Direct Evidence of Charge-Induced Instability in Aerosol Droplets
Supervisor: Dr. Styliani (Stella) Constas
Can extend to MSc?: Yes
Project Description (Abstract):
Charged liquid droplets are unstable above a critical charge squared-to-volume ratio given by the Rayleigh limit. This instability arises from competing electrostatic and surface tension forces. The instability leads to formation of jets ejecting ions from the droplet surface. The Rayleigh instability appears in numerous applications that include sprays used in native mass spectrometry, manufacturing, and inkjet printing. It also plays a role in phenomena of quantum mechanical nature. The fission of charged droplets has been studied for approximately one and a half centuries starting from the seminal article of Lord Rayleigh (1882). However, for the first time we are able to perform large scale atomistic simulations and visualize the Rayleigh jets directly (S. Consta in https://arxiv.org/abs/2106.03756). The experiments cannot detect the fission mechanism exactly at the point it occurs. The only insight is obtained by continuum modelling, which is based on emerging hydrodynamic equations. The solutions of the continuum modelling are based on a number of assumptions and they have also to deal with singularities. Our atomistic modelling provides a reference model for assessing the assumptions of the continuum modelling. The student will perform atomistic simulations with a variety of solvents and assess the assumptions of the continuum modelling. The methods are described in https://arxiv.org/abs/2106.03756. The project is computational in nature so it is not affected by any changes that might take place in the academic program due to the pandemic.
References: S. Consta, https://arxiv.org/abs/2106.03756; Kwan, V., O’Dwyer, R., Laur, D., Tan, J., & Consta, S. (2021). J. Phys. Chem. A, 125(14), 2954.
