Sökning: "void fraction"
Visar resultat 1 - 5 av 25 avhandlingar innehållade orden void fraction.
1. Plasticity Driven Damage and Void Growth
Sammanfattning : Plasticity induced damage evolution is considered using a thermodynamical approach. Different postulates on how to include the effects of damage in the constitutive equations have been studied. The results reveal that a mapping, similar to that of the stress, of both the kinematic and isotropic hardening variables is to be preferred. LÄS MER
2. Novel Diagnostics and Computational Methods of Neutron Fluxes in Boiling Water Reactors
Sammanfattning : The focus in this thesis is to improve knowledge of the BWR related uncertainties void, channel bow, and control rods. The presence of void determines the moderation of neutrons in BWRs. A high void fraction is less efficient in moderating neutrons than a low one. LÄS MER
3. Aspects of Sorption Processes in Thermosiphon and in Falling Film Arrangements
Sammanfattning : A study concerning closure relations pertinent to the design of sorption equipment of absorption heat pumps has been undertaken. Specifically, thermosiphon and vertical falling film arrangements were studied. LÄS MER
4. Noise Applications in Light Water Reactors with Traveling Perturbations
Sammanfattning : Neutron noise induced by perturbations traveling with the coolant of light water reactors (LWRs) is investigated. Different methods to simulate the effect of propagating perturbations are considered. The studies are performed in both open- and closed-loop systems and summarized in three chapters. LÄS MER
5. Uncertainty and Sensitivity Analysis Applied to the Validation of BWR Bundle Thermal-Hydraulic Calculations
Sammanfattning : In recent years, more realistic safety analyses of nuclear reactors have been based on best estimate (BE) computercodes. The need to validate and refine BE codes that are used in the predictions of relevant reactor safetyparameters, led to the organization of international benchmarks based on high quality experimental data. LÄS MER