Simulation of the spreading of a gas-propelled micro-droplet upon impact on a dry surface using a lattice-Boltzmann approach
Simulation of the spreading of a gas-propelled micro-droplet upon impact on a dry surface using a lattice-Boltzmann approach
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DOI：
10.1063/1.4989546
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发表时间：
2017-07
影响因子：
4.6
通讯作者：
M. Ebrahim;A. Ortega;N. Delbosc;M. Wilson;J. Summers
中科院分区：
文献类型：
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作者：
M. Ebrahim;A. Ortega;N. Delbosc;M. Wilson;J. Summers
喷雾冷却是一种很有前途的高热流密度电子器件冷却方法。根据喷嘴的类型，喷雾冷却可以分为单相或两相。在后者中，已知其更有效，二次气体用于进一步加压液体并以较高速度形成较小液滴。还假设气体通过在液滴自由表面上施加法向力和切向力来辅助扩散阶段，这增加了液滴冲击的复杂流体动力学。此外，喷雾冷却中液滴尺寸的数量级为10 - 6 m，从而引入了迄今为止尚未很好理解的低韦伯数和雷诺数的冲击状态。采用三维格子Boltzmann方法模拟了大气和滞止气流中单个微液滴对干表面的撞击。两种情况下进行了密切的比较，并提出了相关的瞬时蔓延直径。与最近的Fl...
Spray cooling is one of the most promising methods of cooling high heat flux electronics. Depending on the type of the nozzle, spray cooling can be categorized as single-phase or two-phase. In the latter, which is known to be more effective, a secondary gas is used to further pressurize the liquid and form smaller droplets at higher velocities. The gas is also assumed to assist the spreading phase by imposing normal and tangential forces on the droplet free surface which adds to the complicated hydrodynamics of the droplet impact. Moreover, the order of magnitude of droplet size in spray cooling is 10−6 m, thereby introducing a low Weber and Reynolds numbers’ impact regime which heretofore has not been well understood. A 3D lattice Boltzmann method was implemented to simulate the impact of a single micro-droplet on a dry surface both in ambient air and under a stagnation gas flow. Two cases were closely compared and correlations were proposed for the instantaneous spreading diameter. Contrary to recent fi...