Acoustic levitation of water droplets in an environmentally controlled chamber

该项目包括建造一种声学悬浮器，适用于在环境控制的室内悬浮微升或较小的水滴。使用该悬浮器的好处是防止水滴与其所在的任何底物发生任何相互作用。这些水滴将以受控的速度冷却，测量含有不同类型冰核颗粒的水滴的冻结温度，以及不同的盐浓度。任务包括建立一个合适的环境控制室，它可以冷却液滴，而不会产生诱导气流和因此的振荡，以及开发一种方法来引入液滴并检测它们何时冻结。随着液滴变小，还必须考虑到蒸发，并且必须控制湿度，以确保液滴持续冻结。

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.