An evaluation of the neutron radiography facility at the Nuclear Science Center for dynamic imaging of two-phase hydrogenous fluids

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to digital@library.tamu.edu, referencing the URI of the item.Includes bibliographical references.Though both film and video radiographic image techniques are available in neutron radiography, radiographic cameras are commonly used to capture the dynamic flow patterns in a rapid sequence of images. These images may be useful to verify two-phase flow models in small diameter flow channels. An initial series of real-time neutron radiography experiments were performed at the Texas A&M University System, Texas Engineering Experiment Station, Nuclear Science Center Reactor (NSCR) to determined the image resolution of two-phase water and air flow regimes through small diameter metal flow channels. After evaluating these initial images, research was conducted to determine cost effective enhancements that would increase the dimensional accuracy and contrast of these flow images. Modifications were completed to the beam collimator and the radiography camera video processing board was realigned to provide a stronger vidio signal with less noise. Several hydrogenous-media reference standards were designed and constructed to evaluate the effectiveness of the modifications. The beamport collimator was redesigned and the radiography calibration methodology was changed. The post-modification images demonstrate that a smaller, more focused neutron beam and a more sensitive video camera provide clearer images with excellent dimensional characteristics. Specific research to quantify both the resolution and sensitivity limits is proposed and a change in dynamic target imaging methodology is proposed