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Kinetics of Precipitation Processes at Non-Zero Input Fluxes of Segregating Particles
Jürn W P Schmelzer1,2, Timur V Tropin3, Alexander S Abyzov4
1Institut für Physik der Universität Rostock, Albert-Einstein-Strasse 23-25, 18059 Rostock, Germany.
Entropy (Basel, Switzerland)
|February 25, 2023
Summary
Continuous particle addition in open systems impacts cluster formation and growth. This study develops a new theory for Ostwald ripening, improving upon classical models for systems with changing conditions.
Area of Science:
- Materials Science
- Physical Chemistry
- Chemical Engineering
Background:
- Segregation processes in open systems involve the formation and growth of new phases.
- Classical Lifshitz, Slezov and Wagner (LSW) theory describes Ostwald ripening but has limitations in open systems.
- Understanding cluster dynamics is crucial for controlling material properties.
Purpose of the Study:
- To investigate the effect of continuous input flux on cluster formation and growth kinetics in open systems.
- To develop a theoretical framework for Ostwald ripening in open systems that accounts for time-varying boundary conditions.
- To provide a method for theoretically testing conditions to achieve desired cluster size distributions.
Main Methods:
- Numerical computations to simulate cluster formation and growth.
- Analytical treatment to develop a theory for coarsening kinetics.
- Extension of classical Ostwald ripening theory to open systems.
Main Results:
- Input flux significantly influences the number of supercritical clusters, growth kinetics, and late-stage coarsening.
- A new treatment of coarsening kinetics is developed, describing cluster number and average size evolution.
- The developed approach extends beyond classical LSW theory for open systems.
Conclusions:
- The study provides a generalized tool for describing Ostwald ripening in open systems and systems with time-varying boundary conditions.
- This theoretical framework allows for the optimization of conditions to achieve specific cluster size distributions for applications.
- The findings offer a deeper understanding of phase segregation dynamics in non-equilibrium systems.
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