Evaporation heat and mass transfer in open microchannels was investigated using pure liquids (ethanol, deionized water and butanol), an ordinary (non-self-rewetting) mixture (5% v/v ethanol/water mixture) and a self-rewetting fluid (5% v/v butanol/water mixture). The applied heating power ranged from 0 mW to 282.76 mW (giving heat fluxes from 0 W/m² to 4501 W/m²) with wall temperatures ranging from 24 °C to 95 °C. When the microchannel had no external heating, diffusion was found to be the main mechanism of mass transfer. With external heating, the diffusion model underestimated the experiment results, and buoyancy-driven convection may account for this. Evaporation rates remain high for the self-rewetting fluid even when the meniscus recedes significantly (by 6 times the inner diameter) in the microchannel under heating conditions. Additionally, the self-rewetting fluid showed the highest conduction rate in the axial direction in high heating power conditions. Meniscus-wall contact angles and flow visualizations were obtained for various heating rates. The “contact angle shift” phenomenon of the self-rewetting fluid was observed. Marangoni-induced convection in the microchannel accounts for the mechanism of better heat and mass transfer as well as the “contact angle shift” phenomenon for the self-rewetting fluid.

使用纯液体（乙醇，去离子水和丁醇），普通（非自润湿）混合物（5％v / v乙醇/水混合物）和自润湿流体（ 5％v / v丁醇/水混合物）。施加的加热功率范围为0 mW至282.76 mW（给出的热通量为0 W / m ²至4501 W / m ²），壁温范围为24°C至95°C。当微通道没有外部加热时，发现扩散是传质的主要机理。在外部加热的情况下，扩散模型低估了实验结果，而浮力驱动的对流可能是造成这种情况的原因。即使在加热条件下，微通道中弯液面明显后退（内径的6倍），自润湿流体的蒸发率仍然很高。另外，在高热功率条件下，自润滑流体在轴向上显示出最高的传导率。获得了各种加热速率的弯月面-壁接触角和流动可视化。观察到自润湿液体的“接触角偏移”现象。