Schnelle dynamische Radiographie an einem thermischen Hochfluss-Neutronenstrahl. Fast dynamic radiography at a high-flux thermal neutron beam

Ruprecht-Karls-Universit¨at Heidelberg, 2003. 52 p. (на английском языке) Die Diplomarbeit wurde von ausgef¨uhrt am Physikalischen Institut HeidelbergFast dynamic radiography at a high-flux ther-mal neutron beam We report on first dynamic radiographies with millisecond time resolution measured at the new neutron radiography and tomography facility Neutrograph at the Institut Laue-Langevin (ILL) in Grenoble (France). We visualized the fuel jet from a diesel direct injection nozzle and recorded dynamic radiographies of a running combustion engine and an externally driven car engine. Further measurements included two-phase flow of pentane in a thin heated steel pipe, water penetration in building materials, and water transport into a lecithin lamellar phase. We put Neutrograph into operation at the ILL beamline H9. It provides the high thermal flux of 2.9×109 n cm−2 s−1 and the sufficiently low divergence of 6 mrad that permit fast dynamic radiography with sub-millimeter resolution. The properties of Neutrograph are discussed, especially those of the detector.Introduction Basics of Neutron Radiography Measuring Principle Tomography Comparison with other Methods Beam and Detector The Beam The Detector The Scintillator The Camera The Detector Housing The Casemate Radiation Protection Safety Error Analysis Systematic Errors Scintillator Degradation Intensity Fluctuations Statistical Errors . Contrast Spatial Resolution Time Resolution Image Intensifiers Data Treatment Measurements Combustion Engines Introduction Injection Nozzle Running Engine Car Engine Further Measurements Two-Phase Flow Building Materials Myelin OutlookA Derivations Bibliography Acknowledgements Declaration Instructions for the CD