Browsing by Author "Kim, Y"

Now showing 1 - 4 of 4
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    Constructal design of gas-cooled electric power generators, self-pumping and atmospheric circulation
    (International Journal of Heat and Mass Transfer, 2015-08-24) Bejan, A; Lorente, S; Lee, J; Kim, Y
    © 2015 Elsevier Ltd. All rights reserved. Rotating electric machines generate heat volumetrically, and are cooled by forced convection aided by the self-pumping effect. In this paper we focus on the fundamental relationship between the internal flow architecture of the gas cooled winding and its thermal performance, which is represented by the nearly uniform distribution of peak temperature throughout the winding volume. We show that the cooling passages can be sized such that the volumetric cooling is most effective. From this finding follows the number of passages and their distribution through the heat generating volume. The principle is developed analytically, and it is then validated based on numerical simulations of the cooling architecture. The paper also reports the thermodynamics basis of the self-pumping effect, and its natural occurrence as free convection in general, which includes atmospheric circulation.
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    Data set for "Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Application to the detection of residual disease in tumor margins"
    (2013-03-12) Mueller, J; Harmany, Z; Mito, J; Kennedy, S; Kim, Y; Dodd, L; Geradts, J; Kirsch, D; Willett, R; Brown, JQ; Ramanujam, N
    This is data that is published in the article "Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Application to the detection of residual disease in tumor margins".
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    Data set for "Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Application to the detection of residual disease in tumor margins"
    (2013-03-12) Brown, JQ; Dodd, L; Geradts, J; Harmany, Z; Kennedy, S; Kim, Y; Kirsch, David Guy; Mito, Jeffrey; Mueller, J; Ramanujam, Nimmi; Willett, Rebecca
    This is data that is published in the article "Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Application to the detection of residual disease in tumor margins".
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    The evolutionary design of condensers
    (Journal of Applied Physics, 2015-01-01) Bejan, A; Lee, J; Lorente, S; Kim, Y
    © 2015 AIP Publishing LLC. Condensers are flow architectures needed to provide high rates of condensation (or cooling) per unit volume, in enclosures with fixed volume. Their design has not changed from configurations consisting of the banks of horizontal tubes. In this paper, we outline a free path to evolving the design by exploring new features of flow configuration: flattened tubes, multiple tube sizes, arrays of flattened tubes, vertical tubes with turbulent film flow, forced convection condensation instead of gravity driven condensation, and the optimal length of a horizontal tube, i.e., the number of tubes in a column aligned with vapor cross flow. We show that the condensation density can be increased sizably by varying freely and without bias the morphology of the flow system: the shapes and arrangement of the cooled surfaces on which condensation occurs. The evolution of technology is described in terms of the special time direction of the useful (purposeful) changes in the configuration (shapes, arrangements) of surfaces on which flow/condensation occurs. This explains what "evolution" means. It is an important step for physics, not just technology.