Abstract: Active cooling technologies such as thermoelectrics can be used to introduce thermal “gain” into a cooling system and, when employed in combination with forced flow cooling loops, can provide an attractive solution for cooling high heat flux density devices and/or components. In such configurations, it can be advantageous to discontinuously flow thermal transfer fluid into thermal contact with the hot or cold side of a thermoelectric module (TEM), allow it to dwell while heat is transferred from or to the TEM, and resume the flow. In configurations in which the TEM operation is itself discontinuous, various relationships between thermal transfer fluid flow and TEM operation can be advantageously employed to temporally integrate thermoelectric action.

Abstract: A system to extract heat from a high power density device and dissipate heat at a convenient distance. The system circulates liquid metal in a closed conduit using one or more electromagnetic pumps for carrying away the heat from high power density device and rejecting the heat at a heat sink located at a distance. The system may make use of a thermoelectric generator to power the electromagnetic pumps by utilizing the temperature difference between the inlet and outlet pipes of the heat sink. The system also provides networks of primary and secondary closed conduits having series and parallel arrangements of electromagnetic pumps for dissipating heat from multiple devices at a remotely located heat sink.

Abstract: Active cooling technologies such as thermoelectrics can be used to introduce thermal “gain” into a cooling system and, when employed in combination with forced flow liquid metal cooling loops, can provide an attractive solution for cooling high heat flux density devices and/or components. In such configurations, it can be advantageous to configure fluid flows to provide heat transfer between hot-side and cold-side flows. For example, it can be desirable to substantially equilibrate temperature of liquid metal flows entering hot-side and cold-side paths. In this way, thermal differential (?T) across individual thermoelectric elements can be reduced, thereby improving efficiency of the thermoelectric. Various suitable recuperator designs are described including designs that provide heat exchange with and without mixture of respective flows.

Abstract: Active cooling technologies such as thermoelectrics can be used to introduce thermal “gain” into a cooling system and, when employed in combination with forced flow liquid metal cooling loops, can provide an attractive solution for cooling high heat flux density devices and/or components. Total cooling power can be increased by employing multiple thermoelectric elements. Indeed, by employing modern semiconductor technologies, including e.g., thin-film technologies, thermoelectric elements may be cost-effectively employed and configured in large arrays.

Abstract: Apparatus to provide effective removal of heat from a high power density device. The apparatus has a heat spreader and a heat sink structure. The heat spreader is divided into one or more chambers. Electromagnetic pumps are placed inside each chamber in a configuration that facilitates easy circulation of liquid metal inside the chamber. The liquid metal preferably is an alloy of gallium and indium that has high electrical conductivity and high thermal conductivity. The liquid metal carries heat from a localized area (over the high power density device) and distributes it over the entire spreader. This results in a uniform distribution of heat on the base of the heat sink structure and hence effective removal of heat by the heat sink structure.

Abstract: A fluidic apparatus and method for cooling a non-uniformly heated heat source such as an integrated circuit. The apparatus preferentially cools a non-uniformly heated integrated circuit. A coolant is introduced into a high-power region of the integrated circuit through an inlet. The coolant absorbs heat from this region and cools it. Thereafter, the coolant is transferred to the low-power region of the integrated circuit. After the coolant absorbs heat from the low-power region, it is removed from an outlet, which is connected to the low-power region of the integrated circuit.

Abstract: A system to extract heat from a high power density device and dissipate heat at a convenient distance. The system circulates liquid metal in a closed conduit using one or more electromagnetic pumps for carrying away the heat from high power density device and rejecting the heat at a heat sink located at a distance. The system may make use of a thermoelectric generator to power the electromagnetic pumps by utilizing the temperature difference between the inlet and outlet pipes of the heat sink. The system also provides networks of primary and secondary closed conduits having series and parallel arrangements of electromagnetic pumps for dissipating heat from multiple devices at a remotely located heat sink.

Abstract: A thermoelectric device with an improved figure-of-merit achieved by lowering the thermal conductivity of the thermoelectric device without significantly reducing electrical conductivity. The reduction in value of thermal conductivity is achieved by reducing the phonon thermal conductivity ?p without significantly affecting the electron thermal conductivity ?e. The reduction in phonon thermal conductivity ?p is accomplished in two steps: First the phonon conduction is decoupled and separated from the electron conduction by the use of an ultra-thin film semiconductor thermoelement. And second, the phonon conduction is selectively attenuated by the use of phonon-blocking structures without affecting the electron conduction. Methods for fabrication of the thermoelectric devices are also provided.

Abstract: The present invention provides configurations of direct current magnetohydrodynamic (DC MHD) pumps for enhanced performance in pumping of conducting fluids. The pumping is achieved by a force developed by the interaction of magnetic flux and electric current. The force acting on the conducting fluid can be increased by increasing the magnetic flux density or the path length of charge carriers. The path length of charge carriers is increased by using a centrifugal configuration of the pump. The magnetic flux density is increased by using unique magnet configurations. A two-magnet configuration, a four-magnet configuration or a Halbach array configuration is used to enhance the magnetic flux density in the fluid cavity.

Abstract: The present invention provides an improved fluid pump that combines a liquid metal MHD pump with a plurality of fluid flow valves. The pump comprises a suction and pumping assembly, the suction and pumping assembly in turn comprising a first vertical chamber and a second vertical chamber connected using an intermediate horizontal chamber, a liquid metal partially filling the suction and pumping assembly, and an AC-powered reciprocating MHD pump. The AC-powered reciprocating MHD pump drives the liquid metal in an oscillatory manner, causing the suction and pumping of a working fluid. The pump further comprises at least one inlet conduit connected to the suction and pumping assembly for enabling the suction of a working fluid, at least one outlet conduit connected to the suction and pumping assembly for enabling the pumping of the working fluid, and a plurality of valves in the inlet and outlet conduits to regulate the flow of the working fluid.

Abstract: Apparatus to provide effective removal of heat from a high power density device. The apparatus has a heat spreader and a heat sink structure. The heat spreader is divided into one or more chambers. Electromagnetic pumps are placed inside each chamber in a configuration that facilitates easy circulation of liquid metal inside the chamber. The liquid metal preferably is an alloy of gallium and indium that has high electrical conductivity and high thermal conductivity. The liquid metal carries heat from a localized area (over the high power density device) and distributes it over the entire spreader. This results in a uniform distribution of heat on the base of the heat sink structure and hence effective removal of heat by the heat sink structure.

Abstract: A system to provide effective removal of heat from a high power density device. The system has a heat spreader and a heat sink structure. The heat spreader is divided into one or more chambers. Electromagnetic pumps are placed inside each chamber in a configuration that facilitates easy circulation of liquid metal inside the chamber. The liquid metal preferably is an alloy of gallium and indium that has high electrical conductivity and high thermal conductivity. The liquid metal carries heat from a localized area (over the high power density device) and distributes it over the entire spreader. This results in a uniform distribution of heat on the base of the heat sink structure and hence effective removal of heat by the heat sink structure.

Abstract: A system to extract heat from a high power density device and dissipate heat at a convenient distance. The system circulates liquid metal in a closed conduit using one or more electromagnetic pumps for carrying away the heat from high power density device and rejecting the heat at a heat sink located at a distance. The system may make use of a thermoelectric generator to power the electromagnetic pumps by utilizing the temperature difference between the inlet and outlet pipes of the heat sink. The system also provides networks of primary and secondary closed conduits having series and parallel arrangements of electromagnetic pumps for dissipating heat from multiple devices at a remotely located heat sink.