Phase change materials, heat exchangers, and related thermocells

Abstract

The PCM can have a phase transition temperature in the range of approximately 3°C to approximately 27°C. The PCM comprises 35% to 60% by weight of at least one inorganic salt, 1% to 9% by weight of at least one nucleating agent, 1% to 4% by weight of at least one thickener, and water, which typically constitutes 30% to 66%. The PCM can be used in a thermocell (1) which includes a tank (2) for housing the PCM. The thermocell (1) includes a HEX4 having a plurality of plates (5), each defining fluid channels (7) that extend across the plates (5). The plates (5) are arranged in a regular arrangement within the tank (2) such that the fluid channels (7) of each plate (5) are alternately offset with respect to the fluid channels of adjacent plates.

Claims

[Claim 1] A phase change material (PCM) having a phase change temperature of approximately 3°C to approximately 27°C, 35% to 60% by weight of inorganic salts; 1% to 9% by weight of a nucleating agent; A thickening agent in an amount of 1% to 4% by weight; and PCM containing 30% to 66% by weight of water. [Claim 2] The phase change temperature is approximately 3°C to approximately 6°C. 51% to 60% by weight of inorganic salts; 3% to 9% by weight of a nucleating agent; A thickening agent in an amount of 1% to 4% by weight; and The PCM according to claim 1, comprising 30% to 40% by weight of water. [Claim 3] The inorganic salt contains 38% to 43% by weight of dipotassium hydrogen phosphate and Contains 13% to 17% by weight of potassium fluoride. The PCM according to claim 2. [Claim 4] The nucleating agent is 1% to 3% by weight of dicalcium phosphate; 1% to 3% by weight of aluminum oxide; and The PCM according to claim 2 or 3, comprising 1% to 3% by weight of sodium chloride. [Claim 5] The PCM according to any one of claims 2 to 4, wherein the thickening agent is a superabsorbent polymer. [Claim 6] The PCM according to claim 5, wherein the superabsorbent polymer is sodium polyacrylate and / or carbomer. [Claim 7] The phase change temperature is approximately 4°C to approximately 5°C, and the PCM is Approximately 40.3% by weight of dipotassium hydrogen phosphate; Approximately 15.0% by weight of potassium fluoride; Approximately 2.3% by weight of dicalcium phosphate; Approximately 2.3% by weight of aluminum oxide; Approximately 2.3% by weight of sodium chloride; Approximately 2.7% by weight of sodium polyacrylate and / or carbomer; and The PCM according to claim 1, comprising approximately 35.2% by weight of water. [Claim 8] The aforementioned PCM has the following characteristics: At least approximately 190 kJ / kg of latent heat; At least approximately 0.9 W / m·K of solid-state thermal conductivity; Thermal conductivity in the liquid phase of at least approximately 0.5 W / m·K; Specific heat capacity in the solid phase of at least approximately 1.4 kJ / kg·K; Specific heat capacity in the liquid phase at least approximately 2.0 kJ / kg·K; At least approximately 1700 kg / m 3 Density in the solid phase; and / or At least approximately 1600 kg / m 3 The PCM according to claim 7, having at least one density in the liquid phase. [Claim 9] The phase change temperature is approximately 9°C to approximately 13°C. 48% to 58% by weight of inorganic salts; 1% to 3% by weight of a nucleating agent; A thickening agent in an amount of 1% to 3% by weight; and The PCM according to claim 1, comprising 40% to 45% by weight of water. [Claim 10] The inorganic salt is 30% to 36% by weight of sodium sulfate; and Containing 18% to 22% by weight of ammonium chloride, The PCM according to claim 9. [Claim 11] The PCM according to claim 9 or 10, wherein the nucleating agent comprises 1% to 3% by weight of sodium tetraborate. [Claim 12] The PCM according to any one of claims 9 to 11, wherein the thickening agent is a superabsorbent polymer. [Claim 13] The PCM according to claim 12, wherein the superabsorbent polymer is sodium polyacrylate and / or carbomer. [Claim 14] The phase change temperature is approximately 10°C to approximately 12°C, and the PCM is Approximately 33.6% by weight of sodium sulfate; Approximately 19.8% by weight of ammonium chloride; Approximately 2.0% by weight of sodium tetraborate; Approximately 2.0% by weight of sodium polyacrylate and / or carbomer; and The PCM according to claim 1, comprising approximately 42.6% by weight of water. [Claim 15] The aforementioned PCM has the following characteristics: At least approximately 160 kJ / kg of latent heat; Solid-state thermal conductivity of at least approximately 1.0 W / m·K; Thermal conductivity in the liquid phase of at least approximately 0.5 W / m·K; Specific heat capacity in the solid phase of at least approximately 1.4 kJ / kg·K; Specific heat capacity in the liquid phase at least approximately 2.0 kJ / kg·K; At least approximately 1500 kg / m 3 Density in the solid phase; and / or At least approximately 1400 kg / m 3 The PCM according to claim 14, having at least one density in the liquid phase. [Claim 16] The phase change temperature is approximately 23°C to approximately 27°C. 35% to 43% by weight of inorganic salts; 1% to 3% by weight of a nucleating agent; A thickening agent in an amount of 1% to 3% by weight; and The PCM according to claim 1, comprising 57% to 66% by weight of water. [Claim 17] The inorganic salt is 20% to 24% by weight of disodium phosphate; and The PCM according to claim 16, comprising 15% to 19% by weight of sodium carbonate. [Claim 18] The PCM according to claim 16 or 17, wherein the nucleating agent comprises 1% to 3% by weight of sodium tetraborate. [Claim 19] The PCM according to any one of claims 16 to 18, wherein the thickening agent is a superabsorbent polymer. [Claim 20] The PCM according to claim 19, wherein the superabsorbent polymer is sodium polyacrylate and / or carbomer. [Claim 21] The phase change temperature is approximately 24°C to approximately 26°C, and the PCM is Approximately 21.8% by weight of disodium phosphate; Approximately 16.7% by weight of sodium carbonate; Approximately 2.0% by weight of sodium tetraborate; Approximately 2.0% by weight of sodium polyacrylate and / or carbomer; and The PCM according to claim 1, comprising approximately 61.5% by weight of water. [Claim 22] The aforementioned PCM has the following characteristics: At least approximately 190 kJ / kg of latent heat; Solid-state thermal conductivity of at least approximately 1.0 W / m·K; Thermal conductivity in the liquid phase of at least approximately 0.5 W / m·K; Specific heat capacity in the solid phase of at least approximately 1.4 kJ / kg·K; Specific heat capacity in the liquid phase at least approximately 2.0 kJ / kg·K; At least approximately 1500 kg / m 3 Density in the solid phase; and / or At least approximately 1400 kg / m 3 The PCM according to claim 21, having at least one density in the liquid phase. [Claim 23] A heat exchanger (HEX), The system includes a plurality of plates, each plate defining at least one fluid channel extending across the plate, and the fluid channel exists for the flow of a heat transfer fluid. The aforementioned plurality of plates are arranged in a regular sequence, spaced apart from each other, and define a volume for receiving the PCM between adjacent plates. A heat exchanger (HEX) in which, when arranged in the aforementioned regular arrangement, a first flow path extending across a first plate is offset from a second flow path extending across a second plate adjacent to the first plate. [Claim 24] The HEX according to claim 23, wherein the fluid channel is configured such that, during use, turbulence of the heat transfer fluid having a Reynolds number of 4,000 to 7,500 is generated by the flow of the heat transfer fluid passing through the fluid channel at a target flow rate during use. [Claim 25] The HEX according to claim 24, wherein the Reynolds number is 4500 to 7000. [Claim 26] The HEX according to any one of claims 23 to 25, wherein each of the fluid channels has a polygonal cross-sectional shape. [Claim 27] The HEX according to any one of claims 23 to 26, wherein each of the fluid channels has a four-sided rhombic cross-sectional shape. [Claim 28] The HEX according to claim 27, wherein the four-sided rhombic cross-sectional shape has a pair of equal, opposing interior angles ranging from 46° to 89°. [Claim 29] The HEX according to claim 27 or 28, wherein the four-sided rhombic cross-sectional shape has short diagonal lengths of 15 mm to 20 mm and long diagonal lengths of 22 mm to 31 mm. [Claim 30] The HEX according to any one of claims 23 to 25, wherein each of the fluid channels has a circular or elliptical cross-sectional shape. [Claim 31] The HEX according to claim 30, wherein the circular cross-sectional shape has a diameter of 12 mm to 20 mm. [Claim 32] The HEX according to any one of claims 23 to 31, wherein the fluid channels extending across each plate are offset with respect to the outer circumference of the plate by one of two possible offset options, such that each plate is disposable within the HEX. [Claim 33] The HEX according to claim 32, wherein each plate is arranged in the HEX with an alternating offset option relative to adjacent plates such that the fluid flow path of each plate is offset relative to the fluid flow path of the adjacent plate. [Claim 34] The HEX according to any one of claims 23 to 33, wherein each fluid channel extends between an inlet and an outlet. [Claim 35] The HEX according to claim 34, comprising an inlet manifold configured to supply heat transfer fluid to at least some of the inlets during use, and an exhaust manifold configured to receive heat transfer fluid from at least some of the outlets during use. [Claim 36] The HEX according to any one of claims 23 to 35, wherein each of the fluid channels includes 14 to 18 straight sections extending over most of the length between the opposing edges of the plate, and the straight sections are interconnected by a plurality of curved sections positioned adjacent to the opposing edges of the plate. [Claim 37] The HEX according to claim 36, wherein the distance between the centers of two adjacent straight sections is 30 mm to 38 mm. [Claim 38] The HEX according to any one of claims 23 to 37, wherein the length of each fluid channel defined on each of the plates is 10.4 m to 13.1 m. [Claim 39] The HEX according to claim 24, wherein the target flow rate during use is 1,000 kg / hour to 5,000 kg / hour. [Claim 40] The HEX according to any one of claims 23 to 39, wherein the fluid channel is meandering. [Claim 41] It is a thermal cell, tank; HEX contained in the aforementioned tank; and A thermal cell containing a PCM housed in a tank, which performs heat exchange with the aforementioned HEX. [Claim 42] The thermal battery according to claim 41, wherein the PCM is defined in any one of claims 1 to 22. [Claim 43] The thermal battery according to claim 41 or 42, wherein the HEX is defined in any one of claims 23 to 40.

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