Hydrodynamic cavitation has been widely applied in micro-fluidic systems. Cavitating flow characteristics are closely related to the fluid properties. In this paper, the cavitation characteristics of Cu nano-fluid in micro-channels were numerically investigated and compared with those of the deionized (DI) water. The mathematical model was verified by comparing the numerical results with the experiment observation. The curved orifice (R = 0.3 mm) was found to have the highest efficiencies of cavitation for both fluids. With the increase of inlet pressure, cavitating jet lengths of the two fluids significantly increased. While, the cavitating jet length of the nano-fluid was shorter than that of the DI water at the same inlet pressure. The cavitation inception number of the DI water and nano-fluid were approximately 0.061 and 0.039, respectively. The results indicate that the nano-particles played negative effects on the cavitation inception. In addition, with the decrease of outlet pressure, the cavitation strength gradually increased and the mass flow rate remained nearly unchanged at the same time.

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纳米流体与去离子水在微通道中空化特性的比较研究

流体动力空化已广泛应用于微流体系统。空化流动特性与流体特性密切相关。本文对铜纳米流体在微通道中的空化特性进行了数值研究，并与去离子水进行了比较。通过将数值结果与实验观察结果进行比较，验证了数学模型。发现弯曲孔口（R = 0.3毫米）对两种流体的空化效率最高。随着入口压力的增加，两种流体的空化射流长度显着增加。同时，在相同的入口压力下，纳米流体的空化射流长度比去离子水的空化射流长度短。去离子水和纳米流体的空化起始数分别约为0.061和0.039。结果表明，纳米颗粒对空化开始起负面作用。此外，随着出口压力的降低，空化强度逐渐增加，同时质量流量几乎保持不变。