Abstract: A hydrogen-fuelled aircraft 200 comprises a fuselage, wings and a plurality of cylindrical elongate hydrogen storage tanks mounted on the exterior of the fuselage and disposed vertically above a plane containing the wing-tips of the aircraft. An aerodynamic fairing forms a continuous air-washed surface of the aircraft together with a lower portion of the fuselage. The hydrogen storage tanks extend generally parallel to the fuselage and are contained between the fairing and the fuselage. The aircraft provides for storage of a large volume of compressed hydrogen without compromising the volume of usable space within the fuselage. The aircraft is able to carry out flight missions comparable in range and payload to those of an equivalent conventionally-fuelled aircraft.

Abstract: An organic composite gas storage tank 300 comprises a hollow central portion 306 which is substantially cylindrical and formed integrally with first and second end portions 302, 304, and which defines a longitudinal tank axis 301. The first end portion comprises a hollow truncated conical region which meets the hollow central portion at a first end thereof. The hollow central portion comprises first and second hollow truncated conical portions 306A, 306B, the external radius of a given hollow truncated conical portion decreasing in a direction towards a corresponding end portion. The tank comprises an organic composite fibre winding extending between first and second positions along the length of the tank which coincide with the first and second hollow truncated conical portions of the hollow central portion respectively, biassing these portions together and increasing the axial strength of the central portion.

Abstract: An organic composite gas storage tank 100 comprises a hollow central portion 106 which is substantially cylindrical and formed integrally with first and second end portions 102, 104, and which defines a longitudinal tank axis 101. The first end portion 102 comprises a hollow truncated conical region 102A which meets the hollow central portion at a first end thereof, and a cylindrical region 102B which meets an end of the hollow truncated conical portion remote from the hollow central portion. An organic fibre winding 107 extends at least between axial positions which coincide with the hollow truncated conical region of the first end portion and the hollow central portion respectively. A hollow metal end-fitting 120 has a hollow truncated conical portion 124 embedded within the wall of the hollow truncated conical region of the first end portion, providing a long leakage path around the metal end-fitting.

Abstract: An organic composite gas storage tank 100 comprises a hollow central portion 106 which is substantially cylindrical and formed integrally with first and second end portions 102, 104, and which defines a longitudinal tank axis 301. The first end portion comprises a hollow truncated conical region which meets the hollow central portion at a first end thereof, the outer and inner radii of the hollow truncated conical region decreasing in a direction along the longitudinal tank axis away from the hollow central portion. An organic fibre winding 107 extends at least between axial positions which coincide with the hollow truncated conical region of the first end portion and the hollow central portion respectively. The first end portion has a higher axial strength than that achievable for hemispherical end portion of a tank of the prior art.

Abstract: A hydrogen-fuelled aircraft 200 comprises a fuselage, wings and a plurality of cylindrical elongate hydrogen storage tanks mounted on the exterior of the fuselage and disposed vertically above a plane containing the wing-tips of the aircraft. An aerodynamic fairing forms a continuous air-washed surface of the aircraft together with a lower portion of the fuselage. The hydrogen storage tanks extend generally parallel to the fuselage and are contained between the fairing and the fuselage. The aircraft provides for storage of a large volume of compressed hydrogen without compromising the volume of usable space within the fuselage. The aircraft is able to carry out flight missions comparable in range and payload to those of an equivalent conventionally-fuelled aircraft.

Abstract: A hydrogen storage tank has a composite laminate wall, a hydrogen-porous layer in contact with the outer surface of the composite laminate wall and a hydrogen-non-porous layer in contact with the outer surface of the hydrogen-porous layer, the hydrogen-non-porous layer having an output port for venting hydrogen which passes through the composite laminate wall and the hydrogen-porous layer from the interior of the tank. The tank allows hydrogen which leaks through the composite laminate wall to be collected and re-used. The invention also allows for the rate of hydrogen leakage from the tank to be measured, providing a measure of the structural integrity of the tank.

Abstract: An organic composite gas storage tank 100 comprises a hollow central portion 106 which is substantially cylindrical and formed integrally with first and second end portions 102, 104, and which defines a longitudinal tank axis 301. The first end portion comprises a hollow truncated conical region which meets the hollow central portion at a first end thereof, the outer and inner radii of the hollow truncated conical region decreasing in a direction along the longitudinal tank axis away from the hollow central portion. An organic fibre winding 107 extends at least between axial positions which coincide with the hollow truncated conical region of the first end portion and the hollow central portion respectively. The first end portion has a higher axial strength than that achievable for hemispherical end portion of a tank of the prior art.

Abstract: A solid oxide fuel cell stack (10) comprises a plurality of modules (12). Each module (12) comprises an elongate hollow member (14). Each hollow member (14) has at least one passage (32) extending longitudinally through the hollow member (14) for the flow of reactant. Each hollow member (14) has two parallel flat surfaces (16,18). At least one of the modules (12A, 12B, 12C) includes a plurality of solid oxide fuel cells (20). The solid oxide fuel cells (20) are arranged on the flat surfaces (16,18) of the modules (12A, 12B, 12C). At least one end (34) of each module (12) is connected to an end (36) of an adjacent module (12) to allow reactant to flow sequentially through the modules (12). The arrangement of the modules (12) provides compliance in the solid oxide fuel cell stack (10) and thermal and mechanical stresses in the solid oxide fuel cell stack (10) are reduced.

Abstract: A solid oxide fuel cell stack (10) comprises a plurality of modules (12). Each module (12) comprises an elongate hollow member (14). Each hollow member (14) has at least one passage (32) extending longitudinally through the hollow member (14) for the flow of reactant. Each hollow member (14) has two parallel flat surfaces (16,18). At least one of the modules (12A, 12B, 12C) includes a plurality of solid oxide fuel cells (20). The solid oxide fuel cells (20) are arranged on the flat surfaces (16,18) of the modules (12A, 12B, 12C). At least one end (34) of each module (12) is connected to an end (36) of an adjacent module (12) to allow reactant to flow sequentially through the modules (12). The arrangement of the modules (12) provides compliance in the solid oxide fuel cell stack (10) and thermal and mechanical stresses in the solid oxide fuel cell stack (10) are reduced.