The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform
Shigeho Noda - One of the best experts on this subject based on the ideXlab platform.
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Numerical simulation of Natural Convection with density inversion in a square cavity
Numerical Heat Transfer Part A: Applications, 2000Co-Authors: Masaaki Ishikawa, Tetsuo Hirata, Shigeho NodaAbstract:Water has its density maximum at 4oC, and Natural Convection around the temperature is complicated. In this study, Natural Convection with density inversion in a two-dimensional vertical square cav...
Huimin Cui - One of the best experts on this subject based on the ideXlab platform.
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A three-dimensional simulation of transient Natural Convection in a triangular cavity
International Journal of Heat and Mass Transfer, 2015Co-Authors: Huimin Cui, Suvash C. SahaAbstract:Abstract The three-dimensional (3D) numerical simulation of Natural Convection in a triangular cavity with the top cooling and the bottom heating is performed and compared with the previous experiment. The numerical results show that the development of Natural Convection in the cavity following an initially isothermal and stationary state may be classified into three stages: an initial stage, a transitional stage and a quasi-steady stage, which is consistent with the experimental result. Natural Convection flows in each of the stages, particularly the 3D flow structure such as longitudinal rolls, are described. Further, the regimes of transient Natural Convection are discussed using a simple scaling analysis and the scaling relations obtained are validated by the present numerical results.
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Natural Convection in a differentially heated cavity
Advances in Mechanics, 2014Co-Authors: Huimin CuiAbstract:The study of Natural Convection in a differentially heated cavity is of practical significance in nature and industry. It is of scientific value to review the studies of Natural Convection flows, their flow properties, dynamical mechanisms, dimensional controlling parameter dependencies and heat transfer driven by the horizontal temperature gradient in the cavity. As shown by previous studies, the development of Natural Convection suddenly enforced by the horizontal temperature gradient between the sidewalls of the cavity includes an initial stage, a transitional stage and a steady or a quasi-steady stage. The transient flows in the different stages are determined by the Rayleigh number, the Prandtl number and the aspect ratio. The flow in the steady or quasi-steady stage could be a steady laminar, a periodic or a turbulent flow. In addition, the studies of instability and turbulence of Natural Convection in the cavity are reviewed, and the prospects for the study of Natural Convection in the cavity are presented.
Masaaki Ishikawa - One of the best experts on this subject based on the ideXlab platform.
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Numerical simulation of Natural Convection with density inversion in a square cavity
Numerical Heat Transfer Part A: Applications, 2000Co-Authors: Masaaki Ishikawa, Tetsuo Hirata, Shigeho NodaAbstract:Water has its density maximum at 4oC, and Natural Convection around the temperature is complicated. In this study, Natural Convection with density inversion in a two-dimensional vertical square cav...
Ole Sigmund - One of the best experts on this subject based on the ideXlab platform.
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topology optimisation for Natural Convection problems
International Journal for Numerical Methods in Fluids, 2014Co-Authors: Joe Alexandersen, Casper Schousboe Andreasen, Niels Aage, Ole SigmundAbstract:This paper demonstrates the application of the density-based topology optimisation approach for the design of heat sinks and micropumps based on Natural Convection effects. The problems are modelled under the assumptions of steady-state laminar flow using the incompressible Navier-Stokes equations coupled to the Convection-diffusion equation through the Boussinesq approximation. In order to facilitate topology optimisation, the Brinkman approach is taken to penalise velocities inside the solid domain and the effective thermal conductivity is interpolated in order to accommodate differences in thermal conductivity of the solid and fluid phases. The governing equations are discretised using stabilised finite elements and topology optimisation is performed for two different problems using discrete adjoint sensitivity analysis. The study shows that topology optimisation is a viable approach for designing heat sink geometries cooled by Natural Convection and micropumps powered by Natural Convection. Copyright c © 2013 John Wiley & Sons, Ltd.
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Topology optimisation for Natural Convection problems
International Journal for Numerical Methods in Fluids, 2014Co-Authors: Joe Alexandersen, Casper Schousboe Andreasen, Niels Aage, Ole SigmundAbstract:This paper demonstrates the application of the density-based topology optimisation approach for the design of heat sinks and micropumps based on Natural Convection effects. The problems are modelled under the assumptions of steady-state laminar flow using the incompressible Navier-Stokes equations coupled to the Convection-diffusion equation through the Boussinesq approximation. In order to facilitate topology optimisation, the Brinkman approach is taken to penalise velocities inside the solid domain and the effective thermal conductivity is interpolated in order to accommodate differences in thermal conductivity of the solid and fluid phases. The governing equations are discretised using stabilised finite elements and topology optimisation is performed for two different problems using discrete adjoint sensitivity analysis. The study shows that topology optimisation is a viable approach for designing heat sink geometries cooled by Natural Convection and micropumps powered by Natural Convection.
Suvash C. Saha - One of the best experts on this subject based on the ideXlab platform.
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Natural Convection and heat transfer on a section-triangular roof
International Communications in Heat and Mass Transfer, 2018Co-Authors: Haoyu Zhai, Suvash C. Saha, Yudong HouAbstract:Abstract Natural Convection and heat transfer on a section-triangular roof are common around buildings. In this study, the slope flow and the plume on the suddenly heated section-triangular roof are investigated using scaling analysis and numerical simulation. The dynamics and heat transfer are discussed. It has been demonstrated that there exist different regimes of transient Natural Convection on the roof, which depends on the Rayleigh number, the aspect ratio of the roof and the Prandtl number. The scaling laws in different scenarios including inertial and viscous regimes are obtained and verified by numerical results. There is agreement between the scaling laws and numerical results. Further, the formulae of heat transfer and Natural Convection on the roof are presented.
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A three-dimensional simulation of transient Natural Convection in a triangular cavity
International Journal of Heat and Mass Transfer, 2015Co-Authors: Huimin Cui, Suvash C. SahaAbstract:Abstract The three-dimensional (3D) numerical simulation of Natural Convection in a triangular cavity with the top cooling and the bottom heating is performed and compared with the previous experiment. The numerical results show that the development of Natural Convection in the cavity following an initially isothermal and stationary state may be classified into three stages: an initial stage, a transitional stage and a quasi-steady stage, which is consistent with the experimental result. Natural Convection flows in each of the stages, particularly the 3D flow structure such as longitudinal rolls, are described. Further, the regimes of transient Natural Convection are discussed using a simple scaling analysis and the scaling relations obtained are validated by the present numerical results.
