Regenerator for a magnetic heat exchanger and heat exchanger

Patent metadata

Field	Value
Publication number	US-12480690-B2
Application number	US-202318446767-A
Country	US
Kind code	B2
Filing date	Aug 9, 2023
Priority date	Aug 9, 2022
Publication date	Nov 25, 2025
Grant date	Nov 25, 2025

Abstract

A regenerator for a magnetic heat exchanger is provided. The regenerator comprises a housing having a chamber, an inlet and outlet for a working medium, and a chamber volume V. At least one magnetocalorically active component is arranged in the chamber between the inlet and the outlet and has at least one inner flow channel with a hydraulic diameter d hyd . The volume of the chamber not occupied by the magnetocalorically active component provides at least one bypass flow channel, both the inlet and the outlet being reached from the at least one bypass flow channel, and this bypass flow channel having a hydraulic diameter D, where D>d hyd . The at least one inner flow channel of the magnetocalorically active component is in flow communication with the bypass flow channel. The magnetocalorically active component and the at least one bypass flow channel are arranged parallel to one another.

First claim

The invention claimed is:

1 . A regenerator for a magnetic heat exchanger, comprising:
a housing having a chamber, an inlet for a working medium and an outlet for the working medium, the chamber having a volume V, at least one magnetocalorically active component that is arranged in the chamber between the inlet and the outlet and that has at least one inner flow channel with a hydraulic diameter d hyd ,
wherein the volume of the chamber that is not occupied by the magnetocalorically active component provides at least one bypass flow channel, wherein both the inlet and the outlet are reached from the at least one bypass flow channel, and this bypass flow channel has a hydraulic diameter D, where D>d hyd and wherein the at least one inner flow channel of the magnetocalorically active component is in flow communication with the bypass flow channel,
wherein a flow direction of the working medium extends from the inlet to the outlet, and the magnetocalorically active component and the at least one bypass flow channel are arranged in parallel with one another with respect to the direction of flow.

2 . A regenerator according to claim 1 , wherein a shortest length s of the at least one inner flow channel is shorter than a length L of the magnetocalorically active component measured in the direction of the mean flow direction of the working medium.

3 . A regenerator according to claim 1 , wherein the magnetocalorically active component comprises a total cross-sectional area a that is smaller than an inner cross-sectional area A of the chamber so that the bypass flow channel is formed between the magnetocalorically active component and the chamber.

4 . A regenerator according to claim 1 , wherein the bypass flow channel is surrounded by the magnetocalorically active component.

5 . A regenerator according to claim 1 , wherein the bypass flow channel comprises the form of at least one gap between the housing and the magnetocalorically active component and/or at least one recess in the cross section of the magnetocalorically active component.

6 . A regenerator according to claim 1 , wherein the magnetocalorically active component comprises a plurality of sub-units, and the bypass flow channel comprises the form of at least one gap created between the sub-units.

7 . A regenerator according to claim 6 , wherein the sub-units are arranged adjacent to one another and transverse to the flow direction of the working medium in the chamber and/or are arranged one on top of another and parallel to the flow direction of the working medium in the chamber.

8 . A regenerator according to claim 1 , further comprising a macroscopic porosity ε macro that is calculated by dividing the volume Vbs of the bypass flow channel by the volume V of the chamber and a microscopic porosity ε micro that is calculated by dividing volume Vis of the inner flow channels divided by the volume Vb of the magnetocalorically active component, where 10%<ε macro <50% and 10%<ε micro <50% and 19%≤ε total ≤75%, wherein the total porosity ε total is calculated using the formula ε total =(Vbs+Vis)/V.

9 . A regenerator according to claim 1 , wherein the magnetocalorically active component is formed by individual magnetocalorically active particles that are connected fixedly together, wherein the at least one inner flow channel is formed between the particles.

10 . A regenerator according to claim 9 , wherein the magnetocalorically active particles are connected fixedly together by means of a magnetocalorically passive material.

11 . A regenerator according to claim 10 , wherein the magnetocalorically passive material is a solder or an adhesive.

12 . A regenerator according to claim 9 , wherein the individual particles are sintered together.

13 . A regenerator according to claim 9 , wherein the mean diameter of the particles is <500 μm.

14 . A regenerator according to claim 1 , wherein the magnetocalorically active component has the form of a plurality of magnetocalorically active sub-units, and the at least one inner flow channel is formed between these sub-units.

15 . A regenerator according to claim 14 , wherein the sub-units are plate-shaped and stacked one on top of another and each has at least one recess that forms the inner flow channel.

16 . A regenerator according to claim 14 , wherein the magnetocalorically active sub-units are connected fixedly together by a magnetocalorically passive material.

17 . A regenerator according to claim 16 , wherein the magnetocalorically passive material is a solder or an adhesive.

18 . A regenerator according to claim 14 , wherein the sub-units have the form of sintered particles.

19 . A regenerator according to claim 1 , wherein the hydraulic diameter d hyd of the inner flow channels is <500 μm and the hydraulic diameter D of the bypass flow channels is >500 μm.

20 . A regenerator according to claim 1 , wherein the magnetocalorically active component comprises a magnetocalorically active material with a composition of La 1-a —R a (Fe 1-x-y T y M x ) 13 H x C b , M is Si and optionally Al, T is one or more of the elements from the group comprising Mn, Co, Ni, Ti, V and Cr and R is one of more the elements Ce, Nd, Y and Pr, where 0≤a≤0.5, 0.05≤x≤0.2, 0.003≤y≤0.2, 0≤z≤3 and 0≤b≤1.5.

21 . A heat exchanger, comprising
at least one regenerator according to claim 1 , a working medium that flows through the inner flow channel and the bypass flow channel when the heat exchanger is in operation, a switchable magnetic field source for generating a magnetic field at the component of the regenerator.

22 . A heat exchanger according to claim 21 , wherein at least two regenerators are provided, and these regenerators have at least two different Curie temperatures.

23 . A heat exchanger according to claim 22 , wherein the at least two regenerators are connected in series in such a manner as to provide a cascade with increasing Curie temperatures.

24 . A heat exchanger according to claim 21 , wherein the heat exchanger is configured according to the heat pipe principle and, in addition has a condenser that is in flow communication with the outlet of the housing and an evaporator that is in flow communication with the inlet of the housing.

25 . A heat exchanger according to claim 24 , further comprising an adjustable thermal connection between two regenerators.

26 . A heat exchanger according to claim 25 , wherein the adjustable thermal connection comprises a pressure valve or a thermo valve.

27 . A heat exchanger according to claim 21 , wherein the heat exchanger is configured according to the active magnetocaloric regenerator principle.

28 . A regenerator for a magnetic heat exchanger, comprising:
a housing having a chamber, an inlet for a working medium and an outlet for the working medium, the chamber having a volume V, at least one magnetocalorically active component that is arranged in the chamber between the inlet and the outlet and has at least one inner flow channel with a hydraulic diameter d hyd ,
wherein the volume of the chamber that is not occupied by the magnetocalorically active component provides at least two bypass flow channels that each have a hydraulic diameter D, where D>d hyd , wherein the at least one inner flow channel of the magnetocalorically active component is in flow communication with at least two of

Assignees

• Vacuumschmelze Gmbh & Co Kg

Inventors

• Katter Matthias
• Barcza Alexander
• Vieyra Villegas Hugo Abdiel
• Bartholomé Kilian
• Maier Lena Maria
• Corhan Patrick
• Näher Manuel
• Vogel Christian

Classifications

• F25B2321/002

  by using magneto-caloric effects · CPC title

• H01F1/0557

  sintered · CPC title

• F28F2265/02

  in the form of screens or covers · CPC title

• F28F2255/18

  sintered · CPC title

• F28D2021/0033

  for cryogenic applications · CPC title