Acrylic Plastic Spherical Pressure Hull for 2439 m (8000 ft) Design Depth: Phase I

1987 ◽  
Vol 109 (1) ◽  
pp. 40-47 ◽  
Author(s):  
J. D. Stachiw ◽  
A. Clark ◽  
C. B. Brenn
Keyword(s):  
Phase I ◽  
Scale Model ◽  
Test Plan ◽  
Short Term ◽  
Acrylic Plastic ◽  
Hull Design ◽  
Manned Submersible ◽  
Design Depth ◽  
Different Diameters ◽  
Spherical Pressure

A program has been initiated to provide the oceanographic community with a manned submersible with panoramic visibility for 2439 m (8000 ft) design depth. The first phase of the program is to validate the design of the acrylic plastic pressure hull utilizing model scale spheres with different diameters and thickness to inside diameter (t/Di) ratios. This papers summarizes 1) the criteria used in the design of the acrylic plastic hull for 2439 m (8000 ft) depth, 2) the experimental test plan for validation of the hull design, and 3) the fabrication, and short-term pressurization to destruction of the first scale model with an aluminum hatch. The 457-mm (18-in.) o.d. acrylic sphere with t/Di ratio of 0.2 successfully withstood 1-hr long pressurizations from 0 to 6.9, 13.8, 20.7, 27.6, 34.4 and 41.3 MPa (1000, 2000, 3000, 4000, 5000, and 6000 psi) followed by 1-hr long relaxation periods after each pressurization prior to imploding at 110.2 MPa (16,000 psi) under 4.5 MPa/min (650 psi/min) pressurization. The selected t/Di ratio 0.2 appears to exceed the design depth requirement for 2439 m (8000 ft).

NEMO Type Acrylic Plastic Spherical Hull for Manned Operation to 3000 ft Depth

1976 ◽  
Vol 98 (2) ◽  
pp. 537-549 ◽  
Author(s):  
J. D. Stachiw
Keyword(s):  
Fatigue Life ◽  
Stress Wave ◽  
Cyclic Fatigue ◽  
Short Term ◽  
Destructive Testing ◽  
Pressure Cycling ◽  
Acrylic Plastic ◽  
Scale Models ◽  
Spherical Pressure

NEMO Mod 2000 acrylic plastic pressure hull assembly represents the latest addition to the NEMO hull series represented by NEMO Mod 600 and 1000 hull assemblies. The 66 in. OD × 58 in. ID spherical acrylic hull with aluminum hatches has successfully withstood 24 hr long external hydrostatic pressurizations to 450, 900, 1350, and 1800 psi. Pressure cycling and short term destructive testing of 15 in. OD × 13 in. ID scale models has shown that the crackfree fatigue life is in excess of 1000 pressure cycles to 1500 psi and the short term implosion pressure is in the range of 4750–5000 psi. Stress wave emissions have been found to be a good indicator of incipient failure. NEMO Mod 2000 spherical pressure hulls with panoramic visibility are considered to be acceptable for manned submersibles with 3000 ft operational depth capability. The cyclic fatigue life of such hulls is conservatively predicted to be at least 12 × 106 ft hr.

Window Seat Weight Reduction Exploration With Nontraditional Seat Geometry

2019 ◽  
Vol 53 (1) ◽  
pp. 107-116 ◽  
Author(s):  
Thomas Trudel ◽  
Karl Stanley
Keyword(s):  
Pressure Vessels ◽  
Scale Model ◽  
Short Term ◽  
Element Analysis ◽  
Design Studies ◽  
Exploratory Testing ◽  
Design Depth ◽  
Strength And Stiffness ◽  
American Society ◽  
Design Pressure

AbstractThis article provides an overview of the design and exploratory testing of a nontraditional submersible window seat design. Typically, window seat geometry is guided by the American Society of Mechanical Engineers-Pressure Vessels for Human Occupancy-1 (ASME-PVHO-1) engineering standard as well as other references by ASME, Stachiw, etc. As viewing area increases, window seat geometry is partly driven by the size of the acrylic window and not solely by the requirements for a hull penetration of equivalent size. The discrepancy in strength and stiffness between the submersible hull materials and acrylic window can result in a window seat that is overbuilt relative to the required hull integrity. This research focuses on nontraditional window seat geometries that decrease weight while performing comparably to designs that conform to the ASME-PVHO-1 standard. A novel window seat is proposed with reductions in window seat weight between 22% and 33%. Design methodology, assumptions, Fine Element Analysis (FEA) results, deviations from the standard, and empirical design studies are summarized in detail. Two scale model windows were tested to their design depth for 102 cycles and showed acceptable signs of wear. FEA constraints were validated using strain gauge and displacement measurements on the conical and low pressure faces of the windows. Short Term Critical Pressure (STCP) testing was conducted in a hydrostatic pressure chamber where the two model windows reached 79% and 86% of their design pressure.

Flanged Acrylic Plastic Hemispherical Shells for Undersea Application

1975 ◽  
Vol 97 (1) ◽  
pp. 1-9 ◽  
Author(s):  
J. D. Stachiw ◽  
J. R. Maison
Keyword(s):  
Finite Element ◽  
Hydrostatic Pressure ◽  
Stress Distribution ◽  
Boundary Conditions ◽  
Critical Pressure ◽  
Convex Surface ◽  
Elastic Analysis ◽  
Short Term ◽  
Acrylic Plastic ◽  
Hemispherical Shells

The effects of an equatorial flange and a nonuniform wall thickness upon the critical pressure and stress distribution in acrylic plastic hemispheres have been investigated by experimental and analytical methods. Forty acrylic hemispheres were fabricated and tested to destruction under short term hydrostatic pressure applied on the convex surface. Dome apex displacements were obtained from each specimen and strains were obtained from a selected few. A finite element elastic analysis was performed on one window configuration for two different boundary conditions and the experimentally derived stresses were used to determine which boundary conditions was the best for analytical analysis.

Three-Dimensional Numerical Simulation of the Flow around Two Side-by-Side Cylinders of Different Diameters

2014 ◽  
Vol 721 ◽  
pp. 199-202
Author(s):  
Zhen Xiao Bi ◽  
Zhi Han Zhu
Keyword(s):  
Numerical Simulation ◽  
Flow Direction ◽  
Three Dimensional ◽  
Cross Flow ◽  
Simulation Method ◽  
Scale Model ◽  
Hydrodynamic Characteristics ◽  
Eddy Simulation ◽  
Drag And Lift ◽  
Different Diameters

This paper presents the calculation of hydrodynamic characteristics of two side-by-side cylinders of different diameters in three dimensional incompressible uniform cross flow by using Large-eddy simulation method based on dynamical Smagorinsky-Lilly sub-grid scale model. Solution of the three dimensional N-S equations were obtained by the finite volume method. The numerical simulation focused on investigating the characteristic of the pressure distribution (drag and lift force), vorticity field and turbulence Re=. Results shows that, the asymmetry of the time –averaged velocity distribution in the flow direction behind the two cylinders is very obvious; the frequency of eddy shedding of the small cylinder is about twice of the large one. The turbulence of cylinders is more obvious.

Polycarbonate Plastic Inserts for Spherical Acrylic Plastic Shells Under Hydrostatic Loading

1981 ◽  
Vol 103 (1) ◽  
pp. 90-98 ◽  
Author(s):  
J. D. Stachiw ◽  
R. B. Dolan ◽  
D. L. Clayton
Keyword(s):  
Fatigue Life ◽  
Structural Integrity ◽  
Structural Parameters ◽  
Cyclic Fatigue ◽  
Pressure Vessels ◽  
Plastic Shell ◽  
Acrylic Plastic ◽  
Hydrostatic Loading ◽  
Spherical Pressure

An acrylic plastic spherical pressure hull incorporating polycarbonate inserts for mounting of penetrators has been built and pressure tested. The transparent hull will serve as one atmosphere cockpit in Johnson-Sea-Link #3 submersible for 2500 ft. service. Tests have been conducted with model scale polycarbonate inserts in acrylic plastic spherical pressure hulls and windows to evaluate the structural integrity and cyclic fatigue life of polycarbonate plastic inserts and acrylic shells in which they are mounted under repeated hydrostatic pressurizations. Test results indicate that the short term, long term and cyclic fatigue life of a polycarbonate insert, serving as a bulkhead for electric or hydraulic penetrators in spherical acrylic plastic pressure hulls or windows, exceeds that of the acrylic plastic shell in which it is mounted. Structural parameters of polycarbonate inserts are discussed and design criteria formulated for their utilization in manned submersibles and pressure vessels for human occupancy. Particular emphasis is placed on selection of material, seal configuration, and retainment design.

scholarly journals Phase I trial of tremelimumab in combination with short-term androgen deprivation in patients with PSA-recurrent prostate cancer

2011 ◽  
Vol 61 (7) ◽  
pp. 1137-1147 ◽  
Author(s):  
Douglas G. McNeel ◽  
Heath A. Smith ◽  
Jens C. Eickhoff ◽  
Joshua M. Lang ◽  
Mary Jane Staab ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Phase I ◽  
Phase I Trial ◽  
Androgen Deprivation ◽  
Recurrent Prostate Cancer ◽  
Short Term

A clinical pharmacokinetics study of carzelesin given by short-term intravenous infusion in a phase I study

1998 ◽  
Vol 41 (5) ◽  
pp. 377-384 ◽  
Author(s):  
O. van Tellingen ◽  
C. J. A. Punt ◽  
Y. Groot ◽  
R. E. C. Henrar ◽  
A. Awada ◽  
...  
Keyword(s):  
Phase I ◽  
Intravenous Infusion ◽  
Phase I Study ◽  
Short Term ◽  
Clinical Pharmacokinetics ◽  
Pharmacokinetics Study
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