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Dynamic Behaviors of Condensing Clusters Based on Rayleigh Scattering Experiment
Zhong Lan1, Di Wang1, Kejian Cao1,2
1State Key Laboratory of Fine Chemicals, Liaoning Key Laboratory of Clean Utilization of Chemical Resources, Institute of Chemical Engineering, Dalian University of Technology, Dalian, 116024, China.
Scientific Reports
|April 22, 2017
Summary
This study introduces an optical platform to investigate dynamic clusters during condensation. Results show clusters form near surfaces and vanish quickly, with number density, not radius, dominating the process.
Area of Science:
- Physics
- Thermodynamics
- Fluid Dynamics
Background:
- Condensation is a crucial physical process in nature and thermal systems.
- Clusters act as key intermediates between vapor and condensate phases.
- Traditional methods lack resolution for studying early condensation stages.
Purpose of the Study:
- To develop and utilize a novel optical platform for observing dynamic cluster formation during condensation.
- To investigate the spatial distribution and life cycle of clusters near a condensation surface.
Main Methods:
- Utilized an optical platform based on Rayleigh scattering.
- Conducted experiments to analyze cluster spatial distribution.
- Measured cluster behavior in relation to condensation surface proximity and subcooling degree.
Main Results:
- Clusters predominantly form within 200 micrometers of the condensation surface.
- Observed clusters have a short life cycle, lasting milliseconds.
- Scattering intensity is primarily influenced by cluster number density, not radius, with increasing subcooling.
Conclusions:
- The developed optical platform enables detailed study of dynamic condensation clusters.
- Cluster formation is localized near the condensation surface.
- Cluster number density is the dominant factor affecting condensation dynamics, overriding cluster radius effects.
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