Birkin P R, Foley T M, Truscott T T, Merritt A, Martini S
Chemistry, University of Southampton, Southampton, S017 1BJ, UK.
Department of Mechanical and Aerospace Engineering, Utah State University, Logan, UT 84322-4130, USA.
Phys Chem Chem Phys. 2017 Mar 1;19(9):6785-6791. doi: 10.1039/c6cp08149e.
Cavitation clusters and streamers are characterised in lipid materials (specifically sunflower oil) and compared to water systems. The lipid systems, which are important in food processing, are studied with high-speed camera imaging, laser scattering and pressure measurements. In these oils, clusters formed at an aged (roughened) tip of the sound source (a piston like emitter, PLE) are shown to collapse with varied periodicity in relation to the drive amplitude employed. A distinct streamer (an area of increased flow emanating from the cavitation cluster) is seen in the lipid media which is collimated directly away from the tip of the PLE source whereas in water the cavitation plume is visually less distinct. The velocity of bubbles in the lipid streamer near the cluster on the order of 10 m s. Local heating effects, within the streamer, are detected using a dual thermocouple measurement at extended distances. Viscosity, temperature and the outgassing within the oils are suggested to play a key role in the streamer formation in these systems.
研究了脂质材料（特别是葵花籽油）中的空化簇和流光，并与水系统进行了比较。在食品加工中很重要的脂质系统，通过高速摄像机成像、激光散射和压力测量进行研究。在这些油中，在声源（活塞式发射器，PLE）老化（粗糙化）的尖端形成的簇显示出相对于所采用的驱动振幅以不同的周期坍塌。在脂质介质中可以看到一条明显的流光（从空化簇发出的流量增加的区域），它直接从PLE源的尖端准直向外，而在水中，空化羽流在视觉上不那么明显。脂质流光中靠近簇的气泡速度约为10米/秒。使用双热电偶在较远的距离进行测量，检测到流光内的局部加热效应。油中的粘度、温度和脱气被认为在这些系统中流光的形成中起关键作用。
