A heat exchanger may include a collector and a connecting pipe. The collector may include at least one insertion opening. The connecting pipe may be inserted in the at least one insertion opening. The connecting pipe may include at least one bulge projecting radially to the outside. The at least one bulge may form a stop of the connecting pipe in an insertion direction in the at least one insertion opening. The at least one bulge may indicate a predefined angle-of-rotation position of the connecting pipe in the at least one insertion opening.

The present disclosure provides a heat exchanger flat tube and a heat exchanger with the heat exchanger flat tube, the heat exchanger flat tube includes two plates opposite to each other, a fluid passage is formed between the two plates, a turbulence structure is provided in the fluid passage and has a gradually expanding portion and a gradually narrowing portion, both an extension direction of the gradually expanding portion and an extension direction of the gradually narrowing portion are consistent with a flow direction of a fluid, and the gradually narrowing portion is located downstream of the gradually expanding portion along the flow direction of the fluid.

A heat exchanger includes a tube having a length and an outside boundary. The tube is configured to convey fluid therethrough to facilitate heat transfer, and the outside boundary of the tube having a bottom wall portion, a top wall portion opposing the bottom wall portion, and two side wall portions between the bottom wall portion and the top wall portion, in which a segment of the length of the tube has a plurality of dimples selectively placed outside of the bottom wall portion.

A heat exchanger includes a plurality of first members, and a plurality of second members located between adjacent first members of the plurality of first members. The plurality of first members each include a plurality of openings and a first flow path connected to the plurality of openings. The plurality of second members each include a second flow path connected to the openings of the adjacent first members. The plurality of openings and the first flow path of the first member, and the second flow path of the second member define a flow path for a first fluid. A region between the adjacent first members defines a flow path for a second fluid. The heat exchanger further includes a third member extending toward the region on the first member.

The present invention relates to a heat exchanger of an exhaust heat recovery apparatus having a simple structure which is configured such that exhaust gas is evenly distributed, thereby preventing a boiling phenomenon wherein coolant water is boiling, and improving efficiency of heat exchange and durability of the apparatus.

A heat exchanger includes a plurality of tubes arranged in a juxtaposed configuration, and at least one first manifold member on the outside of the tubes. Each tube is wound to define a planar spiral, having a plurality of co-planar turns, and has an end portion, which extends starting from the inside of the corresponding planar spiral towards the outside thereof. The end portion is superimposed on the co-planar turns, in a position corresponding to a major face of the planar spiral, for connection to the manifold member. tube has a transverse depression defined in the co-planar turns at the major face of the planar spiral, and the transverse depression at least partially receives a a corresponding part of the end portion.

A heat exchange device may include a first pipe including a first inlet, a first outlet, and a first sidewall extending therebetween; a second pipe including a second inlet, a second outlet, and a second sidewall extending therebetween; and a plurality of dimples extending between the first sidewall and the second sidewall. The second sidewall may surround and extend about the first sidewall, the first sidewall may define a first fluid passage configured to permit flow of a first fluid, and the second sidewall and the first sidewall may define a second fluid passage configured to permit flow of a second fluid.

A flat tube for a header-plateless heat exchanger has an inner plate and an outer plate that are each press-molded from a metal plate and are curved/folded into a groove shape comprising a groove bottom section and two side wall sections. Both plates are such that the outer plate is fitted to the outside of the inner plate in a manner such that the groove bottom sections oppose each other, and an expanded opening in the thickness direction is formed at both ends of the plates.

A heat exchanger includes tube expansion portions provided respectively on a plurality of heat transfer tubes such that outer peripheral surfaces of the heat transfer tubes are respectively pressed against inner peripheral surfaces of a plurality of first holes provided in a side wall portion of a case, and a plurality of first concave surface portions provided in an outer surface of the tube expansion portion so that first gaps, into which brazing material of a first brazed portion advances, are formed between the outer surface of the tube expansion portion and the inner peripheral surface of the first hole. At least one of the plurality of first concave surface portions is positioned in an outside peripheral surface portion of the outer peripheral surface of the heat transfer tube. According to this configuration, the strength with which the heat transfer tubes are attached to the case can be increased while simplifying a manufacturing operation and reducing the manufacturing cost.

A heat exchanger for a water heater having a burner includes an outer tube extending longitudinally along a centerline from a first end adjacent the burner to a second end. Indentations are formed along the length of the outer tube and extend towards the centerline. An inner member extends through the outer tube and between the indentations such that flue gases from the burner flow in a passage between the inner member and the outer tube from the first end to the second end of the outer tube.