Showing papers by "Suhas V. Patankar published in 1996"
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TL;DR: In this paper, a finite-volume method for radiative transfer in cylindrical enclosures is presented, where angular redistribution terms in the equation of transfer are avoided by defining radiation directions in terms of angular coordinates measured with respect to Cartesian base vectors; this definition of radiation directions can result in control angles that overlap control volume faces, depending on the type of spatial and angular grids used in the azimuthal direction.
Abstract: A finite-volume method for radiative transfer in cylindrical enclosures is presented. Angular redistribution terms in the equation of transfer are avoided by defining radiation directions in terms of angular coordinates measured with respect to Cartesian base vectors; this definition of radiation directions can result in control angles that overlap controlvolume faces, depending on the type of spatial and angular grids used in the azimuthal direction. A simple treatment far such control-angle overlaps is presented, which is also applicable to nonorthogonal curvilinear spatial coordinates. A comparison of the present procedure with other similar methods is given. Solutions are presented for axisymmetric transfer through a cylinder and nonaxisymmetric transfer through two- and three-dimensional annular sectors. Results show that the procedure produces reasonable solutions for transparent and participating media in axisymmetric and nonaxisymmetric cylindrical enclosures.
42 citations
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31 citations
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TL;DR: A simple non-gray gas model for use in radiation computations is proposed in this paper, which is based on the idea of k distribution, or reordering the highly irregular variation of absorption coefficient to obtain a smooth function.
Abstract: A simple non-gray gas model for use in radiation computations is proposed. This is based on the idea of k distribution, or reordering the highly irregular variation of absorption coefficient to obtain a smooth function. In the present approach, a methodology to obtain the reordered distribution from a wide-band model is presented, which is simpler than previous methods. Several test problems, including nonisothermal and inhomogeneous media, are solved using the model. The validity of the approach is tested by comparing solutions to radiation problems with previously published results.
25 citations
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TL;DR: The overall performance, in terms of CPU times for a prescribed accuracy, of the proposed calculation procedure is compared with that of a conventional single-grid method based on the power-law differencing scheme and the SIMPLER algorithm.
Abstract: This article reports the performance of the block-correction-based coupled multigrid method in conjunction with an improved discretization scheme for the solution of three-dimensional fluid flow problems. Laminar flow in a cubic cavity with a moving wall is calculated for different Reynolds numbers. The performance of the multigrid method is compared with that of a single-grid method based on the SIMPLER algorithm. To highlight the combined advantage of the improved discretization scheme and the multigrid method, the overall performance, in terms of CPU times for a prescribed accuracy, of the proposed calculation procedure is also compared with that of a conventional single-grid method based on the power-law differencing scheme and the SIMPLER algorithm.
12 citations
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TL;DR: In this article, a numerical study on the transient heating of a cast iron slab in a car-hearth furnace is presented, where the influence of the direction of jets issuing from the burners on the velocity and temperature fields during the heating period was investigated.
Abstract: A numerical study on the transient heating of a cast iron slab in a car-hearth furnace is presented. The influence of the direction of jets issuing from the burners on the velocity and temperature fields during the heating period was investigated. The standard k-e turbulence model is used in the present study. It is found that the direction of the jets has a significant influence on the temperature distribution in the slab. It is also shown that inclined jets produce a more uniform temperature field and that the time needed for the slab to reach a predetermined temperature can be significantly reduced which results in the reduction of energy consumption.