Refrigeration Cycle

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There are two laws that are critical to comprehend the basic refrigeration cycle thermodynamics’ first law explains that energy is a basic concept of thermodynamics and one of the most important aspects of engineering analysis. Energy can be stored within systems in different macroscopic forms: gravitational potential energy, internal energy and kinetic energy. Energy can also be changed from one form to another and moved or distributed between systems. For closed systems, energy can be moved by heat transfer and work. The total amount of energy is stored in all transfers and transformations. Thermodynamics second law can enable us to better understand how the basic refrigeration cycle works. One of these laws expresses that heat always flows…show more content…
The utilization of the magnetic cooling at room temperature was essentially made conceivable with the discovery of materials which demonstrate the magnetocaloric effect at room temperature (particularly some uncommon metals and their composites (alloys)). The working principle of magnetic refrigerators depends on magnetocaloric effect, perceived as an adiabatic temperature change or isothermal entropy change. Let us carefully look at the schematic diagram of the theoretical magnetic refrigeration system in Figure 3 and its vapour compression counterpart. The conventional vapour compression system utilizes a compressor, two heat exchangers – a condenser and an evaporator, a throttling device. The refrigerant absorbs heat from the space to be refrigerated in the evaporator where it is transformed into vapour state. This vapour then moves to the compressor where its pressure and temperature is…show more content…
This is otherwise called adiabatic demagnetization by low temperature physicists. In that part of the overall refrigeration process, a reduction in the strength of an externally applied magnetic field permits the magnetic spaces of a picked (magneto caloric) material to become disoriented from the magnetic field by the perturbing action of the thermal energy (phonons) present in the material. If the material is separated so that no energy is allowed tomove into the material amid this time (i.e. an adiabatic process), the temperature drops as the spaces or domains absorb the thermal energy to play out their reorientation. The randomization of the domains happens in a comparable manner to the randomization at the Curie temperature, with the exception of that magnetic dipoles overcome a decreasing external magnetic field while energy stays constant, instead of magnetic domains being upset from internal ferromagnetism as energy is included. A standout example of the magnetocaloric effect is in the chemical element gadolinium and some of its alloys. Gadolinium's temperature is seen to increase when it enters certain magnetic fields. Gadolinium and its alloys are the best material accessible today for magnetic refrigeration close to room temperature
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