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In the current energy shortage in the larger environment, the phase change material energy saving effect has been widely appreciated in the future energy strategy to occupy a very important position. As a kind of inorganic salt solution are more promising phase change materials, the phase change in the formation of hydrates, often there is a large degree of supercooling, reducing the overall efficiency of the storage system. To reduce the phase-change material undercooling, improve storage efficiency of the system, people are looking for a variety of external conditions to promote the nucleation and crystal growth, such as adding a nucleating agent, cold fingering, applied physics field (ultrasound, electromagnetic fields, magnetic field) and so on. Currently, the field of research on inorganic salt solution is still relatively small, the effect and mechanism of its action is no more unified conclusion, to carry out research in this area will help to basic research in this area to provide experimental data for engineering design reference. This paper studies the system at different constant magnetic field strength, the static magnetic field and alternating magnetic field, low temperature regenerator material undercooling and crystallization process. Material phase change process requires a stable visual environment, designed and built this complete bench, bench running good, detailed and reliable experimental data obtained. Application bench made of natural water, deionized water, 5% NaCl solution, 7% KCl solution, 5% NH4Cl solution, such as five kinds of working fluid at different magnetic field phase change cooling and crystallization process. Experimental results show that the magnetic field of water and the effect of the inorganic salt solution is a difference, the magnetic field for their crystallization temperature and crystallization time of less; magnetic field, the water will increase the degree of subcooling shorten asked subcooling , while the inorganic salt solution will reduce the degree of undercooling, shorter cooling times over, the magnetic field strength is, the more apparent this effect; magnetic aqueous solution of water and salt crystallization process are also different, the former will increase Large its crystal grain size, making the ice more fluffy and easier to melt, the latter will promote the growth of the crystal, the crystal formation to increase the particle size and crystal growth; addition, the magnetic field will be a solution of the metal cation cyclic structure ice play a certain extent. The difference is due to the magnetic field of water and aqueous solutions of inorganic salts caused by the different mechanism of action. Different types of magnetic effect of the above effects is different, constant magnetic field and a DC magnetic effect of the static magnetic field and its intensity is only relevant, but at the same intensity, the effect of the alternating magnetic field is most obvious, this is due to the alternating The size of the magnetic field and the direction of the force changes repeatedly, and capable of hydrogen bonding and ionic solution within the repeated cutting force, the magnetic force is applied to effect continuous.
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