magnetocaloric adjective. Describing a reversible change in temperature of a material as a result of a change in magnetic field.
What is magnetocaloric effect? Magnetocaloric effect, MCE, is heating or cooling of a magnetic material upon application or removal of magnetic field. Materials that display a significant MCE, a temperature change a few degrees or more, are called magnetocaloric materials. A practically useful MCE is observed in ferromagnets around their Curie temperatures.
What are magnetocaloric materials? Magnetocaloric materials are metals endowing the magnetocaloric effect (MCE). Such materials include pure elements such as Gadolinium or alloys such as Lanthanum-iron-silicon (LaFeSi) or Iron-phosphorus (Fe2P).
How does a magnetocaloric material heat up? At the starting point (1) the magnetic material is in its paramagnetic state. The magnetocaloric material is placed in a thermally insulated (adiabatic) environment and the magnetic field is applied. The material heats up due to the above-mentioned magnetocaloric effect (2). Demonstration of active magnetic regeneration.
What is the magnetocaloric cycle? The magnetocaloric cycle is performed analogous to the refrigeration cycle by Carnot. In contrast to the conventional compressor-based Carnot cycle not the pressure but the magnetic field is increased and decreased. Similar to a gas compression cycle, the magnetic cooling process includes four steps.
magnetocaloric cooling
What is the magnetocaloric effect? Certain materials heat up, when brought into a magnetic field. This phenomenon is called the magnetocaloric effect (MCE). Materials endowing this effect are called magnetocaloric materials (MCM). Using the magnetocaloric effect, a magnetic cooling cycle near room temperature is possible.
How does a magnetocaloric material heat up? At the starting point (1) the magnetic material is in its paramagnetic state. The magnetocaloric material is placed in a thermally insulated (adiabatic) environment and the magnetic field is applied. The material heats up due to the above-mentioned magnetocaloric effect (2). Demonstration of active magnetic regeneration.
How does magnetic cooling occur in MCE? In MCE, the magnetic cooling or heating takes place when the material is subjected to an external magnetic field across its magnetic ordering temperature [252–256]. The MCE results in cooling when the magnetic entropy change ( Δ S m) is negative and vice versa.
What is magnetic cooling technology? The magnetic cooling technology is based on the ability of any magnetic material to change its temperature and entropy under the influence of a magnetic field. This ability manifests itself when compressing or expanding gas or steam in traditional refrigerators.
What is magnetocaloric effect?
What is magnetocaloric effect (MCE)? The magnetocaloric effect (MCE) is generally defined as the cooling or heating of magnetic materials with the variation of an externally applied magnetic field.
How does a magnetocaloric material heat up? At the starting point (1) the magnetic material is in its paramagnetic state. The magnetocaloric material is placed in a thermally insulated (adiabatic) environment and the magnetic field is applied. The material heats up due to the above-mentioned magnetocaloric effect (2). Demonstration of active magnetic regeneration.
How is the magnetocaloric effect used for refrigeration? The magnetocaloric effect (MCE) can be used for refrigeration by adiabatic demagnetization. The magnetic part of the entropy SM is lowered by adiabatic magnetization of a superparamagnetic material or a ferromagnetic material slightly above its Curie temperature ( Tc ). Thereby, the disorder of the magnetic spin system is greatly reduced.
What happens when materials are placed in magnetic fields? Some magnetic materials heat up when they are placed in a magnetic field and cool down when they are removed from a magnetic field. This is known as the magnetocaloric effect. This effect was discovered by E. Warburg in 1881 in pure iron. The size of the effect has been around .5 to 2°C per Tesla change in magnetic field.