Heat spreader

About: Heat spreader is a research topic. Over the lifetime, 13686 publications have been published within this topic receiving 196268 citations.

Heat sink for cooling a heat producing element and application

Abstract: A heat sink mounted on a heat producing element for cooling the heat producing element attached on the printed board of the electronic apparatus, having a heat sink body made of a good heat conductive material and a fan assembly installed inside the heat sink body. The heat sink body is efficiently air-cooled by a cooling air generated by the rotation of the fan assembly. The cooling air forcibly cools a base and a fixing wall of the base adjacent to the heat producing element and plate-like radiating fins or a pin-like radiating fins are protruded on the heat sink body to radiate the heat effectively. The position of the fan assembly is at the center of the heat sink body or is at the offset position from the center of the heat sink body. The heat sink of the present invention can be installed in a portable electronic apparatus such as a portable computer.

Numerical modeling of non-adiabatic heat-recirculating combustors

Abstract: A two-dimensional numerical model of spiral counterflow heat recirculating combustors was developed including the effects of temperature-dependent gas and solid properties, viscous flow, surface-to-surface radiative heat transfer, heat conduction within the solid structure, one-step chemical reaction and heat loss from the combustor to its surroundings. A simplified model of heat loss in the 3rd dimension was implemented and found to provide satisfactory representation of such losses at greatly reduced computational cost compared to fully three-dimensional models. The model predicts broad reaction zones with structure decidedly different from conventional premixed flames. Extinction limits were determined over a wide range of Reynolds numbers (2 500, modeling of turbulent flow and transport was required to obtain such agreement. Heat conduction along the heat exchanger wall has a major impact extinction limits; the wall thermal conductivity providing the broadest limits is actually less than that of air. Radiative heat transfer between walls was found to have an effect similar to that of heat conduction along the wall. In addition to weak-burning extinction limits, strong-burning limits in which the reaction zone moves out of the combustor center toward the inlet were also predicted by the numerical model, in agreement with experiments. It is concluded that several physical processes including radiative transfer, turbulence and wall heat conduction strongly affect the performance of heat-recirculating combustors, but the relative importance of such effects is strongly dependent on Re.

Power semiconductor module

Abstract: A power semiconductor module with its thermal resistance and overall size reduced Insulating substrates with electrode metal layers disposed thereon are joined to both the surfaces of a power semiconductor chip by using, for example, soldering Metal layers are disposed also on the reverse surfaces of the insulating substrates and the metal layers are joined to the heat spreaders by using brazing Heat radiating fins are provided on the heat radiating surface of at least one of the heat spreaders The heat radiating side of each of the heat spreaders is covered by a casing to form a refrigerant chamber through which refrigerant flows to remove heat transmitted from the semiconductor chip to the heat spreader