Belšak Grega, Bajt Saša, Šarler Božidar
Laboratory for Fluid Dynamics and Thermodynamics, Faculty of Mechanical Engineering University of Ljubljana, 1000 Ljubljana, Slovenia.
Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany.
Materials (Basel). 2021 Jun 28;14(13):3614. doi: 10.3390/ma14133614.
The purpose of this work is to determine, based on the computational model, whether a mixture of a binary liquid is capable of producing longer, thinner and faster gas-focused micro-jets, compared to the mono-constituent liquids of its components. Mixtures of water with two different alcohols, water + ethanol and water + 2-propanol, are considered. The numerical study of pre-mixed liquids is performed in the double flow focusing nozzle geometry used in sample delivery in serial femtosecond crystallography experiments. The study reveals that an optimal mixture for maximizing the jet length exists both in a water + ethanol and in a water + 2-propanol system. Additionally, the use of 2-propanol instead of ethanol results in a 34% jet length increase, while the jet diameters and velocities are similar for both mixtures. Pure ethanol and pure 2-propanol are the optimum liquids to achieve the smallest diameter and the fastest jets. However, the overall aim is to find a mixture with the longest, the smallest and the fastest jet. Based on our simulations, it appears that water + 2-propanol mixture might be slightly better than water + ethanol. This study reveals the dominant effect of liquid viscosity on the jet breakup process in a flow focusing nozzles operated under atmospheric conditions.
这项工作的目的是基于计算模型，确定与二元液体各组分的单一组分液体相比，二元液体混合物是否能够产生更长、更细且速度更快的气体聚焦微射流。考虑了水与两种不同醇类（水 + 乙醇和水 + 2 - 丙醇）的混合物。预混合液体的数值研究是在串行飞秒晶体学实验中用于样品输送的双流聚焦喷嘴几何结构中进行的。研究表明，在水 + 乙醇和水 + 2 - 丙醇体系中都存在使射流长度最大化的最佳混合物。此外，用2 - 丙醇代替乙醇会使射流长度增加34%，而两种混合物的射流直径和速度相似。纯乙醇和纯2 - 丙醇是实现最小直径和最快射流的最佳液体。然而，总体目标是找到一种具有最长、最小且最快射流的混合物。基于我们的模拟，水 + 2 - 丙醇混合物似乎可能比水 + 乙醇稍好。这项研究揭示了在大气条件下运行的流动聚焦喷嘴中，液体粘度对射流破碎过程的主导作用。
