An inner spiral grooved tube includes: a tube body; and grooves and fins aligned in an inner circumferential direction of the tube body, wherein the grooves and the fins are formed in a spiral along a longitudinal direction, an outer diameter is 3 mm or more and 10 mm or less, a number of the fins is 30 to 60, made of a metal, a cross sectional shape of each of the fins has a rectangular shape having an apex angle of 0±10°, a ratio h/f is 0.90 or more and 3.40 or less, h being a fin height and f being fin width, a ratio c/f is 0.50 or more and 3.80 or less, c being a fin spacing, and an average of the ratio h/f and the ratio c/f is 0.8 or more and 3.3 or less.

A fuselage heat exchanger having channels for dissipating waste heat generated by fuel cells that power unmanned aerial vehicles (UAVs) or drones. A heat exchanger built into the fuselage can dissipate such waste heat. Coolant flowing through channels embedded within an aircraft fuselage panel dissipates heat to airflow around the outer surface of the fuselage.

In a mixed composition coating material for brazing, when a total mass of a solid material, an organic solvent, and water is defined as 100 mass %, the solid material are contained in an amount of 30 mass % or greater and 80 mass % or less with respect to the whole coating material, the organic solvent and the water is contained in a total amount of 20 mass % or greater and 70 mass % or less with respect to the whole coating material, and the water is contained in an amount of 0.4 mass % or greater and 2.5 mass % or less with respect to the whole coating material.

The invention provides an energy storage apparatus comprising a crucible having a cavity and a channel, a phase change material stored in the cavity of the crucible and a heat exchanger having an inlet and an outlet, wherein at least a portion of the heat exchanger is disposed along the channel. Also provided are methods of reversibly storing and/or extracting energy, and an energy storage array comprising a plurality of energy storage apparatus as described above.

A cooling unit includes a unit main body including a bottom portion, a peripheral wall portion rising from the peripheral edge of the bottom portion, and a sealing body for sealing an opening of the unit main body. The unit main body is joined to the sealing body through a plasticized region, and a void is formed at a position close to the unit main body with respect to a center of the plasticized region.

Methods, systems, and device for thermal energy storage are provided. For example, some embodiments include a thermal energy storage device that may include: a first casing wall; a second casing wall; and/or multiple support structures located between the first casing wall and the second casing wall. The multiple support structures may provide continuous thermal paths and/or continuous mechanical paths between the first casing wall and the second casing wall. The thermal energy storage device may be fabricated utilizing an additive manufacturing technique, such as direct laser metal sintering. Some embodiments may be manufactured utilizing printed metals, such as an aluminum alloy. In some embodiments, a phase-change material is charged between the first casing wall and the second casing wall. The phase-change material may include paraffin.

A method of achieving high heat transfer during cooling includes providing an aluminum body having an inner surface enclosing a channel, where the inner surface comprises microscale roughness features and microcavities configured to enhance nucleation site density during flow boiling. A refrigerant is transported through the channel. During the transport, the refrigerant absorbs heat from a thermal load and undergoes flow boiling. The heat is transferred to the refrigerant at an average heat transfer coefficient of at least about 10 kW/(m.sup.2.Math.K) at a mass flux of about 300 kg/(m.sup.2.Math.s).

A basic structural body for constructing heat dissipation device and a heat dissipation device are disclosed. The heat dissipation device includes a first basic structural body having a wick structure formed on one side surface thereof; and the first basic structural body and the wick structure are structural bodies formed layer by layer. Two pieces of first basic structural bodies can be correspondingly closed together to construct a heat dissipation device internally defining an airtight chamber. In this manner, the heat dissipation device can be designed in a more flexible manner.

A sink composed of metal, preferably composed of a solid metal block, in particular composed of aluminium, and also to a method and a tool for the production of same. The heat sink has a plurality of fluid lines for conducting cooling fluid which are separated from one another by heat sink ribs arranged between them, which are arranged next to one another and which run in a parallel manner. It is characterized in that the fluid lines are formed by grooves which are milled into the metal.

Mg and Bi are contained in each of a first fillet in a first braze joining portion in which a tube and a fin join, a second fillet in a second braze joining portion in which the tube and a header plate join, and a third fillet in a third braze joining portion in which the header plate and a tank body join. A concentration of Mg of each of the first to third fillets is from 0.2% or more to 2.0% or less by mass. When the tube includes a brazing material layer, a concentration of Mg of the tube at its plate thickness center is from 0.1% or more to 1.0% or less by mass. When the fin includes a brazing material layer, a concentration of Mg of the fin at its plate thickness center is from 0.2% or more to 1.0% or less by mass.