石墨-水纳米流体对流换热特性的实验研究

使用自行设计的测量纳米流体流动与对流换热性能的实验装置,测量了含有不同体积分数纳米石墨的石墨-水纳米流体雷诺数在3 000~6 500范围内的对流换热系数。实验结果表明:石墨纳米颗粒的加入提高了水的对流换热系数;石墨纳米颗粒在水中的体积分数与对流换热系数近似呈线性关系;努塞尔数Nu随着雷诺数的增大近似线性增大;流动状态下的纳米粒子本身的无规则运动和热散射对对流换热系数的提高有显著影响。

Experimental Investigation on Convective Heat Transfer of the Graphite-water Nanofluid

Convective heat transfer coefficient was measured at different volume fraction of graphite-water nano-fluids with Re in scope of 3 000—6 500 by using self-designed nano-fluid flow and convective heat transfer performance of the experimental device.The experimental results showed that graphite nano-particles improved the convection heat transfer coefficient of water;the volume fraction of graphite nano-particles in water and convective heat transfer coefficient is nearly linear relationship;Nu number increases linearly with Re increasing;the random motion of nano-particles at flow state and the thermal scattering have a significant effect on increase of convective heat transfer coefficient.