Presentation Information
[O12-P87]Influence of Ambient Fluid Viscosity and Density on the Deposition Range of Particles Ejected from a Nozzle
*Daiki Chiba1, Riich Ito1, Ritsuto Tamura1 (1. Hyogo Prefectural Nagata High School)
Keywords:
hydrothermal vent,Enceladus,liquid,viscosity,deposition
1. Research Background
Hydrothermal vents on Earth's seafloor eject hot water and fine particles. Considered highly likely to be the origin of life, they provide a suitable environment for its emergence. Identical vent structures may exist beneath the subsurface ocean of Saturn's moon, Enceladus, making them prime candidates for extraterrestrial life exploration. We initiated this research because the surrounding environment—particularly topography—greatly influences life.
2. Research Objective and Significance
By varying the surrounding liquid's conditions (specifically viscosity and density), we investigate changes in the deposition range of particles ejected from vents. Deepening our understanding of vent topographical formation in environments beyond Earth's seafloor will expand geological knowledge and advance discussions on the potential for extraterrestrial life near hydrothermal vents.
3. Research Methods
We constructed an experimental vent model (Figures 1A, 1B).
Experimental Procedures:
Fill the container, catheter, and syringe with Liquid A, adjusted for viscosity (using PVA aqueous solution) and density (using NaCl aqueous solution). Load the syringe with a fixed amount of glass beads, dyed black with lacquer spray for later analysis. Manually extrude 10 ml of the Liquid A and bead mixture in 1 second. Photograph the container's bottom using an overhead CMOS camera to confirm deposition. (This process was repeated 20 times for each viscosity and density condition.)
Analytical Procedures (Figure 2): Binarize the images so only the glass beads appear white. Use a custom program to calculate the glass beads' area ratio within concentric rings based on the distance from the central tube. Plot the distance ($x$) against the bead area ratio ($f(x)$). Since $f(x)$ can be approximated by the exponential function $Ae^{-Bx}$, the "deposition range" is defined as the reciprocal of $B$.
4. Results and Discussion
Viscosity: A strong exponential correlation exists with the deposition range (Figure 3). This is supported by a high coefficient of determination ($R^2 = 0.9912$). As viscosity increases, ejected beads are more easily pulled upward with the rising fluid, expanding the deposition range (Figure 4).
Density: The deposition range increased up to a density of 1.1, but decreased thereafter (Figure 5). This was likely caused by a coagulation-like reaction between the nitrocellulose in the lacquer spray and the NaCl solution (refer to DLVO theory for reaction details).
5. Conclusion and Future Prospects
The deposition range shows a strong exponential correlation with viscosity. Future studies should accurately evaluate density effects using non-electrolyte solutions to prevent coagulation, and conduct experiments with varying particle sizes to verify size dependence.
Acknowledgments
We sincerely thank our supervisors, Mr. Katsuno and Mr. Hiraoka, and the Educational Planning and Promotion Department teachers at Hyogo Prefectural Nagata High School for their extensive guidance.
References
Z. He, X. Han (2020) "Transport and deposition patterns of particles laden by rising submarine hydrothermal plumes", Geophysical Research Letters, 47, e2020GL089935 Kuraray Co., Ltd. (2025) "Physical Properties of PVOH Resin", Technical Data (Accessed Dec 11, 2025) A. Kuroiwa (1952) "Viscosity of Dilute Aqueous Solutions of Polyvinyl Alcohol", Kobunshi Kagaku, 9, 253-260 H. Ozbek, J.A. Fair, S.L. Phillips (1977) "Viscosity of Aqueous Sodium Chloride Solutions From 0-150℃", Lawrence Berkeley National Laboratory AdvancedThermo "Density of sodium chloride, NaCl(aq)" https://advancedthermo.com/electrolytes/density_NaCl.html (Accessed Feb 4, 2026)
Hydrothermal vents on Earth's seafloor eject hot water and fine particles. Considered highly likely to be the origin of life, they provide a suitable environment for its emergence. Identical vent structures may exist beneath the subsurface ocean of Saturn's moon, Enceladus, making them prime candidates for extraterrestrial life exploration. We initiated this research because the surrounding environment—particularly topography—greatly influences life.
2. Research Objective and Significance
By varying the surrounding liquid's conditions (specifically viscosity and density), we investigate changes in the deposition range of particles ejected from vents. Deepening our understanding of vent topographical formation in environments beyond Earth's seafloor will expand geological knowledge and advance discussions on the potential for extraterrestrial life near hydrothermal vents.
3. Research Methods
We constructed an experimental vent model (Figures 1A, 1B).
Experimental Procedures:
Fill the container, catheter, and syringe with Liquid A, adjusted for viscosity (using PVA aqueous solution) and density (using NaCl aqueous solution). Load the syringe with a fixed amount of glass beads, dyed black with lacquer spray for later analysis. Manually extrude 10 ml of the Liquid A and bead mixture in 1 second. Photograph the container's bottom using an overhead CMOS camera to confirm deposition. (This process was repeated 20 times for each viscosity and density condition.)
Analytical Procedures (Figure 2): Binarize the images so only the glass beads appear white. Use a custom program to calculate the glass beads' area ratio within concentric rings based on the distance from the central tube. Plot the distance ($x$) against the bead area ratio ($f(x)$). Since $f(x)$ can be approximated by the exponential function $Ae^{-Bx}$, the "deposition range" is defined as the reciprocal of $B$.
4. Results and Discussion
Viscosity: A strong exponential correlation exists with the deposition range (Figure 3). This is supported by a high coefficient of determination ($R^2 = 0.9912$). As viscosity increases, ejected beads are more easily pulled upward with the rising fluid, expanding the deposition range (Figure 4).
Density: The deposition range increased up to a density of 1.1, but decreased thereafter (Figure 5). This was likely caused by a coagulation-like reaction between the nitrocellulose in the lacquer spray and the NaCl solution (refer to DLVO theory for reaction details).
5. Conclusion and Future Prospects
The deposition range shows a strong exponential correlation with viscosity. Future studies should accurately evaluate density effects using non-electrolyte solutions to prevent coagulation, and conduct experiments with varying particle sizes to verify size dependence.
Acknowledgments
We sincerely thank our supervisors, Mr. Katsuno and Mr. Hiraoka, and the Educational Planning and Promotion Department teachers at Hyogo Prefectural Nagata High School for their extensive guidance.
References
Z. He, X. Han (2020) "Transport and deposition patterns of particles laden by rising submarine hydrothermal plumes", Geophysical Research Letters, 47, e2020GL089935 Kuraray Co., Ltd. (2025) "Physical Properties of PVOH Resin", Technical Data (Accessed Dec 11, 2025) A. Kuroiwa (1952) "Viscosity of Dilute Aqueous Solutions of Polyvinyl Alcohol", Kobunshi Kagaku, 9, 253-260 H. Ozbek, J.A. Fair, S.L. Phillips (1977) "Viscosity of Aqueous Sodium Chloride Solutions From 0-150℃", Lawrence Berkeley National Laboratory AdvancedThermo "Density of sodium chloride, NaCl(aq)" https://advancedthermo.com/electrolytes/density_NaCl.html (Accessed Feb 4, 2026)