High fidelity simulations in support to assess and improve RANS for modeling turbulent heat transfer in liquid metals: The case of forced convection

In the framework of accelerator driven sub-critical reactor systems (ADS), heavy liquid metals (HLM), in particular lead or lead bismuth eutectic (LBE), are considered as coolant for the reactor core and the spallation target due to their efficient heat removal properties and high production rate of neutrons. LBE-flows are characterized by excellent heat conductivity and exhibit a low molecular Prandtl number of the order 10−2 leading to distinct thermal and viscous boundary layers and scale separation in both the time and spatial domain. Since the analogy of turbulent heat and momentum transfer is employed in common turbulence models but is not valid in HLM flows, commercially available fluid dynamic code systems cannot predict heat transfer adequately for such flows. In order to provide validation data and heat transfer correlations, a series of three major experiments has been launched at the KArlsruhe Liquid metal LAboratory (KALLA) of the Karlsruhe Institute of Technology and will be presented in this overview.

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Laminar and turbulent heat transfer in the pipe entrance region for liquid metals

International Journal of Heat and Mass Transfer ◽

10.1016/0017-9310(81)90167-8 ◽

1981 ◽

Vol 24 (7) ◽

pp. 1179-1189 ◽

Cited By ~ 32

Author(s):

Chen Ching-Jen ◽

Jenq Shing Chiou

Keyword(s):

Heat Transfer ◽

Liquid Metals ◽

Entrance Region ◽

Turbulent Heat Transfer ◽

Turbulent Heat

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Turbulent Heat Transfer in a Revolving Square-Sectioned Tube

Journal of Mechanical Engineering Science ◽

10.1243/jmes_jour_1980_022_020_02 ◽

1980 ◽

Vol 22 (2) ◽

pp. 95-101 ◽

Cited By ~ 13

Author(s):

W. D. Morris ◽

F. M. Dias

Keyword(s):

Heat Transfer ◽

Forced Convection ◽

Convection Heat Transfer ◽

Turbulent Heat Transfer ◽

Electrical Machine ◽

Turbulent Heat ◽

Convection Heat ◽

Forced Convection Heat Transfer ◽

Parallel Axis ◽

Correlating Equation

An investigation of turbulent heat transfer in a revolving square-sectioned tube is reported in this paper. It is demonstrated that rotation about a parallel axis enhances the customary forced convection heat transfer, and a correlating equation for assessing this effect is proposed. The range of parameters covered in the experiments permit the results to have application for the assessment of heat transfer in certain gas-cooled electrical machine rotors.

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Forced Convection Air Cooling of Simulated Low Profile Electronic Components: Part 1—Base Case

Journal of Electronic Packaging ◽

10.1115/1.2905361 ◽

1991 ◽

Vol 113 (1) ◽

pp. 21-26 ◽

Cited By ~ 26

Author(s):

G. L. Lehmann ◽

J. Pembroke

Keyword(s):

Heat Transfer ◽

Forced Convection ◽

Flow Rate ◽

Turbulent Heat Transfer ◽

Base Case ◽

Air Cooling ◽

Turbulent Heat ◽

Electronic Components ◽

Channel Spacing ◽

Low Profile

Forced convection cooling of a simulated array of card-mounted electronic components has been investigated. An important feature of the simulated components is their relatively low profile (height/length = 0.058). Laboratory measurements of heat transfer rates resulting from convective air flow through a low aspect ratio channel are reported. The effect of variations in array position, channel spacing and flow rate is discussed. In the flow range considered laminar, transitional and turbulent heat transfer behavior have been observed. The behavior due to variations in flow rate and channel spacing is well correlated using a Reynolds number based on component length.

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