Apparatus for real-time acoustic imaging of Rayleigh-Benard convection

TL;DR

This paper presents a novel apparatus that uses advanced ultrasound technology to enable real-time acoustic imaging of convection patterns in opaque fluids, validated with silicone oil and ferrofluid.

Contribution

It introduces a new method for visualizing convective flow in opaque fluids using ultrasound imaging, expanding capabilities beyond optical techniques.

Findings

Successful imaging of convection rolls in silicone oil.

Effective visualization of convection in ferrofluid.

Validation of the apparatus with real fluid experiments.

Abstract

We have designed and built an apparatus for real-time acoustic imaging of convective flow patterns in optically opaque fluids. This apparatus takes advantage of recent advances in two-dimensional ultrasound transducer array technology; it employs a modified version of a commercially available ultrasound camera, similar to those employed in non-destructive testing of solids. Images of convection patterns are generated by observing the lateral variation of the temperature dependent speed of sound via refraction of acoustic plane waves passing vertically through the fluid layer. The apparatus has been validated by observing convection rolls in both silicone oil and ferrofluid.