background: decrease of economically accessible uranium resources motivates consideration of breeding of fertile elements such as thorium. material and method: thorium oxide fuel burn up calculation of a simulated research reactor cooled heavy water has been proposed in the present work using mcnpx 2.6 code. two 233u and 235u isotopes have been used as fissile element of thorium oxide fuel. 135...

The Cesium (Cs-137) isotopic concentration due to irradiation of TRIGA Fuel Elements FE(s) is calculated andmeasured at the Atominstitute (ATI) of ViennaUniversity of Technology (VUT). The Cs-137 isotope, as proved burn-up indicator, was applied to determine the burn-up of the TRIGAMark II research reactor FE. This article presents the calculations andmeasurements of the Cs-137 isotope and its ...

Background: Decrease of economically accessible uranium resources motivates consideration of breeding of fertile elements such as thorium. Material and Method: Thorium oxide fuel burn up calculation of a simulated research reactor cooled heavy water has been proposed in the present work using MCNPX 2.6 code. Two 233U and 235U isotopes have been used as fissile element of thorium oxide fuel. 135...

Pebble bed reactors fuel elements are specially suited for withstanding very high burn-up values. This is one of the main characteristics of a transmutation fuel. The higher the burn-up achieved in the fuel, the smaller the number of reprocessing steps needed for obtaining a high transmutation rate. In this paper, a new transmutation cycle option will be introduced, based in a single pass of th...

This study develops a trajectory optimization algorithm for approximately minimizing aircraft travel time and fuel burn by combining a method for computing minimum-time routes in winds on multiple horizontal planes, and an aircraft fuel burn model for generating fuel-optimal vertical profiles. It is applied to assess the potential benefits of flying userpreferred routes for commercial cargo fli...

Global optimization of transport aircraft is performed to minimize fuel burn for a specified mission. The design space includes the geometry, wing airfoils, primary structure, engine size and cycle parameters, and the flight profile parameters. The method employs a number of physics-based models for structural sizing and weight estimation, viscous CFD for all major aerodynamic components, and a...

In 2004, as many as 444 nuclear energy reactors were operated in 31 countries worldwide. Most of them burn classical nuclear fuels, thus either uranium dioxide UO2 containing natural uranium, uranium enriched by U-235 or, less often, the so-called MOX (Mixed Oxide) fuel, which is a mixture of UO2 and PuO2 . The use of nuclear fuels and introduction of their novel types requires detailed knowled...

TRIGLAV code was developed for TRIGA research reactor calculations and is based on twodimensional diffusion equation. The main purpose of the program is calculation of the fuel elements burn-up. Calculated core burn-up and excess reactivity results are compared with experimental values. New control rod model is introduced and tested in this paper. Calculated integral control rod worth and calcu...