Category Archives: Thoria-based Nuclear Fuels

UO2

The melting point of UO2 given in MATPRO [28] is 3,113.15 K. This temperature is based on the measurement made by Brassfield et al. [29] and the equations for the solids and liquids boundaries of the UO2-PuO2 phase diagram given by Lyon and Bailey [30]. The recommended values by ORNL [31] for UO200 are

Read more

Thermal Conductivity of ThO2

The thermal conductivity of ThO2 up to 1,800 K is reasonably well established (Table 12). Most of the data were derived from thermal diffusivity measurements. Peterson and Curtis [26] compiled data on thermal conductivity of ThO2 to about 2,000 K. Bakker et al. [38] systematically evaluated the data of various authors. They analyzed the data of Pears [102], Rodriguez et […]

Read more

ThO2-UO2 System

Phase diagram studies of the ThO2-UO2 system have been reported by several authors. Lambertson et al. [21] used a quench technique, Christensen [27, 37] a tungsten filament technique, whereas Latta et al. [34] applied a thermal arrest method. The phase diagram of ThO2-UO2 can be constructed with the help of the melting points and enthalpies of fusion of the end […]

Read more

Thermal Conductivity of UO2

There are many publications numbering over hundreds dealing with thermal conductivity of UO2. Washington [116], Brandt and Neuer [117], and Fink et al. [50] made appraisals of the conductivity data found in the open literature. Brandt and Neur [117] presented a mean correlation curve of thermal conductivity versus temperature for UO2 by using data from number of sources. Their equation […]

Read more

ThO2-PuO2 System

Freshley and Mattys [41, 42] have shown that ThO2 and PuO2 form a complete solid solution (Fig. 2) in the whole composition range like ThO2 and UO2. A continuous series of solid solution has also been reported by Mulford and Ellinger [44]. They found only a single fluorite structure by X-ray diffraction (XRD) and also showed that the lattice parameter […]

Read more

Density

The fuel density, p is an important property of the fuel and is a function of the following factors: fuel composition, temperature, amount of porosity, O/M ratio, and burnup. The theoretical densities of the materials (pT) can be calculated from the knowledge of lattice type and values of lattice parameter. Assuming that the elements form a solid solution, the theoretical […]

Read more

Thermal Conductivity of ThO2-PuO2 Fuel

Although thoria-based fuels have been studied extensively in the past, namely in the 1970s, to our knowledge very little open literature is available for (Th, Pu)O2 [40, 130]. Only a few measurements of thermal conductivity have been made for ThO2-PuO2 fuel. Since CeO2 and PuO2 have similar thermodynamic and crys­tallographic properties [131], Murbayashi [114] tried to simulate the thermal conductivity […]

Read more

Density of Liquid UO2

The recommended equation for the density of liquid uranium dioxide is based on the in-pile measurements of the vapor pressure, density, and isothermal com­pressibility of liquid (U, Pu)O2 by Breitung and Reil [62]. Measurements of density as a function of enthalpy and as a function of temperature were obtained from the melting point to 7,600 K. The equation of Breitung […]

Read more
1 2 3