Acoustic levitation of water droplets in an environmentally controlled chamber

该项目涉及建造一个声学悬浮器，适用于在一个环境受控的腔室中悬浮微升或更小的水滴。拥有悬浮器的好处是防止水滴与它们所处的任何基底发生任何相互作用。水滴将以受控的速度冷却，测量水滴与不同类型的冰成核颗粒的冻结温度，以及不同的盐浓度。任务包括建造一个合适的环境控制室，可以冷却液滴而不会引起气流和振荡，以及开发一种方法来引入液滴并检测它们何时冻结。随着水滴变小，蒸发也必须考虑在内，湿度必须控制，以确保水滴持续足够长的时间冻结。

This project involves building an acoustic levitator suitable for levitatingmicrolitre or smaller water droplets in an environmentally controlled chamber.The benefit of having the levitator is to prevent any interactions the dropletswould have with any substrate they were sitting on. The droplets will becooled at a controlled rate, with measurements being made on the freezingtemperatures of water droplets with different types of ice nucleating particles,as well as different salt concentrations. Tasks involve building a suitableenvironmentally controlled chamber which can cool the droplets withoutinducing air currents and therefore oscillations, as well as developing amethod to introduce droplets and detect when they have frozen. As thedroplets get smaller evaporation will also have to be taken into account, andthe humidity will have to be controlled to ensure the droplets last longenough to freeze.