A technique to additively print onto a dissimilar material, especially ceramics and glasses (e.g., semiconductors, graphite, diamond, other metals) is disclosed herein. The technique enables manufacture of heat removal devices and other deposited structures, especially on heat sensitive substrates. It also enables novel composites through additive manufacturing. The process enables rapid bonding, orders-of-magnitude faster than conventional techniques.

Provided is a positive temperature coefficient (PTC) unit for a vehicle heater. The PTC unit according to an exemplary embodiment of the present invention includes: a heat generation part which includes PTC elements; and a heat radiation part which is provided on at least one surface of the heat generation part and includes a heat radiation base material and a heat radiation film provided on at least a portion of an outer surface of the heat radiation base material to improve heat radiation performance. According to the present invention, improved heat radiation performance may be exhibited, and concurrently, heat radiation performance due to excellent durability may be exhibited for a long period of time without a structural change for increasing a specific surface area of a heat radiation part while reducing an air ventilation property, so as to improve heat radiation performance. In addition, since an air ventilation property of the heat radiation part is increased, it is possible to prevent increases in noise and power consumption due to excessive use of peripheral devices such as a fan. Furthermore, since it is possible to prevent overheating of a PTC module and overload of a PTC module control circuit, which are caused by a reduction in the air ventilation property of the heat radiation part, a high-priced and high performance control circuit may not be required, thereby implementing a PTC heater for a vehicle with reduced production costs.

Provided is a positive temperature coefficient (PTC) unit for a vehicle heater. The PTC unit according to an exemplary embodiment of the present invention includes: a heat generation part which includes PTC elements; and a heat radiation part which is provided on at least one surface of the heat generation part and includes a heat radiation base material and a heat radiation film provided on at least a portion of an outer surface of the heat radiation base material to improve heat radiation performance. According to the present invention, improved heat radiation performance may be exhibited, and concurrently, heat radiation performance due to excellent durability may be exhibited for a long period of time without a structural change for increasing a specific surface area of a heat radiation part while reducing an air ventilation property, so as to improve heat radiation performance. In addition, since an air ventilation property of the heat radiation part is increased, it is possible to prevent increases in noise and power consumption due to excessive use of peripheral devices such as a fan. Furthermore, since it is possible to prevent overheating of a PTC module and overload of a PTC module control circuit, which are caused by a reduction in the air ventilation property of the heat radiation part, a high-priced and high performance control circuit may not be required, thereby implementing a PTC heater for a vehicle with reduced production costs.

A method for fabricating a heat sink including providing a carbon metal composite having a plurality of metal-coated carbon fibers and a plurality of openings, the openings leading from a first side of the carbon metal composite to a second side of the carbon metal composite, disposing the carbon metal composite over a semiconductor element such that the first side of the carbon metal composite faces the semiconductor element, and bonding the carbon metal composite to the semiconductor element by means of an electroplating process, wherein a metal electrolyte is supplied to an interface between the carbon metal composite and the semiconductor element via the plurality of openings.

A method of recovering waste heat includes pressurizing a flow of working fluid and transferring heat from a hot gas stream to the flow of working fluid in at least two successively arranged heat transfer sections. At least some of the working fluid is converted to a superheated vapor by the transfer of heat, and passes through an expander to recover useful work. A portion of the flow of working fluid is directed along a branch after having passed through at least one of the heat transfer sections, and bypasses the expander and at least one of the heat transfer sections before being recombined with the working fluid that has passed through the expander. The total flow rate of working fluid can be adjusted to regulate the temperature of the hot gas stream downstream of the heat transfer sections, and the amount of fluid that bypasses along the branch can be adjusted to regulate the temperature of the superheated vapor.

High thermal conductivity materials and methods of their use for thermal management applications are provided. In some embodiments, a device comprises a heat generating unit (304) and a thermally conductive unit (306, 308, 310) in thermal communication with the heat generating unit (304) for conducting heat generated by the heat generating unit (304) away from the heat generating unit (304), the thermally conductive unit (306, 308, 310) comprising a thermally conductive compound, alloy or composite thereof. The thermally conductive compound may include Boron Arsenide, Boron Antimonide, Germanium Carbide and Beryllium Selenide.

High thermal conductivity materials and methods of their use for thermal management applications are provided. In some embodiments, a device comprises a heat generating unit (304) and a thermally conductive unit (306, 308, 310) in thermal communication with the heat generating unit (304) for conducting heat generated by the heat generating unit (304) away from the heat generating unit (304), the thermally conductive unit (306, 308, 310) comprising a thermally conductive compound, alloy or composite thereof. The thermally conductive compound may include Boron Arsenide, Boron Antimonide, Germanium Carbide and Beryllium Selenide.

A flexible thermal conduit runs from a first housing portion of an electronic device to a second housing portion of the electronic device, to convey heat generated by an electronic component located in the first housing portion to a heat dissipation structure located in the second housing portion, where the second housing portion is flexibly coupled to the first housing portion, for example, by a hinge or other type of joint. The flexible conduit may include a plurality of layers of thin, flat thermally conductive material, which may be arranged to flex independently of each other in the region where the first and second housing portions are coupled.

An elongated heat pipe or vapor chamber is described. In examples, the heat pipe may include a tubular body comprising a hollow glass tube or fiber. The heat pipe may further include a wick within the tubular body and a working fluid within the tubular body. The wick may be made of glass, polymer, metal, etc. The wick may be an elongated cylinder disposed within the tubular body and, some cases, may be bonded to an inner floor of the tubular body. In examples, the wick may have an outer diameter substantially equal to an inner diameter of the tubular body. In examples, the wick may have a substantially cross-shaped cross section or may have a helical shape.

A header for a heat exchanger orients the position of an inlet port at an angle offset from the position of the outlet port on the header body in order to simplify the plumbing of the header within a system. In one implementation of a header for a heat exchanger, the header forms a header cavity defined by an external wall and which is separated into an inlet chamber and an outlet chamber by a dividing wall. An inlet port is defined within the external wall and is in fluid communication with the inlet chamber. Similarly, an outlet port is defined within the external wall and is in fluid communication with the outlet chamber. The inlet port is oriented on the external wall at an offset angle with respect to a position of the outlet port.