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Benchmark Configuration Immersed Body – Forced Wetting and De-Wetting on Complex Surfaces

The overarching goal of the project is to delineate the physics of thin film evaporation, so-called microlayers, which plays a significant role in liquid-vapour phase change processes, such as pool boiling, flow boiling in microchannels, printed electronics, semiconductor industry, and heat exchangers among others. The microlayer forms when a thin film of liquid is trapped underneath a sufficiently fast growing vapour bubble. The evaporation of this trapped liquid (microlayer evaporation) elevates the heat flux and also contributes to the overall bubble growth. However the development of a microlayer is not sufficiently investigated so far and hencejust barely understood.

Accordingly, this project focuses on the detailed investigation of parameters which contributes to the microlayer formation, such as the wall material, the fluid properties, the wall superheat, and the dewetting velocity among others. A generic experimental setup is therefore used to address the influence of the above-mentioned parameters completely decoupled, which is otherwise difficult to achieve in a boiling scenario. The dynamic contact angle is measured with a high-speed camera, while the local temperature field at the fluid-wall interface is recorded with an infrared camera.

The experiments conducted herein are used to validate the numerical models and to examine the novel surface-fluid combinations relevant to industries. The CRC 1194 provides an excellent interdisciplinary platform for scientists from various fields such as Physics, Chemistry, Mathematics, and Engineering to collaborate and bridge the existing gap in the literature.

CRC 1194 website

• Sinha, K. N. R., Kumar, V., Kumar, N., Thakur, A., and Raj, R., 2021, “Deep learning the sound ofboiling for advance prediction of boiling crisis,” Cell Reports Physical Science, 2, pp. 100382, https://doi.org/10.1016/j.xcrp.2021.100382.
• Sinha, K. N. R., Ranjan, D., Kumar, N., Raza, M. Q., and Raj, R., 2020, “Simultaneous Audio-Visual-Thermal Characterization of Transition Boiling Regime,” Experimental Thermal and Fluid Science, 118,pp. 110162, https://doi.org/10.1016/j.expthermflusci.2020.110162.
• Sinha, K. N. R., Ranjan, D., Raza, M. Q., Kumar, N., Kaner, S., Thakur, A., and Raj, R., 2019, “In-situacoustic detection of critical heat flux for controlling thermal runaway in boiling systems,” International Journal of Heat and Mass Transfer, 138, pp. 135-149, https://doi.org/10.1016/j.ijheatmasstransfer.2019.04.029.
• Kumar, V., Sinha, K. N. R., and Raj, R., 2020, “Leidenfrost Phenomenon during Quenching in Aqueous Solutions: Effect of Evaporation-Induced Concentration Gradients,” Soft Matter, 16, pp. 6145-6154, https://doi.org/10.1039/D0SM00622J.
• Kumar, N., Sinha, K. N. R., Raza, M. Q., Verma, A., Seth, D., Jasvanth, V. S., and Raj, R., 2020, “Design, Fabrication, and Performance Evaluation of a Novel Orientation Independent and Wickless Heat Spreader,” International Journal of Heat and Mass Transfer, 153, pp. 119572, https://doi.org/10.1016/j.ijheatmasstransfer.2020.119572.
• Kumar, N., Raza, M. Q., Sinha, K. N. R., Seth, D., Raj, R., 2020, “Amphiphilic additives to enhance pool boiling heat transfer in confined spaces”, Journal of Enhanced Heat Transfer, 27 (6), 545-560, https://doi.org/10.1615/JEnhHeatTransf.2020034432.

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