Susumu Ogata

Bio: Susumu Ogata is an academic researcher from Fujitsu. The author has contributed to research in topics: Evaporator & Loop heat pipe. The author has an hindex of 7, co-authored 18 publications receiving 155 citations.

Loop heat pipe and electronic apparatus

Abstract: A loop heat pipe includes: an evaporator to convert liquid phase working fluid into vapor phase working fluid; a condenser to convert vapor phase working fluid into liquid phase working fluid; a first vapor line and a first liquid line to allow the evaporator to communicate with the condenser and form a circular main loop; and a second vapor line and a second liquid line to allow the evaporator to communicate with the condenser and form a circular auxiliary loop; wherein the evaporator includes a reservoir that temporarily stores the liquid phase working fluid, a first vapor collector that communicates with the first vapor line, a second vapor collector that communicates with the second vapor line, first wick disposed between the reservoir and the first vapor collector, and second wick disposed between the reservoir and the second vapor collector.

Cooling apparatus and electronic apparatus

Abstract: A cooling apparatus includes: an evaporator, including a porous body, a vapor channel and a liquid channel separated by the porous body, to evaporate a working fluid in liquid phase; a condenser to condense the working fluid in vapor phase; a liquid reservoir tank to reserve the working fluid in the liquid phase; a vapor line connecting an outlet of the vapor channel in the evaporator and an inlet of the condenser; a liquid line connecting an outlet of the condenser and a first inlet of the liquid reservoir tank; a liquid supply line connecting an outlet of the liquid reservoir tank and an inlet of the liquid channel in the evaporator; a liquid return line connecting an outlet of the liquid channel in the evaporator and a second inlet of the liquid reservoir tank; and a liquid transport unit interposed in the liquid supply line.

Cooling device using loop type heat pipe

Abstract: A cooling device which is provided with an evaporator with a built-in wick, a condenser, and a loop type heat pipe which connects the evaporator and condenser in a loop and is provided with a liquid pipe and vapor pipe, wherein the evaporator is divided into a liquid-pipe-side case and a vapor-pipe-side case and wherein a plurality of discharge ports of working fluids and a wick in which the working fluid from the discharge ports is completely permeated are arranged between the two cases. The wick is provided with projecting parts which have recessed parts corresponding to the discharge ports, while the outer circumferential surfaces of the projecting parts are provided with grooves. The working fluid which permeates the wick is changed to a vapor inside the vapor-pipe-side case, collects in the evaporation chamber, and is discharged to the liquid pipe, and thus, dry out of the wick is prevented.

Performance evaluation of ultra-thin polymer pulsating heat pipes

Abstract: An ultra-thin polymer pulsating heat pipe (PPHP) was developed by forming with UV curable polymer resin on polyethylene terephthalate films and hydrofluoroether was used as a working fluid. The casing materials were selected in consideration of compatibility between case materials and the working fluid and also the heat and pressure durability. A new apparatus was constructed to evaluate the thermal resistance of the PPHP without the heat dissipation caused by natural convection, and a simple model was developed to estimate the heat dissipation and identify their influence on the thermal performance measurement. Comparing experimental results in this apparatus with the results calculated by the model, we found that the uncertainty of the thermal resistance measurement caused by the heat dissipation could be reduced to the range of measurement error. The steady state operation of the PPHP in the horizontal orientation was confirmed by the temperature response to various heat loads and the observation of the working fluid pulsations. Performance evaluation of the PPHP using this apparatus showed that the thermal resistance of the PPHP decreased as heat load increased and reached a minimum value comparable with that of a copper plate of the same thickness.

Loop heat pipe, and electronic apparatus including loop heat pipe

Abstract: There is provided a loop heat pipe which includes an evaporator that internally includes at least one wick built, a condenser, a liquid pipe and a vapor pipe that connect the evaporator and the condenser to each other, and a heat dispersion cavity that is formed inside the evaporator, and disperses a vapor, wherein the wick includes, a first wick that is porous, a second wick that is porous, the second wick being inserted into the first wick from the liquid pipe side and including a pore size larger than the first wick, and a vapor channel that is defined between the first wick and the second wick. The vapor channel is connected at an end on the liquid pipe side to the heat dispersion cavity.

Gas cooled condensers for loop heat pipe like enclosure cooling

Abstract: A cooling device includes an enclosure, an external heat rejection device, a primary cooling system including a loop heat pipe like device. The LHPL device includes, an evaporator module, a condenser module, a vapor line, a liquid return line, and a working fluid having a liquid phase and a vapor phase. The evaporator module includes a component-evaporator heat spreader, an evaporator body, and an evaporator-component clamping mean. The evaporator body includes an evaporator outer shell, a working fluid inlet port, a compensation chamber, a working fluid exit port, and an evaporator wick having vapor escape channels. The condenser module includes a condenser coolant inlet, a condenser coolant exit, a condenser condensation channel, a condensation channel working fluid inlet, a condensation channel working fluid exit, and a condensation channel-coolant thermal interface further comprises a coolant passageway. The secondary cooling system including a secondary coolant, the secondary cooling system cooling a secondary heat rejecting component, wherein the secondary heat rejecting component is one of the plurality of other components.

Counter-flow heat exchanger for battery thermal management applications

Abstract: A heat exchanger for thermal management of battery units made-up of plurality of battery cells or battery cell containers housing one or more battery cells is disclosed. The heat exchanger has a main body portion defining at least one primary heat transfer surface for surface-to-surface contact with a corresponding surface of at least one of the battery cells or containers. A plurality of alternating first and second fluid flow passages are formed within the main body portion each defining a flow direction, the flow direction through the first fluid flow passages being generally opposite to the flow direction through the second fluid flow passages providing a counter- flow heat exchanger. In some embodiments the heat exchanger has a two pairs of inlet and outlet manifolds, the heat exchanger providing a single- pass, counter-flow arrangement. In other embodiments the first and second fluid flow passages are interconnected by turn portions forming a U-flow, counter-flow heat exchanger.