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Real-time radiography was successfully applied to the Titan-IV Solid Rocket Motor Upgrade (SRMU) static firing test QM-2 conducted February 22, 1993 at Phillips Laboratory, Edwards AFB, CA. The real-time video data obtained in this test gave the first incontrovertible evidence that the molten slag pool is low (less than 5 to 6 inches in depth referenced to the bottom of the aft dome cavity) before T + 55 seconds, builds fairly linearly from this point in time reaching a quasi-equilibrium depth of 16 to 17 inches at about T + 97 seconds, which is well below the top of the vectored nozzle, and maintains that level until T + 125 near the end motor burn. From T + 125 seconds to motor burn-out at T + 140 seconds the slag pool builds to a maximum depth of about 20 to 21 inches, still well below the top of the nozzle. The molten slag pool was observed to interact with motions of the vectored nozzle, and exhibit slosh and wave mode oscillations. A few slag ejection events were also observed.

This document establishes the software design, nomenclature, and conventions for industrial Computed Tomography (CT) used in the Nondestructive Evaluation Section at Lawrence Livermore National Laboratory. It is mainly a users guide to the technical use of the CT computer codes, but also presents a proposed standard for describing CT experiments and reconstructions. Each part of this document specifies different aspects of the CT software organization. A set of tables at the end describes the CT parameters of interest in our project. 4 refs., 6 figs., 1 tab.

X-ray computed axial tomography (CAT or CT) is an advanced imaging technique which provides three-dimensional nondestructive inspection and characterization of materials, components and assemblies. The Lawrence Livermore National Laboratory (LLNL) and the Mason Hanger-Silas Mason Co., Pantex Plant are cooperating to examine the use of CT Technology to inspect high-explosive (HE) pressings. The goals of this joint project are to study the HE pressing process using computed tomography scanners, to provide a foundation for the further development of industrial CT scanners, and to work with the private sector on the design and implementation of an automated CT inspection scanner to be used in the manufacturing process of high explosives at the Pantex Plant. The early detection of defective HE pressings will reduce the cost and improve the safety of the high-explosives production cycle. At present, all pressings are bulk density tested. In addition, samples are randomly selected from each pressing lot for destructive core sampling to obtain an estimate of internal density gradients. CT is a viable technology for a high-explosives inspection system. CT measures density variations, detects foreign inclusions and voids with a probability of detection as good as or better than present inspection techniques. In addition, CT canmore » be fully automated to allow for a 100% sample inspection. LLNL has the advantage of several different in-house built CT scanners to bring to bear on the inspection of high explosives. A preliminary study was performed to evaluate the LLNL CT scanners and prove the characterization principles associated with CT on small PBX9502 high-explosive samples. This paper summarizes the results obtained, and introduces the capabilities of LLNL's Nondestructive Evaluation Section CT scanners. 36 refs., 50 figs.« less

Radioscopy and transmission x-ray computerized tomography (TCT) were used to analyze as simulated waste canister. This study was performed to demonstrate the qualitative and quantitative possibilities obtained by TCT scanners over radioscopy and how TCT can be applied toward the solution of materials and waste management problems. This report provides a brief summary of the scanner (CATALYST) used, a description of the waste canister and its contents, and an analysis of three radiographic views and the two scans obtained at two different slice planes on the canister. The usefulness of TCT is demonstrated by how well it reveals the interior details and spatial positions of items within the simulated waste canister. This paper ends with a summary of this study and what further development is required for this technology to be better used in materials and waste management. 9 refs., 13 figs.

In x-ray and ion-beam computerized tomography, there are a number of reconstruction effects, manifested as artifacts, that can be attributed to the geometry of the experimental setup and of the object being scanned. In this work, we will examine four geometric effects that are common to first-and third-generation (parallel beam, 180 degree) computerized tomography (CT) scanners and suggest solutions for each problem. The geometric effects focused on in this paper are: X-pattern'' artifacts (believed to be caused by several errors), edge-generated ringing artifacts (due to improper choice of the reconstruction filter and cutoff frequency), circular-ring artifacts (caused by employing uncalibrated detectors), and tuning-fork artifacts (generated by an incorrectly specified center-of-rotation). Examples of four effects are presented. The X-pattern and edge-generated ringing artifacts are presented with actual experimental data introducing the artifact. given the source of the artifact, we present simulated data designed to replicate the artifact. Finally, we suggest ways to reduce or completely remove these artifacts. The circular-ring and tuning-fork artifacts are introduced with actual experimental data as well, while digital signal processing solutions are employed to remove the artifacts from the data. 15 refs., 12 figs.