A heat exchanger for an air conditioner for which a zeotropic refrigerant mixture is used is obtained, and the heat exchanger, when used as an evaporator, enables reduction of the amount of required refrigerant without deteriorating the heat transfer performance. The heat exchanger includes: a plurality of fins stacked together at predetermined intervals therebetween; first heat transfer pipes which extend through the plurality of fins, in which a heat medium flows, and which have a plurality of grooves in the inner surface of the pipes; and second heat transfer pipes extending through the plurality of fins, having one end connected to one end of the first heat transfer pipes to form one heat medium flow path, being smaller in pipe diameter than the first heat transfer pipes, and having an inner surface shape providing a pressure loss per unit length smaller than that of the first heat transfer pipes.

A thermal management system and method includes a body having an inlet and an outlet configured to direct a first fluid into and out of the body. The body incudes a channel that is fluidly separate from the inlet and the outlet. A second fluid is directed through the channel. A conduit assembly is fluidly coupled with the inlet and the outlet. The conduit assembly includes plural fluidly separate conduits. Each of the plural conduits extend between a corresponding first end and a corresponding second end along a corresponding tortuous path. The plural conduits are intertwined with each other between the first ends and the second ends. The plural conduits are positioned such that the second fluid flowing through the channel passes over the plural conduits and exchanges thermal energy with the first fluid that moves within each of the plural conduits.

A flow reactor is structured to increase the overall heat transfer coefficient, which represents the efficiency of heat exchange with respect to a reactive fluid to be treated. This flow reactor is provided with three flow passages, which are a first flow passage, a second flow passage, and a third flow passage which spirally circulate within a space formed between an inner tube and an outer tube. The flow passages are compartmented by an inner heat transfer body and an outer heat transfer bodies. The heat transfer bodies spirally circulate, have a screw-like cross-sectional shape in an axial cross-sectional view, and are assembled in a screw-like configuration. By changing the shapes of a male-thread portion and a female-thread portion, the flow passage area of the first flow passage is changed, the second flow passage and the third flow passage are spirally formed, and heat exchange and reaction take place through the heat transfer bodies.

A heat exchanger with which a fluid to be treated or a generated gas can be prevented from stagnating in a heat transfer part, which can be disassembled for good washability, and which can be coated or lined. The heat exchanger is provided with tow flow passages, i.e. a first flow passage and a second flow passage, within a space formed between an inner tube and an outer tube which are concentric to each other. A spiral heat transfer body is disposed between the inner tube and the outer tube, and the spiral heat transfer body has a cross-sectional shape that is substantially triangular in the axial-direction cross section. The space is partitioned into the first flow passage and the second flow passage by the spiral heat transfer body, and heat is exchanged via the spiral heat transfer body between a first fluid flowing within the first flow passage and a fluid flowing within the second flow passage.

A counter-flow heat exchanger comprising a heat exchanger core including an inner wall and an outer wall radially outward and spaced apart from the inner wall. A first flow path is defined within the inner wall and a second flow path is defined between the inner wall and the outer wall. The heat exchanger core includes a primary flow inlet, a primary flow outlet and a middle portion therebetween. The inner and outer walls are concentric at the primary flow inlet of the heat exchanger core. The inner wall defines a first set of channels extending axially from the primary flow inlet to the middle portion of the heat exchanger core diverging away from a radial center of the heat exchanger core. The inner wall and the outer wall define a second set of channels extending axially from the primary flow inlet to the middle portion of the heat exchanger core converging toward the radial center of the heat exchanger core.

A counter-flow heat exchanger comprising a heat exchanger core including an inner wall and an outer wall radially outward and spaced apart from the inner wall. A first flow path is defined within the inner wall and a second flow path is defined between the inner wall and the outer wall. The heat exchanger core includes a primary flow inlet, a primary flow outlet and a middle portion therebetween. The inner and outer walls are concentric at the primary flow inlet of the heat exchanger core. The inner wall defines a first set of channels extending axially from the primary flow inlet to the middle portion of the heat exchanger core diverging away from a radial center of the heat exchanger core. The inner wall and the outer wall define a second set of channels extending axially from the primary flow inlet to the middle portion of the heat exchanger core converging toward the radial center of the heat exchanger core.

A tube for a steam cracking furnace comprising: at least one downstream tubular segment of circular section having a main diameter; at least one twisted tubular segment having a length less than a quarter of the length of the tube, and comprising: a central part with an elliptical or lobed section, having a helical pitch between one times and ten times the main diameter, and an aspect ratio of the elliptical or lobed section between 0.5 and 0.8; an upstream transition part establishing a geometric transition between the central part and a tubular segment of circular section; a downstream transition part establishing a geometric transition between the central part and the downstream tubular segment, with a fluid being intended to flow from the upstream transition part to the downstream transition part.

A tube for a steam cracking furnace comprising: at least one downstream tubular segment of circular section having a main diameter; at least one twisted tubular segment having a length less than a quarter of the length of the tube, and comprising: a central part with an elliptical or lobed section, having a helical pitch between one times and ten times the main diameter, and an aspect ratio of the elliptical or lobed section between 0.5 and 0.8; an upstream transition part establishing a geometric transition between the central part and a tubular segment of circular section; a downstream transition part establishing a geometric transition between the central part and the downstream tubular segment, with a fluid being intended to flow from the upstream transition part to the downstream transition part.

Heat exchanger fins and heat exchangers are disclosed. The heat exchanger fins disclosed herein comprise louvers and winglet-type vortex generators arranged to improve heat transfer efficiency.

Heat exchanger fins and heat exchangers are disclosed. The heat exchanger fins disclosed herein comprise louvers and winglet-type vortex generators arranged to improve heat transfer efficiency.