New insights into physics of explosive water boiling derived from molecular dynamics simulations
Abstract
In this paper the dynamics of explosive boiling of a 72 angstrom thick water film on the hot copper substrate with the plain surface is analysed. The analyses are based on the results of molecular dynamics (MD) simulations of the transient in which the thermostat temperature within the solid substrate is increased from 298 to 800K. The obtained results show that explosive boiling comprises several phases. The first phase involves rapid thermoacoustic pressure build-up in the near wall region due to intensive water heating and its volumetric expansion. The generated compression wave propagates through the liquid film reaching the peak value higher than critical water pressure. Due to reflection at the free film surface the original compression wave turns into an expansion wave. This event leads to a rapid pressure decrease and occurrence of tension stress. The second phase starts when the pressure enters the negative domain. This phase is accompanied with nucleation of vapour embryos an...d their subsequent growth in the superheated water layer in the near wall region. As the intensity of vapour phase generation is moderate, the liquid film in this phase is still exposed to tension. The stress recovery starts in the third phase when the water temperature in the near wall layer attains the spinodal value. This leads to a massive vaporization, nanobubble coalescence and thermal explosion, which causes spallation of the liquid film and lift-off of the liquid slug. The last phase is characterized by suppression of heat transfer by the expanding vapour layer. As a consequence, after reaching the maximum, the pressure decreases. This paper gives quantitative description and detailed insight into the mechanisms associated with each of the aforementioned phases.
Keywords:
Vapour generation / Thermal- and hydrodynamics / Molecular dynamics / Liquid slug lift-off / Explosive boilingSource:
International Journal of Heat and Mass Transfer, 2021, 172, 121141-Publisher:
- Pergamon-Elsevier Science Ltd, Oxford
Funding / projects:
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200105 (University of Belgrade, Faculty of Mechanical Engineering) (RS-MESTD-inst-2020-200105)
- Ministry of Science, Technological Development and Innovation of the Republic of Serbia, institutional funding - 200213 (Innovation Center of the Faculty of Mechanical Engineering) (RS-MESTD-inst-2020-200213)
DOI: 10.1016/j.ijheatmasstransfer.2021.121141
ISSN: 0017-9310
WoS: 000641142400020
Scopus: 2-s2.0-85102346168
Collections
Institution/Community
Inovacioni centarTY - JOUR AU - Ilić, Milica AU - Stevanović, Vladimir AU - Milivojević, Sanja AU - Petrović, Milan M. PY - 2021 UR - https://machinery.mas.bg.ac.rs/handle/123456789/3609 AB - In this paper the dynamics of explosive boiling of a 72 angstrom thick water film on the hot copper substrate with the plain surface is analysed. The analyses are based on the results of molecular dynamics (MD) simulations of the transient in which the thermostat temperature within the solid substrate is increased from 298 to 800K. The obtained results show that explosive boiling comprises several phases. The first phase involves rapid thermoacoustic pressure build-up in the near wall region due to intensive water heating and its volumetric expansion. The generated compression wave propagates through the liquid film reaching the peak value higher than critical water pressure. Due to reflection at the free film surface the original compression wave turns into an expansion wave. This event leads to a rapid pressure decrease and occurrence of tension stress. The second phase starts when the pressure enters the negative domain. This phase is accompanied with nucleation of vapour embryos and their subsequent growth in the superheated water layer in the near wall region. As the intensity of vapour phase generation is moderate, the liquid film in this phase is still exposed to tension. The stress recovery starts in the third phase when the water temperature in the near wall layer attains the spinodal value. This leads to a massive vaporization, nanobubble coalescence and thermal explosion, which causes spallation of the liquid film and lift-off of the liquid slug. The last phase is characterized by suppression of heat transfer by the expanding vapour layer. As a consequence, after reaching the maximum, the pressure decreases. This paper gives quantitative description and detailed insight into the mechanisms associated with each of the aforementioned phases. PB - Pergamon-Elsevier Science Ltd, Oxford T2 - International Journal of Heat and Mass Transfer T1 - New insights into physics of explosive water boiling derived from molecular dynamics simulations SP - 121141 VL - 172 DO - 10.1016/j.ijheatmasstransfer.2021.121141 ER -
@article{ author = "Ilić, Milica and Stevanović, Vladimir and Milivojević, Sanja and Petrović, Milan M.", year = "2021", abstract = "In this paper the dynamics of explosive boiling of a 72 angstrom thick water film on the hot copper substrate with the plain surface is analysed. The analyses are based on the results of molecular dynamics (MD) simulations of the transient in which the thermostat temperature within the solid substrate is increased from 298 to 800K. The obtained results show that explosive boiling comprises several phases. The first phase involves rapid thermoacoustic pressure build-up in the near wall region due to intensive water heating and its volumetric expansion. The generated compression wave propagates through the liquid film reaching the peak value higher than critical water pressure. Due to reflection at the free film surface the original compression wave turns into an expansion wave. This event leads to a rapid pressure decrease and occurrence of tension stress. The second phase starts when the pressure enters the negative domain. This phase is accompanied with nucleation of vapour embryos and their subsequent growth in the superheated water layer in the near wall region. As the intensity of vapour phase generation is moderate, the liquid film in this phase is still exposed to tension. The stress recovery starts in the third phase when the water temperature in the near wall layer attains the spinodal value. This leads to a massive vaporization, nanobubble coalescence and thermal explosion, which causes spallation of the liquid film and lift-off of the liquid slug. The last phase is characterized by suppression of heat transfer by the expanding vapour layer. As a consequence, after reaching the maximum, the pressure decreases. This paper gives quantitative description and detailed insight into the mechanisms associated with each of the aforementioned phases.", publisher = "Pergamon-Elsevier Science Ltd, Oxford", journal = "International Journal of Heat and Mass Transfer", title = "New insights into physics of explosive water boiling derived from molecular dynamics simulations", pages = "121141", volume = "172", doi = "10.1016/j.ijheatmasstransfer.2021.121141" }
Ilić, M., Stevanović, V., Milivojević, S.,& Petrović, M. M.. (2021). New insights into physics of explosive water boiling derived from molecular dynamics simulations. in International Journal of Heat and Mass Transfer Pergamon-Elsevier Science Ltd, Oxford., 172, 121141. https://doi.org/10.1016/j.ijheatmasstransfer.2021.121141
Ilić M, Stevanović V, Milivojević S, Petrović MM. New insights into physics of explosive water boiling derived from molecular dynamics simulations. in International Journal of Heat and Mass Transfer. 2021;172:121141. doi:10.1016/j.ijheatmasstransfer.2021.121141 .
Ilić, Milica, Stevanović, Vladimir, Milivojević, Sanja, Petrović, Milan M., "New insights into physics of explosive water boiling derived from molecular dynamics simulations" in International Journal of Heat and Mass Transfer, 172 (2021):121141, https://doi.org/10.1016/j.ijheatmasstransfer.2021.121141 . .