Reference EPFL-ARTICLE-147393doi:10.1115/1.2955990View record in Web of Science Record created on 2010-03-19, modified on 2017-05-10

Two-Phase Flow Patterns and Flow-Pattern Maps: Fundamentals and Applications

Experiments are performed to understand the effects of surface orientation on the pool boiling characteristics of a highly wetting fluid from a flush-mounted, micro-porous-enhanced square heater Micro-porous enhancement was achieved by applying copper and aluminum particle coatings to the heater surfaces Effects of heater orientation on CHF and nucleate boiling heat transfer for uncoated and coated surfaces are compared A correlation is developed to predict the heater orientation effect on CHF for those surfaces

Heater orientation effects on pool boiling of micro-porous-enhanced surfaces in saturated FC-72

Rough surfaces with enhanced heat transfer for electronics cooling by direct metal laser sintering

Boiling heat transfer in a hydrofoil-based micro pin fin heat sink

Optimal distribution of discrete heat sources on a plate with laminar forced convection

Hydrodynamics of two-phase flow in vertical up and down-flow across a horizontal tube bundle

Experiments have been performed using water to determine the single-phase forced convection heat transfer from in-line four simulated electronic chips, which are flush-mounted to one wall of a vertical rectangular channel. The effects of the most influential geometric parameters on heat transfer including chip number, and channel height are tested. The channel height is varied over values of 0.5, 0.7, and 1.0 times the heat source length. The heat flux is set at the three values of 5 W/cm2 , 10 W/cm2 , and 20 W/cm2 , and the Reynolds number based on the heat source length ranges from 6 × 102 to 8 × 104 . Transition Reynolds numbers are deduced from the heat transfer data. The experimental results indicate that the heat transfer coefficient is affected strongly by the number of chips and the Reynolds number and weakly by the channel height. Finally, the present results from liquid-cooling are compared with other results from air-cooling, and Prandtl number scaling between air and water is investigated.

An Experimental Study on Forced Convection Heat Transfer From Flush-Mounted Discrete Heat Sources

Effects of rotation on natural convection cooling from three rows of heat sources in a rectangular cavity

Void fraction and friction pressure drop measurements were made for an adiabatic, horizontal two-phase flow of air-water, air-oil across a horizontal in-line, 5 × 20 tube bundle with pitch-to-diameter ratio, P/D, of 1.28. For both air-water and air-oil flow, the experimental results showed that the average void fraction were less than the values predicted by a homogenous flow model, but were well correlated with the Martinelli parameter X tt and liquid-only Froude number Fr LO . The two-phase friction multiplier data exhibited an effect of flow pattern and mass velocity, and they could be well-correlated with the Martinelli parameter.

Two-Phase Void Fraction and Pressure Drop in Horizontal Crossflow Across a Tube Bundle

Experimental studies of single-phase heat transfer with the working fluid FC-72 from a single chip and a four-in-line chip module mounted on one wall of a vertical rectangular channel are carried out. Both flush-mounted and protruding chip configurations are investigated with the channel height being equal to the ship length. The Reynolds number based on chip length ranged from 2.2 × 103 to 6.3 × 104 (3.0 × 103 < ReD < 8.4 × 104) for an inlet temperature of 25°C. Results for a single flush-mounted chip are in good agreement with those obtained for the most upstream chip of the multichip module. Heat transfer data of a single heated protruding chip located downstream agree well with the results from the single flush-mounted chip. Heat transfer coefficients from flush-mounted chips are less than those from protruding chips.

K. W. Tou

Papers

Hydrodynamics of two-phase flow in vertical up and down-flow across a horizontal tube bundle

An Experimental Study on Forced Convection Heat Transfer From Flush-Mounted Discrete Heat Sources

Effects of rotation on natural convection cooling from three rows of heat sources in a rectangular cavity

Two-Phase Void Fraction and Pressure Drop in Horizontal Crossflow Across a Tube Bundle

Direct liquid cooling of electronic chips by single-phase forced convection of fc-72