We are looking for a post-doc to join our research team and perform experiment on heterogeneous cavitation to explore the origin of cavitation nuclei.
The apparition of macroscopic bubbles inside a liquid either by boiling when temperature increases, from cavitation when pressure decreases or in supersaturated solution (large quantity of dissolved gas) originates from nano/microscopic bubbles, named nuclei. These nuclei are trapped in surface defects or stabilized by floating impurities. The nucleation, in this case, is called heterogeneous in opposition to the homogeneous nucleation occurring without pre-existing nuclei which required tremendous excitation, e.g. -140 MPa for the cavitation [1]. Although the nuclei are usually assumed to be formed during liquid immersion, we recently show that they can also spontaneously appear [2]. The aim of the overall project is to unravel the mechanism responsible for this generation of nuclei.
We are looking for a candidate with strong interest in experiments and coding (Python or Matlab) to control the setup. A fluid mechanics background, especially in diffusion and capillarity, is needed to interpret the results. Knowledge in acoustics is advisable but not mandatory.
During this postdoc funded by the ANR (CANURE), the candidate will acquire expertise in acoustics, cavitation, capillarity, wetting and dissolved gas transport. Moreover, the postdoc will gain strong experimental skills through the elaboration of the complex setup.
References:
[1] F. Caupin & E. Herbert, Cavitation in water : a review, C. R. Physique, 2006, 7, 1000-1017
[3] A. A. Atchley & A. Prosperetti, The crevice model of bubble nucleation. JASA, 1989, 86(3), 1065-1084

Cavitation bubbles appearing during few milliseconds on a surface after an acoustic pulse.
CONTACTS
Adrien Bussonnière, MSC, adrien.bussonniere@u-paris.fr
Valentin Leroy, MSC, valentin.leroy@u-paris.fr