Persistent Link:
http://hdl.handle.net/10150/184552
Title:
Axially accelerated saboted rods subjected to lateral forces.
Author:
Rabern, Donald Allen.
Issue Date:
1988
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The methodology and analysis used to characterize the performance of a sabot/rod as it is subjected to lateral and axial loading during launch is presented. The methodology described incorporates the experimental and numerical portions of the evaluation. Three separate sabot/rod designs are evaluated for their performance in the launch tube and are compared with one another. The experimental portion of the research involved full-scale testing of two separate sabot/rod designs in a 120-mm launch tube that was slightly bent. When launched through the bent tube, the sabot/rod system was forced to negotiate lateral displacements at axial velocities of approximately 5400 fps. This combination of axial velocity and lateral displacement produced significant lateral loading on the sabot/rod system. A 2.3-MeV x-ray unit was used to determine the lateral displacement that occurred as the sabot/rod was forced through the bent tube. After the sabot/rod exited the launch tube, the sabot separation and rod straightness were recorded by four 150-keV x-ray units. The in-bore radiography experiments used x-ray shielding techniques to reduce x-ray scatter, and layered indexed film and intensifier screens to record the sabot/rod image. The processed film was computer scanned with a microdensitometer and was remapped on the computer to enhance the x-ray image. Results indicated rod lateral displacement accuracy to 0.007 in. Test results were used to benchmark the numerical analyses used to characterize the in-bore performance of each sabot/rod system studied. The numerical portion of the research involved three-dimensional modeling of the sabot/rod systems in three launch-tube environments: a perfectly straight launch tube, an existing accuracy tube, and the slightly bent tube used in the experimental program. Because of the good agreement between the experimental and numerical models, stress, strain, and displacement time histories were obtained from the numerical work and used to evaluate each of the three sabot/rod systems in three launch environments. A dynamic analysis was performed for each of nine separate models. Sliding surfaces, nonlinear constitutive relations, and multiple materials were used for each analysis. Results from both the experimental and numerical analyses are presented.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Rockets (Aeronautics) -- Launching.; Acceleration (Mechanics)
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Civil Engineering and Engineering Mechanics; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Richard, Ralph M.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleAxially accelerated saboted rods subjected to lateral forces.en_US
dc.creatorRabern, Donald Allen.en_US
dc.contributor.authorRabern, Donald Allen.en_US
dc.date.issued1988en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe methodology and analysis used to characterize the performance of a sabot/rod as it is subjected to lateral and axial loading during launch is presented. The methodology described incorporates the experimental and numerical portions of the evaluation. Three separate sabot/rod designs are evaluated for their performance in the launch tube and are compared with one another. The experimental portion of the research involved full-scale testing of two separate sabot/rod designs in a 120-mm launch tube that was slightly bent. When launched through the bent tube, the sabot/rod system was forced to negotiate lateral displacements at axial velocities of approximately 5400 fps. This combination of axial velocity and lateral displacement produced significant lateral loading on the sabot/rod system. A 2.3-MeV x-ray unit was used to determine the lateral displacement that occurred as the sabot/rod was forced through the bent tube. After the sabot/rod exited the launch tube, the sabot separation and rod straightness were recorded by four 150-keV x-ray units. The in-bore radiography experiments used x-ray shielding techniques to reduce x-ray scatter, and layered indexed film and intensifier screens to record the sabot/rod image. The processed film was computer scanned with a microdensitometer and was remapped on the computer to enhance the x-ray image. Results indicated rod lateral displacement accuracy to 0.007 in. Test results were used to benchmark the numerical analyses used to characterize the in-bore performance of each sabot/rod system studied. The numerical portion of the research involved three-dimensional modeling of the sabot/rod systems in three launch-tube environments: a perfectly straight launch tube, an existing accuracy tube, and the slightly bent tube used in the experimental program. Because of the good agreement between the experimental and numerical models, stress, strain, and displacement time histories were obtained from the numerical work and used to evaluate each of the three sabot/rod systems in three launch environments. A dynamic analysis was performed for each of nine separate models. Sliding surfaces, nonlinear constitutive relations, and multiple materials were used for each analysis. Results from both the experimental and numerical analyses are presented.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectRockets (Aeronautics) -- Launching.en_US
dc.subjectAcceleration (Mechanics)en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineCivil Engineering and Engineering Mechanicsen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorRichard, Ralph M.en_US
dc.identifier.proquest8905804en_US
dc.identifier.oclc701553078en_US
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