几种氧化物纳米流体强化传热性能研究

Study on Enhanced Heat Transfer of Several Oxide Nanofluids

以水/乙二醇混合液为基液,加入Al_2O_3,MgO和ZnO纳米颗粒配制得到纳米流体。在自制对流传热性能测试平台上进行基液及纳米流体传热性能的测试。结果表明:同基液相比,随流体流速增大,Al_2O_3纳米流体的传热系数变化不明显,MgO和ZnO纳米流体的传热系数均有提高。层流状态下,随雷诺数增大,三种纳米流体的传热系数都不断增大。当雷诺数为1400时,MgO纳米流体传热系数提高最大,达到了244.0%。良好的强化传热性能,使得氧化物纳米流体今后有望应用在发动机冷却系统中。

With mixture of distilled water and ethylene glycol as base fluid,nanofluids containing Al_2O_3,MgO and ZnO nanoparticles were prepared.The convective heat transfer performances of the nanofluids were investigated on self-made testing system.The experimental results showed that the heat transfer coefficients of MgO and ZnO nanofluids were both increased with flow rates increasing in comparison to base fluid.No distinct enhancements were achieved for Al_2O_3 nanofluids. Under laminar flow state,the heat transfer coefficients of all nanofluids monotonically increased with Reynolds numbers augmenting.The maximum increase of heat transfer coefficients of MgO nanofluids reached 224.0%.Based on excellent enhanced heat transfer performances,oxide nanofluids have potential application as an alternative for conventional engine coolant.