Thermal conductivity and diffusion mechanisms of noble gases in uranium dioxide: A DFT+U study

The Navier-Stokes equations have been used for numerical modeling of chemically reacting gas flow in the propulsion chamber. The chamber represents an axially symmetrical plane disk. Fuel and oxidant were fed into the chamber separately at some angle to the inflow surface and not parallel one to another to ensure better mixing of species. The model is based on conservation laws of mass, momentum, and energy for nonsteady two-dimensional compressible gas flow in the case of axial symmetry. The processes of viscosity, thermal conductivity, turbulence, and diffusion of species have been taken into account. The possibility of detonation mode of combustion of the mixture in the chamber was numerically demonstrated. The detonation triggering depends on the values of angles between fuel and oxidizer jets. This type of the propulsion chamber is effective because of the absence of stagnation zones and good mixing of species before burning.

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New Results on the Thermal Conductivity of the Noble Gases and of Two Binary Mixtures

Thermal Conductivity 16 ◽

10.1007/978-1-4684-4265-6_46 ◽

1983 ◽

pp. 537-547

Author(s):

Joseph Kestin ◽

Richard Fleeter ◽

W. A. Wakeham

Keyword(s):

Thermal Conductivity ◽

Binary Mixtures ◽

Noble Gases

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Li+ionic conductivities and diffusion mechanisms in Li-based imides and lithium amide

Physical Chemistry Chemical Physics ◽

10.1039/c2cp23636b ◽

2012 ◽

Vol 14 (5) ◽

pp. 1596-1606 ◽

Cited By ~ 29

Author(s):

Wen Li ◽

Guotao Wu ◽

Zhitao Xiong ◽

Yuan Ping Feng ◽

Ping Chen

Keyword(s):

Ionic Conductivities ◽

Lithium Amide ◽

Diffusion Mechanisms ◽

And Diffusion

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The effect of density on the thermal conductivity of uranium dioxide

Journal of Nuclear Materials ◽

10.1016/0022-3115(69)90127-5 ◽

1969 ◽

Vol 29 (1) ◽

pp. 67-81 ◽

Cited By ~ 23

Author(s):

R.B. Asamoto ◽

F.L. Anselin ◽

A.E. Conti

Keyword(s):

Thermal Conductivity ◽

Uranium Dioxide

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Utilization of Thorium in LWR Fuels Aiming at Thermal Conductivity Improvements

Volume 5: Student Paper Competition ◽

10.1115/icone24-60300 ◽

2016 ◽

Author(s):

Jan Kubáň ◽

Radek Škoda

Keyword(s):

Thermal Conductivity ◽

Uranium Dioxide ◽

Nuclear Power ◽

Fuel Pellet ◽

Thorium Dioxide ◽

Heterogeneous Distribution ◽

Thermal Output ◽

Homogenous Distribution ◽

Limiting Parameters ◽

Almost All

One of the main drawbacks of uranium dioxide, which is used in almost all nuclear power reactors, is its low thermal conductivity. As a consequence, temperature at the center of fuel pellet is relatively high, because heat is poorly conducted away. To reach a higher level of safety, maximal temperature in any fuel pellet is one of the main limiting parameters, which restrict the fuel thermal output. This paper deals with the use of thorium in LWR fuels with the objective of fuel pellet maximal temperature reduction. Research investigating homogenous distribution of thorium dioxide (thoria) in uranium dioxide fuel has already been done and did not lead to considerable thermal conductivity improvements. The aim of this study is to investigate heterogeneous distribution of thorium in commonly used uranium dioxide fuel in the form of uranium and thorium pellets placed together.

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