A heatsink comprising a heat exchange device having a plurality of heat exchange elements each having a surface boundary with respect to a heat transfer fluid, having successive elements or regions having varying size scales. According to one embodiment, an accumulation of dust or particles on a surface of the heatsink is reduced by a removal mechanism. The mechanism can be thermal pyrolysis, vibration, blowing, etc. In the case of vibration, adverse effects on the system to be cooled may be minimized by an active or passive vibration suppression system.

A heatsink comprising a heat exchange device having a plurality of heat exchange elements each having a surface boundary with respect to a heat transfer fluid, having successive elements or regions having varying size scales. According to one embodiment, an accumulation of dust or particles on a surface of the heatsink is reduced by a removal mechanism. The mechanism can be thermal pyrolysis, vibration, blowing, etc. In the case of vibration, adverse effects on the system to be cooled may be minimized by an active or passive vibration suppression system.

A heat exchanger includes a shell, a coiled tube, and a swirler. The shell has an inlet and an outlet and forms a cavity. A first of a liquid refrigerant and a vapor refrigerant enters the inlet of the shell. The coiled tube is positioned within the cavity and is connected to an inlet tube from outside the shell and an outlet tube to outside the shell. A second of the liquid refrigerant and the vapor refrigerant enters the inlet tube of the coiled tube. The swirler is arranged adjacent the inlet of the shell and is dimensioned to distribute the first of the liquid refrigerant and the vapor refrigerant across the coiled tube.

A heat exchanger includes a shell, a coiled tube, and a swirler. The shell has an inlet and an outlet and forms a cavity. A first of a liquid refrigerant and a vapor refrigerant enters the inlet of the shell. The coiled tube is positioned within the cavity and is connected to an inlet tube from outside the shell and an outlet tube to outside the shell. A second of the liquid refrigerant and the vapor refrigerant enters the inlet tube of the coiled tube. The swirler is arranged adjacent the inlet of the shell and is dimensioned to distribute the first of the liquid refrigerant and the vapor refrigerant across the coiled tube.

A heat exchanger core includes: a first passage; and a second passage extending along the first passage. At least one of the first passage or the second passage includes a plurality of narrowed portions in which an area of a passage cross section orthogonal to a passage extension direction is minimum, and a plurality of enlarged portions in which the area is maximum. The plurality of narrowed portions and the plurality of enlarged portions are alternately disposed in the passage extension direction.

A heat exchange structure includes: two flow channels stacked in a stacking direction (Y direction) and thermally coupled to each other; and a fin structure detachably installed in at least one flow channel of the two flow channels. The fin structure includes fins arranged in a longitudinal direction (Z direction) of the at least one flow channel in which the fin structure is installed, the fins configured to form openings alternately arranged along the at least one flow channel on one side and the other side of the at least one flow channel in the stacking direction.

A heat sink comprising a heat exchange device having a plurality of heat exchange elements each having a surface boundary with respect to a heat transfer fluid, having a fractal variation therebetween, wherein the heat transfer fluid is induced to flow with respect to the plurality of fractally varying heat exchange elements such that flow-induced vortices are generated at non-corresponding locations of the plurality of fractally varying heat exchange elements, resulting in a reduced resonance as compared to a corresponding heat exchange device having a plurality of heat exchange elements that produce flow-induced vortices at corresponding locations on the plurality of heat exchange elements.

A heat exchanger for recovering heat from wastewater leaving a building and transferring the heat to freshwater for use in the building; it has an inner pipe defining an inner space for receiving wastewater that is being evacuated from the building; an outer pipe, wherein the inner pipe is placed in the outer pipe, and the outer surface of the inner pipe and the inner surface of the outer pipe define an interstitial space for receiving freshwater; a turbulator sheet located in the interstitial space that causes or increases turbulence of the freshwater for improving heat transfer between the freshwater and the wastewater; and two couplings, one on either end of the outer pipe and the inner pipe.

A heat exchanger for recovering heat from wastewater leaving a building and transferring the heat to freshwater for use in the building; it has an inner pipe defining an inner space for receiving wastewater that is being evacuated from the building; an outer pipe, wherein the inner pipe is placed in the outer pipe, and the outer surface of the inner pipe and the inner surface of the outer pipe define an interstitial space for receiving freshwater; a turbulator sheet located in the interstitial space that causes or increases turbulence of the freshwater for improving heat transfer between the freshwater and the wastewater; and two couplings, one on either end of the outer pipe and the inner pipe.

An active vortex generator adapts to a flow rate of fluid through and/or a heat flux applied through a heat exchanger channel to improve the heat transfer rate of the heat exchanger. In some implementations, the movement of the active vortex generator may be induced by the fluid flow through the heat exchanger channel. In some implementations, the movement of the active vortex generator may be induced through an externally applied force on the active vortex generator. An actuated active vortex generator is particularly suited to heat exchangers with high heat flux dissipation requirements. Locating an actuated active vortex generator proximate to such high heat flux dissipation locations provides for improved heat transfer that can be activated when needed, such as upon operation of a high heat flux component.