A tubular structure including an outer tube an inner tube arranged within the outer tube and at least one chamber formed between the outer tube and the inner tube. The tubular structure additionally includes at least one self-healing material arranged in the chamber, wherein the self-healing material is configured to solidify and/or expand upon contact with a reacting material.

Heat exchangers, heat exchanger systems, and hypersonic vehicles are provided. For example, a heat exchanger is provided that comprises a first chamber for receipt of a flow of cool fluid and a second chamber for receipt of a flow of hot fluid. The heat exchanger further comprises a buffer fluid flowpath for circulation of a buffer fluid therethrough. The buffer fluid circulates within the buffer fluid flowpath disposed between the first chamber and the second chamber to transfer heat from the hot fluid to the cool fluid. In certain embodiments, a hypersonic vehicle comprises such a heat exchanger, and the cool fluid is cryogenic or near-cryogenic fuel of the hypersonic vehicle and the hot fluid is engine bleed air from a hypersonic propulsion engine of the vehicle.

An additively manufactured heat exchanger configured to transfer heat between a first fluid and a second fluid includes a first channel with a first wall configured to port flow of a first fluid and a second channel with a second wall configured to port flow of a second fluid. The heat exchanger also includes a barrier channel containing unprocessed build powder provided by the additive manufacturing process and is located between the first wall and the second wall. The barrier channel is configured to prevent mixing of the first fluid and the second fluid when one of the first wall and the second wall ruptures.

A heat exchange tube and a heat exchanger are provided. A tube wall of the heat exchange tube includes a first wall and a second wall, a first segment of the first wall includes one of a first groove or a first protrusion, a second segment of the first wall includes one of a second groove or a second protrusion, a first segment of the second wall includes the other one of the first groove or the first protrusion, the first protrusion is arranged in the first groove, the second segment of the second wall includes the other one of the second groove or the second protrusion, and the second protrusion is arranged in the second groove. At least part of each of the first segment and the second segment of the first wall is arranged between the first segment and the second segment of the second wall.

A vertical bundle air-cooled heat exchanger, a finned tube assembly for an air cooled condenser and method for forming the same, and a system for removing thermal energy generated by radioactive materials. In one aspect, an air cooled condenser sized for industrial and commercial application includes an inlet steam distribution header for conveying steam, a condensate outlet header for conveying condensate, an array of tube bundles each having a plurality of finned tube assemblies having a bare steel tube with an exposed outer surface and a set of aluminum fins brazed directly onto the tube by a brazing filler metal. The steel tubes may be spaced apart by the aluminum fins and have an inlet end fluidly coupled to the inlet steam distribution header and an outlet end fluidly coupled to the outlet header. A forced draft fan may be arranged to blow air through the tube bundles.

An additively manufactured heat exchanger configured to transfer heat between a first fluid and a second fluid includes a first channel with a first wall configured to port flow of a first fluid and a second channel with a second wall configured to port flow of a second fluid. The heat exchanger also includes a barrier channel containing unprocessed build powder provided by the additive manufacturing process and is located between the first wall and the second wall. The barrier channel is configured to prevent mixing of the first fluid and the second fluid when one of the first wall and the second wall ruptures.

A heat exchange structure includes a primary heat exchange body with a first fluid channel fluidly separated from a second fluid channel by a barrier channel, an inlet manifold in fluid communication with the first fluid channel, and a secondary heat exchange body. The secondary heat exchange body is in fluid communication with the barrier channel, is arranged within the inlet manifold, and fluidly couples the barrier channel to the external environment. Fluid systems and heat exchange methods are also described.

Conduits for cooling a hydrocarbon stream and processes for using same. The conduit can include a first inner wall defining a first bore, a second inner wall defining a second bore, and an outer wall disposed about the first and second inner walls. The conduit can also include an annular support wall connected to an inner surface of the outer wall. An end of the second inner wall and an end of the annular support wall can define a perimeter opening that can be in fluid communication with the second bore. An annular flexible ring can be bonded to the annular support wall and can flexibly contact the first inner wall. A substantially annular cavity can be disposed between the second inner and the outer walls and in fluid communication with the perimeter opening. A quench fluid introduction port can be configured to introduce a quench fluid into the cavity.

A vertical bundle air-cooled heat exchanger, a finned tube assembly for an air cooled condenser and method for forming the same, and a system for removing thermal energy generated by radioactive materials. In one aspect, an air cooled condenser sized for industrial and commercial application includes an inlet steam distribution header for conveying steam, a condensate outlet header for conveying condensate, an array of tube bundles each having a plurality of finned tube assemblies having a bare steel tube with an exposed outer surface and a set of aluminum fins brazed directly onto the tube by a brazing filler metal. The steel tubes may be spaced apart by the aluminum fins and have an inlet end fluidly coupled to the inlet steam distribution header and an outlet end fluidly coupled to the outlet header. A forced draft fan may be arranged to blow air through the tube bundles.

A heat exchanger and an antenna assembly having the same are described herein that enable a compact antenna design with good thermal management. In one example, a heat exchanger is provided that includes tube-shaped body. A main cooling volume is formed between the top and bottom surfaces proximate to the outside wall. The main cooling volume has an inlet formed through the top surface and an outlet formed through the bottom surface. A return volume is formed adjacent the inside diameter wall and is circumscribed by the main cooling volume. The return volume has an outlet formed through the top surface and an inlet formed through the bottom surface. One or more exterior fins are coupled to an exterior side of the outside wall. A plurality of fins extend into the main cooling volume. A plurality of inner fins extend into a passage from the inside diameter wall.