Sökning: "Staffan Jacobsson Svärd"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden Staffan Jacobsson Svärd.

1. 1. A Tomographic Measurement Technique for Irradiated Nuclear Fuel Assemblies

   Författare :Staffan Jacobsson Svärd; Anders Bäcklin; Ane Håkansson; Klaas van der Meer; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; tomography; nuclear fuel; SPECT; core physics; validation; pin power; safeguards; partial-defect verification; Kärnfysik; Nuclear physics; Kärnfysik;

   Sammanfattning : The fuel assemblies used at the Swedish nuclear power plants contain typically between 100 and 300 fuel rods. An experimental technique has been demanded for determining the relative activities of specific isotopes in individual fuel rods without dismantling the assemblies. LÄS MER

3. 2. Fast-Neutron Tomography using a Mobile Neutron Generator for Assessment of Steam-Water Distributions in Two-Phase Flows

   Författare :Peter Andersson; Staffan Jacobsson Svärd; Henrik Sjöstrand; Stephan Pomp; Ane Håkansson; Michael Österlund; Bernhard Ludewigt; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Void distribution; neutron tomography; plastic scintillator; transmission measurements; neutron detection; Applied Nuclear Physics; Tillämpad kärnfysik;

   Sammanfattning : This thesis describes the measurement technique of fast-neutron tomography for assessing spatial distributions of steam and water in two-phase flows. This so-called void distribution is of importance both for safe operation and for efficient use of the fuel in light water reactors, which compose the majority of the world’s commercial nuclear reactors. LÄS MER

4. 3. Optimization of Equipment for Tomographic Measurements of Void Distributions using Fast Neutrons

   Författare :Peter Andersson; Staffan Jacobsson Svärd; Henrik Sjöstrand; Ane Håkansson; Michael Österlund; Stephan Pomp; Rudi Van Nieuwenhove; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

   Sammanfattning : This licentiate thesis describes a novel nondestructive measuring technique for determiningspatial distributions of two-phase water flows. In Boiling Water Reactors, which compose themajority of the world's commercial nuclear reactors, this so called void distribution is of importance for safe operation. LÄS MER

5. 4. Gamma Spectroscopy and Gamma Emission Tomography for Fuel Performance Characterization of Irradiated Nuclear Fuel Assemblies

   Författare :Scott Holcombe; Staffan Jacobsson Svärd; Hans-Urs Zwicky; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear fuel performance; Nuclear fuel assemblies; Gamma emission tomography; Gamma spectroscopy;

   Sammanfattning : Gamma spectroscopy and gamma emission tomography are two non-destructive measurement techniques for assessing the performance of nuclear fuel which have been investigated in this thesis for existing and novel applications through theoretical studies and experimental demonstrations. For assessment of individual fuel rods using gamma spectroscopy, fuel assemblies are dismantled so that the fuel rods may be measured separately, which is time-consuming and may cause damage to the fuel. LÄS MER

7. 5. Nondestructive Fission Gas Measurements by Means of Gamma Spectroscopy and Gamma Tomography

   Författare :Scott Holcombe; Staffan Jacobsson Svärd; Guido Ledergerber; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik med inriktning mot tillämpad kärnfysik; Physics with specialization in Applied Nuclear Physics;

   Sammanfattning : There is a continuous need in the nuclear industry to characterize irradiated nuclear fuel rods and assemblies, both for fuel performance and for safeguards purposes, and consequently there are various destructive and nondestructive measurement techniques available to meet this need. Gamma spectroscopy is one such nondestructive technique, which has been extensively used for a variety of fuel characterization applications. LÄS MER