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Kaichiro Mishima

Bio: Kaichiro Mishima is an academic researcher from Kyoto University. The author has contributed to research in topics: Two-phase flow & Critical heat flux. The author has an hindex of 29, co-authored 107 publications receiving 3724 citations.


Papers
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Journal ArticleDOI
TL;DR: In this article, a two-fluid formulation for two-phase flow analyses is presented, where a fully threedimensional model is obtained from the time averaging, whereas the one-dimensional model was developed from the area averaging.

738 citations

Journal ArticleDOI
TL;DR: In this paper, the Chen correlation has been modified to be used for four flow conditions such as liquid-laminar and gas-turbulent one often occurring in mini-channels.

225 citations

Journal ArticleDOI
TL;DR: In this paper, a correlation for the amount of entrained liquid in annular flow has been developed from a simple model and experimental data, which can provide accurate information on entrainment which have not been available previously.

224 citations

Journal ArticleDOI
TL;DR: In this paper, the authors measured void fraction, slug bubble velocity, and pressure loss for rectangular ducts with a narrow gap and a large aspect ratio using the neutron radiography technique, and the void fraction was well-correlated by the drift flux model with the existing correlation for the distribution parameter.

208 citations

Journal ArticleDOI
TL;DR: In this article, the authors explored alternative correlations of two-phase friction pressure drop and void fraction for mini-channels based on the separated flow model and drift-flux model.

198 citations


Cited by
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Dissertation
01 Jan 2003
TL;DR: In this paper, the authors describe the development and validation of Computational Fluid Dynamics (CFD) methodology for the simulation of dispersed two-phase flows, which employs averaged mass and momentum conservation equations to describe the time-dependent motion of both phases.
Abstract: This study describes the development and validation of Computational Fluid Dynamics (CFD) methodology for the simulation of dispersed two-phase flows. A two-fluid (Euler-Euler) methodology previously developed at Imperial College is adapted to high phase fractions. It employs averaged mass and momentum conservation equations to describe the time-dependent motion of both phases and, due to the averaging process, requires additional models for the inter-phase momentum transfer and turbulence for closure. The continuous phase turbulence is represented using a two-equation k − ε−turbulence model which contains additional terms to account for the effects of the dispersed on the continuous phase turbulence. The Reynolds stresses of the dispersed phase are calculated by relating them to those of the continuous phase through a turbulence response function. The inter-phase momentum transfer is determined from the instantaneous forces acting on the dispersed phase, comprising drag, lift and virtual mass. These forces are phase fraction dependent and in this work revised modelling is put forward in order to capture the phase fraction dependency of drag and lift. Furthermore, a correlation for the effect of the phase fraction on the turbulence response function is proposed. The revised modelling is based on an extensive survey of the existing literature. The conservation equations are discretised using the finite-volume method and solved in a solution procedure, which is loosely based on the PISO algorithm, adapted to the solution of the two-fluid model. Special techniques are employed to ensure the stability of the procedure when the phase fraction is high or changing rapidely. Finally, assessment of the methodology is made with reference to experimental data for gas-liquid bubbly flow in a sudden enlargement of a circular pipe and in a plane mixing layer. Additionally, Direct Numerical Simulations (DNS) are performed using an interface-capturing methodology in order to gain insight into the dynamics of free rising bubbles, with a view towards use in the longer term as an aid in the development of inter-phase momentum transfer models for the two-fluid methodology. The direct numerical simulation employs the mass and momentum conservation equations in their unaveraged form and the topology of the interface between the two phases is determined as part of the solution. A novel solution procedure, similar to that used for the two-fluid model, is used for the interface-capturing methodology, which allows calculation of air bubbles in water. Two situations are investigated: bubbles rising in a stagnant liquid and in a shear flow. Again, experimental data are used to verify the computational results.

968 citations

Journal ArticleDOI
TL;DR: In this article, the authors measured air-water flows in capillary tubes with inner diameters in the range from 1 to 4 mm and found that the boundary between flow regimes was predicted well by Mishima-Ishii's model.

898 citations

Journal ArticleDOI
Issam Mudawar1
TL;DR: This paper explores the recent research developments in high-heat-flux thermal management and demonstrates that, while different cooling options can be tailored to the specific needs of individual applications, system considerations always play a paramount role in determining the most suitable cooling scheme.
Abstract: This paper explores the recent research developments in high-heat-flux thermal management. Cooling schemes such as pool boiling, detachable heat sinks, channel flow boiling, microchannel and mini-channel heat sinks, jet-impingement, and sprays, are discussed and compared relative to heat dissipation potential, reliability, and packaging concerns. It is demonstrated that, while different cooling options can be tailored to the specific needs of individual applications, system considerations always play a paramount role in determining the most suitable cooling scheme. It is also shown that extensive fundamental electronic cooling knowledge has been amassed over the past two decades. Yet there is now a growing need for hardware innovations rather than perturbations to those fundamental studies. An example of these innovations is the cooling of military avionics, where research findings from the electronic cooling literature have made possible the development of a new generation of cooling hardware which promise order of magnitude increases in heat dissipation compared to today's cutting edge avionics cooling schemes.

824 citations

Journal ArticleDOI
TL;DR: In this article, the kinematic constitutive equation for the drift velocity has been studied for various two-phase flow regimes, and a comparison of the model with various experimental data over various flow regimes and a wide range of flow parameters shows a satisfactory agreement.

799 citations

31 Dec 1996
TL;DR: In this paper, the authors focus on the derivation and closing of the model equations, and the validity of the mixture model is also carefully analyzed, starting from the continuity and momentum equations written for each phase in a multiphase system, the field equations for the mixture are derived.
Abstract: Numerical flow simulation utilising a full multiphase model is impractical for a suspension possessing wide distributions in the particle size or density. Various approximations are usually made to simplify the computational task. In the simplest approach, the suspension is represented by a homogeneous single-phase system and the influence of the particles is taken into account in the values of the physical properties. This study concentrates on the derivation and closing of the model equations. The validity of the mixture model is also carefully analysed. Starting from the continuity and momentum equations written for each phase in a multiphase system, the field equations for the mixture are derived. The mixture equations largely resemble those for a single-phase flow but are represented in terms of the mixture density and velocity. The volume fraction for each dispersed phase is solved from a phase continuity equation. Various approaches applied in closing the mixture model equations are reviewed. An algebraic equation is derived for the velocity of a dispersed phase relative to the continuous phase. Simplifications made in calculating the relative velocity restrict the applicability of the mixture model to cases in which the particles reach the terminal velocity in a short time period compared to the characteristic time scale of the flow of the mixture. (75 refs.)

758 citations