Nanofluid suspensions have become the working fluid of the nowadays’ heat transfer implementations due to their distinguished behaviours on convective heat transfer. Boiling heat transfer which provides high heat fluxes is a kind of convective heat transfer, and thereby, thermal performance of a such mechanism largely depends on the working fluid type utilized. In this study, heat transfer characteristics of the two different aqueous nanofluid suspensions, namely kaolin-distilled water and bauxite-distilled water, under saturated boiling conditions were numerically investigated. Using Computational Fluid Dynamics approach and time-dependent Volume-of-Fluid multiphase model, vapour volume fractions and velocity vectors in fluid of interest were specified both distilled water and the prepared nanofluid suspensions. For each working fluid, the beginning time of the boiling was determined to illustrate how nanoparticles affect this phenomenon. Besides, the influences of the heating power applied to the heater on such boiling characteristics of bubble shape, bubble generation and the quantity were investigated. The boiling regimes of transition boiling and film boiling that cannot be encountered in operation were demonstrated by numerical simulations. The numerical results show that nanoparticles doped into the distilled water decreased the beginning time of the boiling compared to distilled water, and remarkably affected the bubble generation and departure characteristics.

中文翻译：

---

高岭土和铝土矿纳米流体的核池沸腾传热特性的模拟

纳米流体悬浮液由于其在对流换热方面的杰出表现，已成为当今传热实施的工作流体。提供高热通量的沸腾传热是对流传热的一种，因此，这种机构的热性能在很大程度上取决于所使用的工作流体的类型。在这项研究中，数值研究了两种不同的纳米流体水性悬浮液，即高岭土蒸馏水和铝土矿蒸馏水在饱和沸腾条件下的传热特性。使用计算流体动力学方法和随时间变化的流体体积多相模型，可以在蒸馏水和制备的纳米流体悬浮液中指定目标流体中的蒸汽体积分数和速度矢量。对于每种工作液，确定沸腾的开始时间以说明纳米颗粒如何影响该现象。此外，研究了施加在加热器上的加热功率对气泡形状，气泡产生和数量等沸腾特性的影响。通过数值模拟证明了操作中无法遇到的过渡沸腾和薄膜沸腾的沸腾方式。数值结果表明，与蒸馏水相比，掺入蒸馏水中的纳米颗粒减少了沸腾的开始时间，并且显着影响了气泡的产生和离开特性。研究了气泡的产生和数量。通过数值模拟证明了在操作中不能遇到的过渡沸腾和膜沸腾的沸腾状态。数值结果表明，与蒸馏水相比，掺入蒸馏水中的纳米颗粒减少了沸腾的开始时间，并且显着影响了气泡的产生和离开特性。研究了气泡的产生和数量。通过数值模拟证明了在操作中不能遇到的过渡沸腾和膜沸腾的沸腾状态。数值结果表明，与蒸馏水相比，掺入蒸馏水中的纳米颗粒减少了沸腾的开始时间，并且显着影响了气泡的产生和离开特性。