Development of apparatus for IceNucleation studies

  • Frederick Cook

Student thesis: Doctoral ThesisDoctor of Philosophy (PhD)

Abstract

Ice nucleation is an important process in many scientific fields. However, what makes a good icenucleator is still poorly understood. Therefore further experimental work is required to unravelhow certain surfaces can greatly reduce the barrier to ice nucleation. Here three ice nucleationexperimental methods are developed and discussed. The first is a pyroelectric thermal sensorfor automating cold plate array experiments. The thermal sensor is shown to reliably detectmicrolitre volume droplets of water freezing via the latent heat released. The effectivenessof the thermal sensor is demonstrated on a cold plate array experiment using a crystallineand glassy form of the same K-feldspar sample. Glassy K-feldspar is shown to be a poor icenucleator compared to the crystalline form. The second method is a device designed for repeatedlyfreeze/thaw cycling a0.5 mlsample, known as automated lag-time apparatus (ALTA). The coolingrate dependence of ice nucleation temperatures is demonstrated with the crystalline K-feldsparsample. The nucleation rates measured using a single sample freeze/thaw cycled in ALTA arecompared to the results using the pyroelectric thermal sensor. Finally, a set-up for acousticallylevitating water droplets in a temperature controlled chamber is described. The design process isdiscussed, as well as future modifications and improvements.
Date of Award11 May 2021
Original languageEnglish
Awarding Institution
  • The University of Bristol
SupervisorWalther Schwarzacher (Supervisor) & Adrian C Barnes (Supervisor)

Keywords

  • Ice Nucleation
  • Automated Lag Time Apparatus ALTA
  • Acoustic Levitation
  • K-feldspar
  • Pyroelectric PVDF

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