Damage and leakage barrier in all-composite pressure vessels and storage tanks
A linerless tank structure has a body that defines an enclosed interior volume. The body has a cylindrical section having an axis of symmetry and a dome section coupled with the cylindrical section. The construction of the pressure vessel includes multiple fiber plies. At least one of the fiber plies is a helical ply having fibers traversing the dome helically about the axis of symmetry. At least a second of the fiber plies is a braided or woven ply.
1. An all-composite pressure vessel or storage tank defining an enclosed interior volume and comprising:
a plurality of structural plies;
one or more barrier plies comprising:
reinforcement fibers that impart a predictable, burst-strain capacity to the barrier plies; and
a polymeric resin that provides a resistance to microcracking and incipient leakage under pressurization and leading up to strains that exceed the burst-strain capacity of the barrier plies;
wherein the barrier plies exhibit a burst strain that is less than a burst strain exhibited by the plurality of structural plies.
2. The all-composite pressure vessel or storage tank recited in claim 1 wherein the fibers in the barrier plies are filament-wound or fiber-placed.
3. The all-composite pressure vessel or storage tank recited in claim 1 wherein the fibers in the barrier plies are braided or woven.
4. The all-composite pressure vessel or storage tank recited in claim 1 wherein the fiber in each of the barrier plies are divided into two sets of fibers intersecting each other at an angle that results in a substantially uniform tensioning of both sets of fibers in reaction to internal pressurization of the pressure vessel or storage tank.
5. The all-composite pressure vessel or storage tank recited in claim 1 wherein the polymeric resin is highly ductile.
6. The all-composite pressure vessel or storage tank recited in claim 1 wherein the first mode of failure under pressurization is rupture of the barrier plies, leading to leakage of the pressurized contents.
7. The all-composite pressure vessel or storage tank recited in claim 1 wherein barrier and nonbarrier plies exhibit substantially equivalent in-plane thermal-expansion coefficients.
8. The all-composite pressure vessel or storage tank recited in claim 1 wherein barrier and nonbarrier plies exhibit substantially equivalent electrical and galvanic properties.
9. The all-composite pressure vessel or storage tank recited in claim 1 wherein the barrier plies carry a predetermined fraction of a total load that develops within the all-composite pressure vessel or storage tank in response to internal pressurization.
10. The all-composite pressure vessel or storage tank recited in claim 1 wherein the barrier ply is an innermost barrier layer for the all-composite pressure vessel or storage tank.
11. The all-composite pressure vessel or storage tank recited in claim 1 wherein each nonbarrier ply is disposed between two barrier plies.
12. The all-composite pressure vessel or storage tank recited in claim 1 wherein each barrier ply is disposed between two nonbarrier plies.
13. The all-composite pressure vessel or storage tank recited in claim 1 wherein nonbarrier plies are interleaved with barrier plies.
14. The all-composite pressure vessel or storage tank recited in claim 1 wherein the barrier plies traverse all sections of the all-composite pressure vessel or storage tank.
15. The all-composite pressure vessel or storage tank recited in claim 1 wherein the barrier plies traverse only portions of the all-composite pressure vessel or storage tank.
16. A storage tank comprising:
one or more barrier layers comprising
a plurality of fibers;
a ductile resin; and
a plurality of non-barrier layers,
wherein the first mode of failure under pressurization is rupture of the barrier layer.
17. A storage tank comprising:
one or more barrier layers comprising a plurality of braided fibers and a ductile resin; and
a plurality of structural layers comprising fibers and resin, wherein at least one of the structural layers is disposed over one of the barrier layers,
wherein the first mode of failure under pressurization is rupture of the barrier layer.