Experimental investigation of emulsion droplets impact on superheated surface using synchronized infrared thermography and high-speed visualization

Institute

Lehrstuhl für Thermodynamik (TUM-ED)

Type

Master's Thesis /

Content

 

Description

Topic：Experimental investigation of emulsion droplets impact on superheated surface using synchronized infrared thermography and high-speed visualization

 

Background:

Our understanding of the heat transfer mechanisms upon droplet impact is still very limited due to its multiscale nature and difficulties in obtaining reliable transient surface temperature distribution. As a non-intrusive method, infrared (IR) thermography has been widely used to obtain temperature contours. However, the current IR technique is limited by its measurement accuracy and spatiotemporal resolution, restricting its applications to stationary droplet or impact droplet under low heat fluxes conditions.

This work establishes a novel experimental platform, featuring a transparent ITO-coated sapphire substrate that enables simultaneous high-speed infrared thermography (2000 Hz, and 25 µm/ pixel) of the liquid-solid interface, synchronized with side- and bottom-view visualization (up to 10000 Hz, ~10 µm/pixel). The unique tri-modal approach (side-view, bottom-view, and IR thermography), with improved spatiotemporal resolution of the IR camera, provides unprecedent high resolution data at the impacting interface. Experiments will be performed for water-in-hexane emulsion droplets over a wide temperature range and Weber numbers.

 

Methods:

Experimental setup has already been built but still needs some improvements. 

Conduct experiments about emulsion droplets.

 

Objectives:

1. Investigate the impact dynamics and boiling behavior of water-in-hexane emulsion droplets on superheated surfaces.
2. Quantify the transient interfacial heat transfer mechanisms using synchronized infrared thermography and high-speed visualization.
3. Reveal the influence of emulsion composition on droplet-wall interactions and heat transfer performance.
4. Combine with previous work, this forms a structural framework for heat transfer during the impact of different droplets.

Previous work:

Already conducted some experiments based on water/ethanol/salt solution droplet, achieved some constructive conclusions.

The details could be referred to the published paper:

Yan, Yan, et al. "Experimental investigation of boiling regime transitions during ethanol droplets impact using synchronized infrared thermography and high-speed visualization." International Journal of Heat and Mass Transfer 267 (2026): 128975. https://doi.org/10.1016/j.ijheatmasstransfer.2026.128975

Requirements

- MSc student in thermo, heat transfer, thermodynamics, chemistry or related field.

- Experience with experiments, high speed cameras, data-processing tool (e.g. python) would be better.

Possible start

immediately

Contact

M.Sc. Yan Yan
Room: 5507.EG.729
Phone: +49 89 289 16193
y.yantum.de