difference time-domain method". W IEEE Antennas and Propagation Society Symposium, 2004. IEEE, 2004. http://dx.doi.org/10.1109/aps.2004.1329557.

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Rodohan, D. P. "Parallel implementations of the finite difference time domain (FDTD) method". W Second International Conference on Computation in Electromagnetics. IEE, 1994. http://dx.doi.org/10.1049/cp:19940093.

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Raporty organizacyjne na temat "Finite-difference time-domain method"

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Mei, Kenneth K. Conformal Time Domain Finite Difference Method of Solving Electromagnetic Wave Scattering. Fort Belvoir, VA: Defense Technical Information Center, październik 1988. http://dx.doi.org/10.21236/ada200921.

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Meagher, Timothy. A New Finite Difference Time Domain Method to Solve Maxwell's Equations. Portland State University Library, styczeń 2000. http://dx.doi.org/10.15760/etd.6273.

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Beker, B. Application of the Finite-Difference Time-Domain Method to Scattering and Radiation Problems Involving Wires and Plates. Fort Belvoir, VA: Defense Technical Information Center, grudzień 1992. http://dx.doi.org/10.21236/ada268396.

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Russo, David, i William A. Jury. Characterization of Preferential Flow in Spatially Variable Unsaturated Field Soils. United States Department of Agriculture, październik 2001. http://dx.doi.org/10.32747/2001.7580681.bard.

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Preferential flow appears to be the rule rather than the exception in field soils and should be considered in the quantitative description of solute transport in the unsaturated zone of heterogeneous formations on the field scale. This study focused on both experimental monitoring and computer simulations to identify important features of preferential flow in the natural environment. The specific objectives of this research were: (1) To conduct dye tracing and multiple tracer experiments on undisturbed field plots to reveal information about the flow velocity, spatial prevalence, and time evolution of a preferential flow event; (2) To conduct numerical experiments to determine (i) whether preferential flow observations are consistent with the Richards flow equation; and (ii) whether volume averaging over a domain experiencing preferential flow is possible; (3) To develop a stochastic or a transfer function model that incorporates preferential flow. Regarding our field work, we succeeded to develop a new method for detecting flow patterns faithfully representing the movement of water flow paths in structured and non-structured soils. The method which is based on application of ammonium carbonate was tested in a laboratory study. Its use to detect preferential flow was also illustrated in a field experiment. It was shown that ammonium carbonate is a more conservative tracer of the water front than the popular Brilliant Blue. In our detailed field experiments we also succeeded to document the occurrence of preferential flow during soil water redistribution following the cessation of precipitation in several structureless field soils. Symptoms of the unstable flow observed included vertical fingers 20 - 60 cm wide, isolated patches, and highly concentrated areas of the tracers in the transmission zone. Soil moisture and tracer measurements revealed that the redistribution flow became fingered following a reversal of matric potential gradient within the wetted area. Regarding our simulation work, we succeeded to develop, implement and test a finite- difference, numerical scheme for solving the equations governing flow and transport in three-dimensional, heterogeneous, bimodal, flow domains with highly contrasting soil materials. Results of our simulations demonstrated that under steady-state flow conditions, the embedded clay lenses (with very low conductivity) in bimodal formations may induce preferential flow, and, consequently, may enhance considerably both the solute spreading and the skewing of the solute breakthrough curves. On the other hand, under transient flow conditions associated with substantial redistribution periods with diminishing water saturation, the effect of the embedded clay lenses on the flow and the transport might diminish substantially. Regarding our stochastic modeling effort, we succeeded to develop a theoretical framework for flow and transport in bimodal, heterogeneous, unsaturated formations, based on a stochastic continuum presentation of the flow and a general Lagrangian description of the transport. Results of our analysis show that, generally, a bimodal distribution of the formation properties, characterized by a relatively complex spatial correlation structure, contributes to the variability in water velocity and, consequently, may considerably enhance solute spreading. This applies especially in formations in which: (i) the correlation length scales and the variances of the soil properties associated with the embedded soil are much larger than those of the background soil; (ii) the contrast between mean properties of the two subdomains is large; (iii) mean water saturation is relatively small; and (iv) the volume fraction of the flow domain occupied by the embedded soil is relatively large.
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