Journal ArticleDOI
Single-Phase Heat Transfer and Fluid Flow in Micropipes
TLDR
In this paper, the authors provide a general overview of single-phase heat transfer and flow in capillary (micro) pipes, and analyze the Laminar-to-Turbulent flow transition in detail.Abstract:
The objective of this paper is to provide a general overview of the research carried out so far in single-phase heat transfer and flow in capillary (micro) pipes. Laminar flow and laminar-to-turbulent flow transition are analyzed in detail in order to clarify the discrepancies among the results obtained by different researchers. Experiments performed in the ENEA laboratory indicate that in laminar flow regime, the friction factor is in good agreement with the Hagen-Poiseuille theory for a Reynolds number below 600–800. For higher values of the Reynolds number, experimental data depart from the Hagen-Poiseuille law to the side of higher f values. The transition from laminar-to-turbulent flow occurs for Reynolds number in the range 1800–2500. Heat transfer experiments show that heat transfer correlations in laminar and turbulent regimes, developed for conventional (macro) tubes, are not properly adequate for heat transfer rate prediction in microtubes.read more
Citations
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Book ChapterDOI
Boundary Layer Theory
TL;DR: The boundary layer equations for plane, incompressible, and steady flow are described in this paper, where the boundary layer equation for plane incompressibility is defined in terms of boundary layers.
Journal ArticleDOI
Characterization of fluid dynamic behaviour and channel wall effects in microtube
TL;DR: In this article, the influence of channel wall roughness and channel wall hydrophobicity on adiabatic flow in circular microchannels is investigated, varying in diameter from 70μm to 326μm.
Journal ArticleDOI
Bubble confinement in flow boiling of FC-72 in a "rectangular" microchannel of high aspect ratio
TL;DR: In this article, a transparent, metallic, conductive deposit has been developed on the exterior of the rectangular microchannel, allowing simultaneous uniform heating and visualisation to be achieved, and sensitive pressure sensors are used to record the pressure drop across the microchannel over time.
Journal ArticleDOI
Convective heat transfer in liquid microchannels with hydrophobic and hydrophilic surfaces
Shou-Shing Hsieh,Chih-Yi Lin +1 more
TL;DR: In this paper, the heat transfer characteristics of channel flows of deionized (DI) water, methanol, 50-wt% DI water/50-wwt% methenol mixture, and ethanol solution in asymmetrically heated rectangular microchannels with an aspect ratio (H/W) of 0.56 and the corresponding hydraulic diameters (D ) of 129 μm at 5.
Heat Transfer in Microchannels.
TL;DR: In this article, an analytical expression for the velocity distribution with slip-flow was obtained which involved the Knudsen number Kn in an infinite series form, and the experimental results show that the method is effective.
References
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Book
Boundary layer theory
TL;DR: The flow laws of the actual flows at high Reynolds numbers differ considerably from those of the laminar flows treated in the preceding part, denoted as turbulence as discussed by the authors, and the actual flow is very different from that of the Poiseuille flow.
Book
Experimental methods for engineers
TL;DR: In this paper, the authors present basic concepts and analysis of experimental data for basic electrical measurements and sensors, including Displacement and Area Measurements, Pressure Measurement, Flow Measurement and Temperature Measurement.
Book ChapterDOI
Boundary Layer Theory
TL;DR: The boundary layer equations for plane, incompressible, and steady flow are described in this paper, where the boundary layer equation for plane incompressibility is defined in terms of boundary layers.