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通过实验研究了相变微胶囊颗粒与去离子水的混合溶液在内径1mm紫铜圆管内换热特性。结果表明:在雷诺数Re=300~1 000,去离子水中加入相变微胶囊颗粒可以明显降低流体的出口温度,且降低的幅度随相变微胶囊悬浮液浓度的增加而增大,在实验条件下,与去离子水相比,相变微胶囊悬浮液出口温度最高可降低16.17%,因此在换热器传热量不变、流体出入口温度相同的情况下,以相变微胶囊悬浮液作为传热介质,最大可减小流量20%,从而输送管路的尺寸、输送泵功的功耗也随着减小;去离子水中加入相变微胶囊颗粒,能够明显换热,强化的幅度随Re及相变微胶囊悬浮液浓度的增加而增大,在实验条件下,与去离子水相比相变微胶囊悬浮液平均换热系数最高可提高39.5%。因此,在换热器传热量不变的情况下,以相变微胶囊悬浮液作为传热介质,传热面积最大可以减小28.3%,从而节约了初投资。
The heat transfer characteristics of a mixed solution of phase change microcapsule particles and deionized water in a 1 mm diameter copper tube were experimentally studied. The results show that when the Reynolds number Re = 300-1 000, phase change microcapsule particles are added in deionized water, the exit temperature of the fluid can be obviously decreased, and the decreasing amplitude increases with the concentration of the phase-change microcapsule suspension. In the experiment Under the conditions, compared with deionized water, the phase transition microcapsule suspension outlet temperature can be reduced by up to 16.17%, so the same heat exchanger, fluid inlet and outlet temperatures at the same circumstances, the phase change microcapsule suspension as Heat transfer medium, the maximum flow rate can be reduced by 20%, so the size of the transmission pipeline, power transmission pump power also decreases; adding deionized water phase change microcapsule particles, can significantly heat, enhanced with the Re and the phase change microcapsule concentration increased. Under the experimental conditions, the average heat transfer coefficient of the phase-change microcapsule suspension was 39.5% higher than that of deionized water. Therefore, when the heat transfer of the heat exchanger is constant, the heat transfer area can be reduced by 28.3% with phase-change microcapsule suspension as the heat transfer medium, thus saving the initial investment.