Submarine Pressure Hull Research Articles

Ultimate strength of submarine pressure hulls with failure governed by inelastic buckling

The analysis of submarine pressure hull assumes great importance among structural engineers due to the complexity involved in the collapse mechanism of stiffened shell structures. In most of the cases, the failure of stiffened shell structures occurs due to elastic buckling. But for some combinations of shell-stiffener geometry and material characteristics, the structure can fail by inelastic buckling, for which the methods of analysis are meagre. In this paper, the analysis of submarine pressure hull structure in which the failure gets governed by inelastic buckling is demonstrated. Three different approaches have been employed to investigate the ultimate strength of the ring stiffened submarine pressure hull structure with inelastic buckling modes of failure. The methods used are ‘Johnson–Ostenfeld inelastic correction’, ‘imperfection method’ and ‘finite element approach’. A typical submarine shell structure has been analysed for the inelastic buckling failure using these three approaches and the results are discussed.

A Robust Approach to Jobshop Scheduling Problems in the Marine Environment

In industry the scheduling of large made-to-order products, such as submarines or ships, is typically implemented using precise time intervals. As a result of this, schedules rarely if ever reflect reality, and this can make the task of managing large projects difficult and potentially costly. Not surprisingly, robustness is a desired property of a schedule, bringing with it a greater stability with less uncertainty. In addressing these problems, this paper first describes a practical job shop model that is then extended to allow the inclusion of imprecise durations. By implementing this methodology on an industrial case study, a submarine pressure hull, a means of gauging and providing greater robustness of scheduling is determined. This investigation into robustness also shows that improvements can be made by optimizing pessimistic duration times in contrast to the common practice of using optimistic times.

COLLAPSE OF CORRUGATED CIRCULAR CYLINDERS UNDER UNIFORM EXTERNAL PRESSURE

The paper describes a finite element investigation into the buckling, under uniform external pressure, of four submarine pressure hulls. Two of these hulls were traditional ring-stiffened types, but two of these hulls were in the form of corrugated circular cylinders. The latter design was based on an invention by the present author. The investigation found that the new design was structurally efficient and in the case of the smaller vessel, it was found to be structurally more efficient than the conventional design.Another investigation, based on axisymmetric plastic buckling, was conducted on the two corrugated vessels, to determine if they were prone to collapse through the bellows' mode of failure. This investigation was carried out because former critics of this work stated that the corrugated circular cylinders would fail by the bellows' mode of failure. Neither of the two corrugated pressure hulls was found to fail through the bellows' mode of failure, thereby completely vindicating the present author. The author, however, concludes that the bellows' mode of failure can occur if the cone angles were too large.Two of the finite element theories were based on the author's work, but the giant computer package ANSYS was also used to study non-symmetric bifurcation buckling. This work was carried out to vindicate the author's in-house computer programs, which were simpler to use than ANSYS.

A method for the evaluation of the fatigue operational life of submarine pressure hulls

In this paper, a method is developed to calculate the fatigue lifetime of submarine pressure hulls, applying linear elastic fracture mechanics, based on the Paris equation. It is known that this structure is submitted to high stresses caused by variable hydrostatic pressure and residual stresses due to the welding process. The association of those variables may cause, after a certain period of time, material fatigue and fracture. Through the application of Paris' law, and based on an initial crack size, the crack size after a given number of load cycles, defined by the number of submarine dives, is obtained, furnishing information for possible pressure hull maintenance action, regarding crack repairs.

Statistical Power Flow Analysis of an Imperfect Ribbed Cylinder

Prediction of the noise transmitted from machinery and flow sources on a submarine to the sonar arrays poses a complex problem. Vibrations in the pressure hull provide the main transmission mechanism. The pressure hull is characterised by a very large number of modes over the frequency range of interest (at least 100,000) and by high modal overlap, both of which place its analysis beyond the scope of finite element or boundary element methods. A method for calculating the transmission is presented, which is broadly based on Statistical Energy Analysis, but extended in two important ways: (1) a novel subsystem breakdown which exploits the particular geometry of a submarine pressure hull; (2) explicit modelling of energy density variation within a subsystem due to damping. The method takes account of fluid–structure interaction, the underlying pass/stop band characteristics resulting from the near-periodicity of the pressure hull construction, the effect of vibration isolators such as bulkheads, and the cumulative effect of irregularities (e.g., attachments and penetrations).

Study of the nonlinear responses of a submersible pressure hull

A submarine pressure hull normally experiences hydrostatic pressure at different operating depths and, during wartime, it bears shock loading produced by underwater explosions. In this study we examine the transient dynamic responses of a typical submarine hull subjected to hydrostatic pressure and shock loading, in which geometrically large deformation effects involving elastoplastic material behavior are considered. The finite element procedure based on Hibbitt and Karlsson's methodology is used to analyze the nonlinear response of the entire pressure hull. From the numerical results of a nonlinear static analysis under operating depth hydrostatic pressure, we attempt to provide the maximum operating depth at which the behavior varies from elastic to plastic. In transient dynamic analysis under shock environment, this study not only presents the elastoplastic response of the structure but also the critical region of the model. Finally, the implications of these results for future submarine design and maintenance are discussed.

Enhancement of submarine pressure hull steel ultrasonic inspection using imaging and artificial intelligence : Hay, D.R.; Brassard, M.; Matthews, J.R.; Garneau, S.; Morchat, R. Nondestructive Evaluation of Aging Maritime Applications, Oakland, California (United States), 8 Jun. 1995. pp. 79–90. Edited by R.B. Mignogna. SPIE. Vol. 2459 (1995) ISBN 0-8194-1812-9

Enhancement of submarine pressure hull steel ultrasonic inspection using imaging and artificial intelligence : Hay, D.R.; Brassard, M.; Matthews, J.R.; Garneau, S.; Morchat, R. Nondestructive Evaluation of Aging Maritime Applications, Oakland, California (United States), 8 Jun. 1995. pp. 79–90. Edited by R.B. Mignogna. SPIE. Vol. 2459 (1995) ISBN 0-8194-1812-9

An investigation of the use of strain gages to measure welding-induced residual stresses

The measurement of weld-induced residual stress is important in structures that are subjected to cyclic loading during their service life. Depending on their magnitude, stresses can influence the rate of crack growth under cyclic loading and hence affect the life of the structure. Because the level of residual stress may change during service, measurement of these changes is necessary for accurate life prediction of the structures. The measurement of welding-induced residual stress using strain gages poses significant problems, the most important being the potential damage to the gages by high temperatures generated in the welding process. This laboratory study was undertaken to assess the suitability and signal stability of commercially available resistive strain gages for the measurement of postweld residual stresses in a submarine hull structure. Adhesively bonded and weldable-type strain gages were attached to the surface of a 35 mm thick steel plate, which was then subjected to thermal cycles similar to those encountered during welding construction of a submarine pressure hull. This paper describes the strain gage application procedure, changes in the strain gage output at end of each experimental stage and the history of changes in the residual stress.

Comparing the error of the improved Bridge Gauge Transverse Method and Jig Method for circularity measurement

This paper presents three procedures for measuring and calculating the circularity of a submarine pressure hull. The Bridge Gauge Transverse Method is studied, detailed and improved. Improvements in the gauge itself are proposed and a new out-of-roundness mathematical calculation routine is developed. A Qualification Procedure to determine the calculating method effective accuracy is presented. The quality, utility and use of the proposed improved process during the submarine pressure hull fabrication steps is discussed, in comparison with the Jig Method.

Minimum weight design of submersible pressure hull under hydrostatic pressure

In this study, we proposed a minimum weight design of a submarine pressure hull under hydrostatic pressure with constraints on factors such as general instability, buckling of shell between frames, plate yielding, and frame yielding. A typical submarine pressure hull is also adopted for a prototype model. This design problem is not only formulated as a discrete nonlinear, nondifferentiable, multimodal constrained minimization problem, but also solved by using the backtrack programming method. Results in this study indicate that the solution for the optimal model's weight reduces an average 6.65% more than the prototype model. The process in this study is favorable for the submersible pressure hull design process.

Automated ultrasonic system for submarine pressure hull inspection : Chan, R.W.Y.; Hay, D.R.; Matthews, J.R.; MacDonald, H.A. Signal Processing and Pattern Recognition in Nondestructive Evaluation of Materials, Proceedings of the NATO Advanced Research Workshop, Lac Beauport, Quebec, Canada, 19–22 Aug. 1987. Edited by C.M. Chen, pp. 175–188. Springer-Verlag (1988)

Automated ultrasonic system for submarine pressure hull inspection : Chan, R.W.Y.; Hay, D.R.; Matthews, J.R.; MacDonald, H.A. Signal Processing and Pattern Recognition in Nondestructive Evaluation of Materials, Proceedings of the NATO Advanced Research Workshop, Lac Beauport, Quebec, Canada, 19–22 Aug. 1987. Edited by C.M. Chen, pp. 175–188. Springer-Verlag (1988)

Automated ultrasonic system for submarine pressure hull inspection : Signal Processing and Pattern Recognition in Nondestructive Evaluation of Materials, Proceedings of the NATO Advanced Research Workshop, Lac Beauport, Quebec, Canada, 19–22 Aug. 1987. Edited by C.M. Chen, pp. 175–188. Springer-Verlag (1988)

Automated ultrasonic system for submarine pressure hull inspection : Signal Processing and Pattern Recognition in Nondestructive Evaluation of Materials, Proceedings of the NATO Advanced Research Workshop, Lac Beauport, Quebec, Canada, 19–22 Aug. 1987. Edited by C.M. Chen, pp. 175–188. Springer-Verlag (1988)

Effect of cyclic waveforms with superimposed high frequency flutter on the corrosion fatigue behaviour of a submarine hull steel

Abstract : In the past, several investigators have reported changes in the stress corrosion fatigue behavior when small amplitude high frequency flutter loading was superimposed on a static load or the hold portion of cycle waveform. In a more recent study it was reported that in the presence of seawater the fatigue life (basic trapezoidal cycles) decreased when the superimposed flutter frequency increased from 1 Hz to 20 Hz. Above 20 Hz, and up to 30 Hz at least, no further frequency dependence was observed. The significance of the past findings are of considerable practical importance especially dealing with a new steel (Australian designation BIS 812 EMA) for a submarine pressure hull application.

A Novel Submarine Pressure Hull Design

The paper presents an alternative design for a submarine pressure hull, which has no ring-stiffeners, but where shell instability and general instability are resisted by making the pressure hull of a swedged-shaped form. Calculations on two different-sized pressure hulls appear to indicate that the swedged-shaped hulls are more structurally efficient than their ring-stiffened equivalents.

A New Shipbuilding Measurement Tool—Photogrammetry for Measuring Circularity of Submarine Hulls

Photogrammetry is the art, science, and technology used in the interpretation of coordinate data about physical objects by the measurement and analysis of photographic images. This paper is concerned with the use of photogrammetry to measure the as-built circularity (out-of-roundness) of the Trident Class submarine pressure hull cylinders Various other mechanical methods have been used in the past for measuring hull circularities, but the unique features and capabilities of photogrammetry have proved themselves well in meeting demanding shipyard needs. The large, awkward shape of submarine pressure hull cylinders, m combination with the flexibility and ease of the use of the photogrammetric technique, makes photogrammetry a productive tool in support of submarine construction.

Random polar sampling technique for the reliability analysis of submarine pressure hull

Reliability analysis is essential to reduce the structural system failures to an acceptance level. In this paper, a quasi-Monte Carlo Simulation method called ‘Random Polar Sampling Technique' (RPST) has been described for the reliability analysis of ring stiffened shell structure, in which the combinations of variates are obtained using a polar sampling of Latin hypercube sampled values. An efficient computer program coded in C++ has been developed for use with the RPST. Reliability analysis of internally ring stiffened submarine pressure hull has been described as an illustration and the results are compared with those given by First Order Second Moment method (FOSM), Advanced First Order Second Moment method (AFOSM) and Monte-Carlo Simulation methods. Keywords: Random Polar Sampling Technique, Reliability, Ring stiffened shells, Submarine pressure hull, Latin Hypercube Samples.  doi: 10.3329/jname.v1i1.2036 Journal of Naval Architecture and Marine Engineering 1(2004) 26-34

Structural Research on Submarine Pressure Hulls at the David Taylor Model Basin

For many years, there has been a need for improved pressure hulls for underwater vehicles because of the ever-present demands for better performance of military submarines. Growing interest in exploration and exploitation of the ocean depths has recently given impetus to the development of reliable high-strength, low-density hulls required to achieve deep operating depths while maintaining small vehicle size. The David Taylor Model Basin has been playing a key role in developing pressure-hull structures for various underwater applications. This paper summarizes some principal theoretical and experimental results of recent Model Basin studies. Specifically, it describes advances in the strength analysis of shell structures and investigations of the structural problems associated with the introduction of new hull materials. Preliminary results of studies aimed at developing a pressure hull and flotation system for the 20,000-ft search vehicle of the deep submergence systems project are also presented.

COMPARATIVE BEHAVIOR OF SUBMARINE PRESSURE HULL STRUCTURES OF DIFFERENT SCALES UNDER UNIFORM EXTERNAL PRESSURE

Naval Engineers JournalVolume 75, Issue 2 p. 397-404 COMPARATIVE BEHAVIOR OF SUBMARINE PRESSURE HULL STRUCTURES OF DIFFERENT SCALES UNDER UNIFORM EXTERNAL PRESSURE F. W. DUNHAM, F. W. DUNHAM F. W. Dunham received his undergraduate education at Bucknell University in Civil Engineering, with specialization in structures. He has been associated with the structural design of naval ships since graduation, starting at the Philadelphia Naval Shipyard in 1939, and transferring to the Bureau of Ships in Washington, D. C in 1945. Since 1951 he has been primarily concerned with the structural design of submarines, and was responsible for directing the Bureau's research effort for improving structural design. In 1959 he transferred to Portsmouth Naval Shipyard to his present position of assistant Chief Design Engineer for Naval Architecture.Search for more papers by this authorCAPTAIN S. R. HELLER JR. USN, CAPTAIN S. R. HELLER JR. USN Captain Heller, an Engineering Duty Officer of the United States Navy, received his undergraduate education at the University of Michigan in Naval Architecture and Marine Engineering and in Mathematics. Following typical shipyard duty during World War II, he received postgraduate instruction at the Massachusetts Institute of Technology leading to the degrees of Naval Engineer and Doctor of Science in Naval Architecture. Since then he has had design responsibilities in the Bureau of Ships, a maintenance assignment with the Fleet, directed structural research at the David Taylor Model Basin, and is now engaged in submarine design at Portsmouth Naval Shipyard.Search for more papers by this author F. W. DUNHAM, F. W. DUNHAM F. W. Dunham received his undergraduate education at Bucknell University in Civil Engineering, with specialization in structures. He has been associated with the structural design of naval ships since graduation, starting at the Philadelphia Naval Shipyard in 1939, and transferring to the Bureau of Ships in Washington, D. C in 1945. Since 1951 he has been primarily concerned with the structural design of submarines, and was responsible for directing the Bureau's research effort for improving structural design. In 1959 he transferred to Portsmouth Naval Shipyard to his present position of assistant Chief Design Engineer for Naval Architecture.Search for more papers by this authorCAPTAIN S. R. HELLER JR. USN, CAPTAIN S. R. HELLER JR. USN Captain Heller, an Engineering Duty Officer of the United States Navy, received his undergraduate education at the University of Michigan in Naval Architecture and Marine Engineering and in Mathematics. Following typical shipyard duty during World War II, he received postgraduate instruction at the Massachusetts Institute of Technology leading to the degrees of Naval Engineer and Doctor of Science in Naval Architecture. Since then he has had design responsibilities in the Bureau of Ships, a maintenance assignment with the Fleet, directed structural research at the David Taylor Model Basin, and is now engaged in submarine design at Portsmouth Naval Shipyard.Search for more papers by this author First published: May 1963 https://doi.org/10.1111/j.1559-3584.1963.tb04879.xCitations: 1 AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume75, Issue2May 1963Pages 397-404 RelatedInformation