The Experts below are selected from a list of 57720 Experts worldwide ranked by ideXlab platform
Mingzhen Wei - One of the best experts on this subject based on the ideXlab platform.
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Decoupling the Stationary Navier-Stokes-Darcy System with the Beavers-Joseph-Saffman Interface Condition
Abstract and Applied Analysis, 2013Co-Authors: Yong Cao, Yuchuan Chu, Mingzhen WeiAbstract:This paper proposes a domain decomposition method for the coupled stationary Navier-Stokes and Darcy equations with the Beavers-Joseph-Saffman Interface Condition in order to improve the efficiency of the finite element method. The physical Interface Conditions are directly utilized to construct the boundary Conditions on the Interface and then decouple the Navier-Stokes and Darcy equations. Newton iteration will be used to deal with the nonlinear systems. Numerical results are presented to illustrate the features of the proposed method.
Hyungyu Jin - One of the best experts on this subject based on the ideXlab platform.
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enhancing the spin seebeck effect by controlling Interface Condition in pt polycrystalline nickel ferrite slabs
Journal of Applied Physics, 2020Co-Authors: Minyoung Kim, Sang J Park, Hyungyu JinAbstract:The spin Seebeck effect (SSE) is an emergent thermoelectric phenomenon, which enables a thermal-to-electrical energy conversion via the thermal injection of spin currents from a ferromagnet (FM) into an attached paramagnetic metal (PM). Recent studies have revealed that the SSE is very sensitive to the PM/FM Interface Condition, suggesting a potential way to enhance the SSE by controlling the Interface Condition. However, most of the previous studies are limited to conventional Pt/bulk single-crystal or thin-film YIG systems, lacking consideration for mesoscale surface defects such as pores and grain grooves, which frequently exist in more prevalent bulk polycrystalline magnets. Here, we investigate the effect of Interface Condition on the longitudinal SSE (LSSE) in a Pt/polycrystalline NiFe2O4 (NFO) slab system. Different Interface Conditions are induced by treating the surface of NFO slabs with varying combinations of polishing force (Fp) and post-annealing temperature (Ta) before the Pt deposition. The resultant LSSE signals show strong correlations with different Interface parameters. In particular, we find that mesoscale surface defects (cracks, pores, and grain grooves) and the surface roughness play a crucial role in determining the magnitude of LSSE signals and demonstrate that those parameters can be deliberately controlled by properly choosing Fp and Ta. We report one sample with a spin Seebeck coefficient of 0.58 μV/K, which is significantly larger than that of bulk polycrystalline magnets reported thus far.
Long Chen - One of the best experts on this subject based on the ideXlab platform.
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a divergence free weak virtual element method for the stokes darcy problem on general meshes
Computer Methods in Applied Mechanics and Engineering, 2019Co-Authors: Gang Wang, Feng Wang, Long ChenAbstract:Abstract This paper presents a weak virtual element method on general meshes for the Stokes–Darcy problem with the Beavers–Joseph–Saffman Interface Condition. The velocity is discretized by the H ( div ) virtual element. The pressure is approximated by discontinuous piecewise polynomials. Besides, a polynomial space on the element faces is introduced to approximate the tangential trace of the velocity in the Stokes equations. The velocity on the discrete level is exactly divergence free and thus the exact mass conservation is preserved in the discretization. The well-posedness of the discrete problem is proved and an a priori error estimate is derived that implies the error for the velocity in a suitable norm does not depend on the pressure. A series of numerical experiments are reported to illustrate the performance of the method.
Yong Cao - One of the best experts on this subject based on the ideXlab platform.
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Decoupling the Stationary Navier-Stokes-Darcy System with the Beavers-Joseph-Saffman Interface Condition
Abstract and Applied Analysis, 2013Co-Authors: Yong Cao, Yuchuan Chu, Mingzhen WeiAbstract:This paper proposes a domain decomposition method for the coupled stationary Navier-Stokes and Darcy equations with the Beavers-Joseph-Saffman Interface Condition in order to improve the efficiency of the finite element method. The physical Interface Conditions are directly utilized to construct the boundary Conditions on the Interface and then decouple the Navier-Stokes and Darcy equations. Newton iteration will be used to deal with the nonlinear systems. Numerical results are presented to illustrate the features of the proposed method.
Minyoung Kim - One of the best experts on this subject based on the ideXlab platform.
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enhancing the spin seebeck effect by controlling Interface Condition in pt polycrystalline nickel ferrite slabs
Journal of Applied Physics, 2020Co-Authors: Minyoung Kim, Sang J Park, Hyungyu JinAbstract:The spin Seebeck effect (SSE) is an emergent thermoelectric phenomenon, which enables a thermal-to-electrical energy conversion via the thermal injection of spin currents from a ferromagnet (FM) into an attached paramagnetic metal (PM). Recent studies have revealed that the SSE is very sensitive to the PM/FM Interface Condition, suggesting a potential way to enhance the SSE by controlling the Interface Condition. However, most of the previous studies are limited to conventional Pt/bulk single-crystal or thin-film YIG systems, lacking consideration for mesoscale surface defects such as pores and grain grooves, which frequently exist in more prevalent bulk polycrystalline magnets. Here, we investigate the effect of Interface Condition on the longitudinal SSE (LSSE) in a Pt/polycrystalline NiFe2O4 (NFO) slab system. Different Interface Conditions are induced by treating the surface of NFO slabs with varying combinations of polishing force (Fp) and post-annealing temperature (Ta) before the Pt deposition. The resultant LSSE signals show strong correlations with different Interface parameters. In particular, we find that mesoscale surface defects (cracks, pores, and grain grooves) and the surface roughness play a crucial role in determining the magnitude of LSSE signals and demonstrate that those parameters can be deliberately controlled by properly choosing Fp and Ta. We report one sample with a spin Seebeck coefficient of 0.58 μV/K, which is significantly larger than that of bulk polycrystalline magnets reported thus far.