Fluid-structure coupling of a microscopic beam with a non-uniform temperature.

What is it about?

In this article, we explore the fluid-structure coupling of a micrometer-sized cantilever in air, when it is locally heated. This is a complex problem to solve, as the temperature field results from heat conduction in the cantilever but also in the surroundings. It changes the properties of both the cantilever (Young's modulus mainly) and air (density and viscosity), leading to a non monotonic change of the mechanical beam response when temperature increases. we use analytical modelling, numerical simulations and experiments to propose a full picture of the problem.

Featured Image

Photo by White.Rainforest ∙ 易雨白林. on Unsplash

Photo by White.Rainforest ∙ 易雨白林. on Unsplash

Why is it important?

Thermal dissipation at microscopic scales is a tough problem: temperature variation scales are much smaller than available probes. Some advanced modelling is then required to understand the heat flow, and the consequences of the temperature field on the behavior of the system. We present here the case of a micro-cantilever heated in air, and how this affects its mechanical properties. Beyond this generic fluid structure study, this geometry is relevant in atomic force microscopy (especially for scanning thermal microscopy or dynamic modes operation), but also in general to study heated resonators in interaction with a fluid.