Microbubble dynamics and heat transfer in boiling droplets
Navid Saneie, Varun Kulkarni, Bruce Treska, Kamel Fezzaa, Neelesh Patankar, Sushant Anand*
Dissipating large heat fluxes from a surface is critically important in numerous industrial and natural applications. Boiling based spray cooling and surface texturing are two of the most promising methods being investigated to address this problem. Although our understanding on these topics has significantly improved over past decades, critical gaps remain in the knowledgebase stymieing the realization of their full potential. As an example, while bubble growth in pool boiling have been investigated in detail, comparatively little is known about how the bubbles evolve inside boiling drops. In the present work, we have investigated for the first time, the microbubble dynamics inside water droplets boiling on superhydrophilic textured substrates using high-speed X-ray phase contrast imaging (XRPCI). Our observations show that the transient bubble density variation follows similar characteristics irrespective of the texture spacing at a given surface temperature. For an example microstructure, we found that the number of discrete bubbles on the surface decreases as temperature is increased although their growth rate increases. We observe that bubble growth is highly non-uniform during the lifetime of a drop on the surface. Initially, bubbles grow under diffusion-limited regime, but at later times they grow as ~t1.45 due to combined effects of coalescence and evaporation. In some conditions, we found that bubbles shrink dramatically after the initial growth spurt presumably due to severe quenching of the surface, and migration of bubbles on the surface. Using the bubble sizes, for the first time we analyzed the heat flux removed by a single bubble and also by all the bubbles at a given time. We find that the highest dissipation through latent-heat component (~600 W/cm2) occurs just in the beginning and thereafter it decreases. We expect that our findings and the analysis would guide further work on the topic and will aid in the overarching goal of engineering surfaces that are more efficient in boiling heat transfer.
International Journal of Heat and Mass Transfer
https://doi.org/10.1016/j.ijheatmasstransfer.2021.121413
Bubble growth
Spray cooling
Textured surfaces
10.1016/j.ijheatmasstransfer.2021.121413
Dive into the research topics of 'Microbubble dynamics and heat transfer in boiling droplets'. Together they form a unique fingerprint.
Heat Transfer Chemical Compounds 100%
Bubble Chemical Compounds 97%
Boiling liquids Engineering & Materials Science 94%
boiling Physics & Astronomy 91%
Boiling Chemical Compounds 91%
heat transfer Physics & Astronomy 72%
Heat transfer Engineering & Materials Science 61%
Saneie, N., Kulkarni, V., Treska, B., Fezzaa, K., Patankar, N., & Anand, S. (2021). Microbubble dynamics and heat transfer in boiling droplets. International Journal of Heat and Mass Transfer, 176, [121413]. https://doi.org/10.1016/j.ijheatmasstransfer.2021.121413
Saneie, Navid ; Kulkarni, Varun ; Treska, Bruce ; Fezzaa, Kamel ; Patankar, Neelesh ; Anand, Sushant. / Microbubble dynamics and heat transfer in boiling droplets. In: International Journal of Heat and Mass Transfer. 2021 ; Vol. 176.
@article{bfa22de0859e439584ee8f88c2d2cb5d,
title = "Microbubble dynamics and heat transfer in boiling droplets",
abstract = "Dissipating large heat fluxes from a surface is critically important in numerous industrial and natural applications. Boiling based spray cooling and surface texturing are two of the most promising methods being investigated to address this problem. Although our understanding on these topics has significantly improved over past decades, critical gaps remain in the knowledgebase stymieing the realization of their full potential. As an example, while bubble growth in pool boiling have been investigated in detail, comparatively little is known about how the bubbles evolve inside boiling drops. In the present work, we have investigated for the first time, the microbubble dynamics inside water droplets boiling on superhydrophilic textured substrates using high-speed X-ray phase contrast imaging (XRPCI). Our observations show that the transient bubble density variation follows similar characteristics irrespective of the texture spacing at a given surface temperature. For an example microstructure, we found that the number of discrete bubbles on the surface decreases as temperature is increased although their growth rate increases. We observe that bubble growth is highly non-uniform during the lifetime of a drop on the surface. Initially, bubbles grow under diffusion-limited regime, but at later times they grow as ~t1.45 due to combined effects of coalescence and evaporation. In some conditions, we found that bubbles shrink dramatically after the initial growth spurt presumably due to severe quenching of the surface, and migration of bubbles on the surface. Using the bubble sizes, for the first time we analyzed the heat flux removed by a single bubble and also by all the bubbles at a given time. We find that the highest dissipation through latent-heat component (~600 W/cm2) occurs just in the beginning and thereafter it decreases. We expect that our findings and the analysis would guide further work on the topic and will aid in the overarching goal of engineering surfaces that are more efficient in boiling heat transfer.",
keywords = "Boiling, Bubble growth, Heat transfer, Spray cooling, Textured surfaces",
author = "Navid Saneie and Varun Kulkarni and Bruce Treska and Kamel Fezzaa and Neelesh Patankar and Sushant Anand",
note = "Funding Information: The fabrication of silicon surfaces was performed at Pritzker Nanofabrication Facility (University of Chicago). The SEM of samples was obtained at the Electron Microscopy Service (Research Resources Center, UIC). SA thanks the financial support of UIC College of Engineering. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Funding Information: The fabrication of silicon surfaces was performed at Pritzker Nanofabrication Facility (University of Chicago). The SEM of samples was obtained at the Electron Microscopy Service (Research Resources Center, UIC). SA thanks the financial support of UIC College of Engineering. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Publisher Copyright: {\textcopyright} 2021 Elsevier Ltd",
doi = "10.1016/j.ijheatmasstransfer.2021.121413",
journal = "International Journal of Heat and Mass Transfer",
Saneie, N, Kulkarni, V, Treska, B, Fezzaa, K, Patankar, N & Anand, S 2021, 'Microbubble dynamics and heat transfer in boiling droplets', International Journal of Heat and Mass Transfer, vol. 176, 121413. https://doi.org/10.1016/j.ijheatmasstransfer.2021.121413
Microbubble dynamics and heat transfer in boiling droplets. / Saneie, Navid; Kulkarni, Varun; Treska, Bruce; Fezzaa, Kamel; Patankar, Neelesh; Anand, Sushant.
In: International Journal of Heat and Mass Transfer, Vol. 176, 121413, 09.2021.
T1 - Microbubble dynamics and heat transfer in boiling droplets
AU - Saneie, Navid
AU - Kulkarni, Varun
AU - Treska, Bruce
AU - Fezzaa, Kamel
AU - Patankar, Neelesh
AU - Anand, Sushant
N1 - Funding Information: The fabrication of silicon surfaces was performed at Pritzker Nanofabrication Facility (University of Chicago). The SEM of samples was obtained at the Electron Microscopy Service (Research Resources Center, UIC). SA thanks the financial support of UIC College of Engineering. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Funding Information: The fabrication of silicon surfaces was performed at Pritzker Nanofabrication Facility (University of Chicago). The SEM of samples was obtained at the Electron Microscopy Service (Research Resources Center, UIC). SA thanks the financial support of UIC College of Engineering. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Publisher Copyright: © 2021 Elsevier Ltd
N2 - Dissipating large heat fluxes from a surface is critically important in numerous industrial and natural applications. Boiling based spray cooling and surface texturing are two of the most promising methods being investigated to address this problem. Although our understanding on these topics has significantly improved over past decades, critical gaps remain in the knowledgebase stymieing the realization of their full potential. As an example, while bubble growth in pool boiling have been investigated in detail, comparatively little is known about how the bubbles evolve inside boiling drops. In the present work, we have investigated for the first time, the microbubble dynamics inside water droplets boiling on superhydrophilic textured substrates using high-speed X-ray phase contrast imaging (XRPCI). Our observations show that the transient bubble density variation follows similar characteristics irrespective of the texture spacing at a given surface temperature. For an example microstructure, we found that the number of discrete bubbles on the surface decreases as temperature is increased although their growth rate increases. We observe that bubble growth is highly non-uniform during the lifetime of a drop on the surface. Initially, bubbles grow under diffusion-limited regime, but at later times they grow as ~t1.45 due to combined effects of coalescence and evaporation. In some conditions, we found that bubbles shrink dramatically after the initial growth spurt presumably due to severe quenching of the surface, and migration of bubbles on the surface. Using the bubble sizes, for the first time we analyzed the heat flux removed by a single bubble and also by all the bubbles at a given time. We find that the highest dissipation through latent-heat component (~600 W/cm2) occurs just in the beginning and thereafter it decreases. We expect that our findings and the analysis would guide further work on the topic and will aid in the overarching goal of engineering surfaces that are more efficient in boiling heat transfer.
AB - Dissipating large heat fluxes from a surface is critically important in numerous industrial and natural applications. Boiling based spray cooling and surface texturing are two of the most promising methods being investigated to address this problem. Although our understanding on these topics has significantly improved over past decades, critical gaps remain in the knowledgebase stymieing the realization of their full potential. As an example, while bubble growth in pool boiling have been investigated in detail, comparatively little is known about how the bubbles evolve inside boiling drops. In the present work, we have investigated for the first time, the microbubble dynamics inside water droplets boiling on superhydrophilic textured substrates using high-speed X-ray phase contrast imaging (XRPCI). Our observations show that the transient bubble density variation follows similar characteristics irrespective of the texture spacing at a given surface temperature. For an example microstructure, we found that the number of discrete bubbles on the surface decreases as temperature is increased although their growth rate increases. We observe that bubble growth is highly non-uniform during the lifetime of a drop on the surface. Initially, bubbles grow under diffusion-limited regime, but at later times they grow as ~t1.45 due to combined effects of coalescence and evaporation. In some conditions, we found that bubbles shrink dramatically after the initial growth spurt presumably due to severe quenching of the surface, and migration of bubbles on the surface. Using the bubble sizes, for the first time we analyzed the heat flux removed by a single bubble and also by all the bubbles at a given time. We find that the highest dissipation through latent-heat component (~600 W/cm2) occurs just in the beginning and thereafter it decreases. We expect that our findings and the analysis would guide further work on the topic and will aid in the overarching goal of engineering surfaces that are more efficient in boiling heat transfer.
KW - Boiling
KW - Bubble growth
KW - Heat transfer
KW - Spray cooling
KW - Textured surfaces
U2 - 10.1016/j.ijheatmasstransfer.2021.121413
DO - 10.1016/j.ijheatmasstransfer.2021.121413
JO - International Journal of Heat and Mass Transfer
JF - International Journal of Heat and Mass Transfer
Saneie N, Kulkarni V, Treska B, Fezzaa K, Patankar N, Anand S. Microbubble dynamics and heat transfer in boiling droplets. International Journal of Heat and Mass Transfer. 2021 Sep;176. 121413. https://doi.org/10.1016/j.ijheatmasstransfer.2021.121413