纳米流体固着液滴蒸发等流动与传热问题的LBM分析

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1、大连理工大学博士学位论文纳米流体固着液滴蒸发等流动与传热问题的LBM分析姓名：郭亚丽申请学位级别：博士专业：热能工程指导教师：沈胜强;李维仲20090301纳米流体固着液滴蒸发等流动与传热问题的LBM分析到了该过程中纳米流体液滴的动态演变，表明蒸发过程出现基部直径保持不变液滴高度降低的销联阶段和液滴后退的解销阶段，最终形成纳米颗粒的环形沉积，并且纳米颗粒大小环形沉积具有影响，探讨了纳米粒子在纳米液滴蒸发中的作用机理。实验观察了纳米流体固着液滴在水平加热平面蒸发的过程，并与模拟结果作出比较。通过液滴形状分析法，实验观测了

2、乙醇一铝纳米流体液滴和乙醇液滴的蒸发过程，由实验数据可明显看出与模拟结果相一致的特征，即蒸发经历了销联和解销两个阶段。在销联阶段，同纯乙醇液滴相比，由于纳米流体的粘性较大，使其蒸发速率降低。纳米粒子在液滴边缘的沉积改变了固液界面张力，这使接触角增大，故纳米流体液滴的初始接触角比纯乙醇的大，同时液滴开始后退的临界接触角纳米流体的比纯乙醇的小，所以纳米流体液滴保持销联的阶段比乙醇的长，即乙醇的后退阶段长，而该阶段的蒸发速率急剧降低，故对相同体积的液滴而言，纳米流体的整体蒸发速率比纯乙醇的高。将模拟计算的结果与实验结果进行了

3、比较，两者高度一致，表明了模拟的正确性。关键词：格子BoItzmann方法；纳米流体；液滴；蒸发；销联大连理工大学博士学位论文StudyofFlowandHeatTransferintheProcesssuchasEvaporationofNanofluidSessileDropletwithLBMAbstractTheheattransferperformanceofthefluidisthemainfactorthathinderstheheattransferef!ficiency．highcompactness

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7、eheattransfersubstance，nanofluidcaneffectivelyenhancetheheattransferperformanceofthedeviceandmakethedevicemorecompactwithhighe伍ciency．Theevaporationofnanofluiddropletwillbcwidelyappliedinthefieldofvehicle，spaceflight，voyage，shippingandelectron。Thehydrokinetics，t

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