title: High resolution gamma ray tomography scanner for flow measurement and non-destructive testing applications.
abstract: We report on the development of a high resolution gamma ray tomography scanner that is operated with a Cs-137 isotopic source at 662 keV gamma photon energy and achieves a spatial image resolution of 0.2 line pairs/ mm at 10% modulation transfer function for noncollimated detectors. It is primarily intended for the scientific study of flow regimes and phase fraction distributions in fuel element assemblies, chemical reactors, pipelines, and hydrodynamic machines. Furthermore, it is applicable to nondestructive testing of larger radiologically dense objects. The radiation detector is based on advanced avalanche photodiode technology in conjunction with lutetium yttrium orthosilicate scintillation crystals. The detector arc comprises 320 single detector elements which are operated in pulse counting mode. For measurements at fixed vessels or plant components, we built a computed tomography scanner gantry that comprises rotational and translational stages, power supply via slip rings, and data communication to the measurement personal computer via wireless local area network.
authors.affiliation: Institute of Safety Research, Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 51 01 19, 01314 Dresden, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Hampel
authors.forename: A
authors.initials: A
authors.lastname: Bieberle
authors.forename: D
authors.initials: D
authors.lastname: Hoppe
authors.forename: J
authors.initials: J
authors.lastname: Kronenberg
authors.forename: E
authors.initials: E
authors.lastname: Schleicher
authors.forename: T
authors.initials: T
authors.lastname: Sühnel
authors.forename: F
authors.initials: F
authors.lastname: Zimmermann
authors.forename: C
authors.initials: C
authors.lastname: Zippe
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis / Q000295:instrumentation* / Q000379:methods; D005720:Gamma Rays; D007089:Image Enhancement / Q000295:instrumentation* / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation* / Q000379:methods; D016247:Information Storage and Retrieval / Q000379:methods*; D015203:Reproducibility of Results; D012212:Rheology / Q000295:instrumentation* / Q000379:methods; D012680:Sensitivity and Specificity; D041622:Tomography, Optical / Q000295:instrumentation* / Q000379:methods