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.

In a method for closing open ends of tubes, an open tube end is closed using spin-tubing methods known in the art. Following the tube end closing, a concavity is formed in the tube end in a tube end forming machine. The tube end is brazed with the tube end facing upright, so that the braze alloy pools in the concavity, strengthening the tube end.

In a method for closing open ends of tubes, an open tube end is closed using spin-tubing methods known in the art. Following the tube end closing, a concavity is formed in the tube end in a tube end forming machine. The tube end is brazed with the tube end facing upright, so that the braze alloy pools in the concavity, strengthening the tube end.

A method for determining a stiffness of a tube bundle heat exchanger. The heat exchanger has a core tube and a plurality of coil tubes coiled around the core tube to form a tube bundle having a plurality of coil layers at a respective layer coiling angle. The method determines a geometric strength parameter for a coil layer, the strength parameter being an area ratio of a coil-tube cross-sectional area to a cell cross-sectional area resulting from the axial spacing of the coil tubes and an outer diameter of the coil tubes. The area ratio is corrected by a correction factor taking the orientation of the coil tubes of the coil layer in relation to the force of gravity acting on the coil tubes into consideration. The stiffness of the respective coil layer is determined from the corrected area ratio and a modulus of elasticity of the coil-tube material.

A method for determining a stiffness of a tube bundle heat exchanger. The heat exchanger has a core tube and a plurality of coil tubes coiled around the core tube to form a tube bundle having a plurality of coil layers at a respective layer coiling angle. The method determines a geometric strength parameter for a coil layer, the strength parameter being an area ratio of a coil-tube cross-sectional area to a cell cross-sectional area resulting from the axial spacing of the coil tubes and an outer diameter of the coil tubes. The area ratio is corrected by a correction factor taking the orientation of the coil tubes of the coil layer in relation to the force of gravity acting on the coil tubes into consideration. The stiffness of the respective coil layer is determined from the corrected area ratio and a modulus of elasticity of the coil-tube material.

A tube for use in a heat exchanger includes an upper portion, a base portion spaced from the upper portion, and a partitioning wall depending from the upper portion. The partitioning wall is bent away and spaced from the base portion in a first section of the tube to form a single flow channel within the tube along the first section. The partitioning wall contacts the base portion in a second section of the tube to form a partition separating a first flow channel from a second flow channel along the second section. The first section of the tube is configured for reception into an opening of a header tank of the heat exchanger.

A method for manufacturing boiler tubes includes the steps of removing end caps from a plurality of tubes, the plurality of tubes including at least a first tube and a second tube, cleaning an outer surface of the first tube and the second tube, forming a weld preparation on an upstream end of the first tube, forming a weld preparation on a downstream end of the second tube, welding the upstream end of the first tube to the downstream end of the second tube to form a butt weld, to produce a long tube, and with an automated device, measuring a parameter of at least the first tube and the second tube. The steps of removing the end caps, cleaning the outer surface of the tubes, forming the weld preparations, welding the first tube to the second tube, and measuring the parameter are performed autonomously.

A method for manufacturing boiler tubes includes the steps of removing end caps from a plurality of tubes, the plurality of tubes including at least a first tube and a second tube, cleaning an outer surface of the first tube and the second tube, forming a weld preparation on an upstream end of the first tube, forming a weld preparation on a downstream end of the second tube, welding the upstream end of the first tube to the downstream end of the second tube to form a butt weld, to produce a long tube, and with an automated device, measuring a parameter of at least the first tube and the second tube. The steps of removing the end caps, cleaning the outer surface of the tubes, forming the weld preparations, welding the first tube to the second tube, and measuring the parameter are performed autonomously.

An evaporator suitable for a thermal dissipation module. The thermal dissipation module includes a tube or pipe and fluid. The evaporator includes a housing, a first heat dissipation structure and a second heat dissipation structure disposed in a sealed chamber of the housing. The chamber is configured to communicate with the pipe, and the fluid is configured to flow in the pipe and the chamber. The first heat dissipation structure and a second heat dissipation structure provide a plurality of fluid flow passages through which the fluid flows and evaporates. A manufacturing method of the evaporator is also disclosed.

A heat exchanger having at least one inner conduit comprising of a second tubular member coaxially disposed within a first tubular member, wherein the second tubular member outer surface is in contact with the first tubular member inner surface. Each of the first and second tubular members is composed of a material with an approximately 0.015 inch maximum wall thickness.