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采用两步法制备不同质量分数的 SiO2纳米流体，测量其粒度、Zeta电位以表征流体的悬浮稳定性，同时实验测量不同温度、不同粒径纳米流体的导热系数，结果表明，超声振动时间为3h时，纳米流体悬浮稳定性可达到实验要求，室温20℃，质量分数5%的纳米流体导热系数比基液增加6.8%；针对纳米流体冷却菲涅尔高倍聚光砷化镓电池的冷却性能，从流场和温度场相互配合的角度引入场协同角，评价不同质量分数、不同纳米流体冷却砷化镓电池的协同性，结果表明，场协同角随着纳米颗粒粒径的减小、质量分数的增加而减小，其传热强化效果增强。“,”ABSTRACT:SiO2 nanofluids with different mass fractions were prepared via two step method in order to investigate their thermophysical characteristics and the convective heat transfer mechanism. The particle size and the Zeta potential of SiO2 nanofluids were also measured to characterize the suspension stability of the fluid. And the coefficients of thermal conductivity of nanofluids were studied with different temperature and particle sizes. The results indicate that after 3h with the ultrasonic vibration the suspension stability of the nanofluids satisfy with experiment requirement, and the thermal conductivity of the nanofluids with 5% mass fraction increased 6.8% which compared with the base fluid when the room temperature is 20℃. Meanwhile, the efficiency with the different nanofluids cooling Fresnel high concentrated performance on the gallium arsenide batteries is evaluated with the field synergy angle,which included by the velocity field and the temperature field. The results show that the field synergy angle is reduced along with the decreases of the nano particle size and increases of the mass fraction of the fluid, and their heat transfer strengthening effect is enhanced.