From Maciej.Lisicki at fuw.edu.pl Tue Nov 4 08:43:33 2025 From: Maciej.Lisicki at fuw.edu.pl (Maciej Lisicki) Date: Tue, 4 Nov 2025 08:43:33 +0100 Subject: [Soft-matter] Soft Matter & Complex Systems Seminar on 7 Nov 2025 Message-ID: <4784EEA4-AC1F-42EB-A54B-00ACC4FBC59D@fuw.edu.pl> Dear Soft Matter & Complex Systems Colleagues and Friends, On Friday 7 November 2025 at 9:30 AM at the UW Faculty of Physics (Pasteura 5, Warsaw; room 1.40) we are hosting a seminar, during which Tomasz Szawe??o (IFT UW) will give a talk Diffusive transport in network models of dissolution in porous media Abstract Dissolution in porous media emerges from the interplay of fluid flow, reactant transport, chemical reactions, and evolving structure. Reactant transport combines advection and diffusion: advection promotes channeling instabilities, whereas diffusion stabilizes fronts. Pore network models provide an efficient framework to simulate dissolution, but often assume advection-dominated axial transport in pores?an assumption frequently violated in natural and industrial systems such as groundwater flows or catalytic reactors. In this seminar I first motivate the need to include axial diffusion in pore network models and derive the classical Graetz solution for advection?reaction in a cylindrical pore with reactive walls. I next show how retaining axial diffusion modifies the solution structure, inducing additional dependence on Damk?hler and P?clet numbers. Building on this, I present a solution to the 1D advection?diffusion?reaction problem for pores in the network that incorporates axial diffusion. Finally, I map dissolution outcomes on Damk?hler?P?clet phase diagrams, highlighting transitions in morphology and comparing them with laboratory benchmarks. We warmly welcome everyone to attend the talk and the Soft Matter Coffee Break after the seminar, held in room 2.63 (2nd floor). Maria Ekiel-Je?ewska Maciej Lisicki Piotr Szymczak Panagiotis Theodorakis -------------- next part -------------- An HTML attachment was scrubbed... URL: From Maciej.Lisicki at fuw.edu.pl Thu Nov 13 16:01:29 2025 From: Maciej.Lisicki at fuw.edu.pl (Maciej Lisicki) Date: Thu, 13 Nov 2025 16:01:29 +0100 Subject: [Soft-matter] No Soft Matter & Complex Systems Seminar on 14 Nov 2025 Message-ID: <6EC477EB-09CC-455C-A300-E9B68AE2C8FA@fuw.edu.pl> Dear Soft Matter & Complex Systems Colleagues and Friends, Just a reminder that since on Friday 14 November 2025 the Faculty of Physics operates on Tuesday schedule, there will be no seminar on this day. The next Soft Matter & Complex Systems Seminar will be held next week, on 21 November. Maria Ekiel-Je?ewska Maciej Lisicki Piotr Szymczak Panagiotis Theodorakis -------------- next part -------------- An HTML attachment was scrubbed... URL: From Piotr.Szymczak at fuw.edu.pl Thu Nov 20 17:49:58 2025 From: Piotr.Szymczak at fuw.edu.pl (Piotr Szymczak) Date: Thu, 20 Nov 2025 17:49:58 +0100 Subject: [Soft-matter] No Soft Matter & Complex Systems Seminar on 21 November 2025 Message-ID: Dear Colleagues, There will be no seminar on Friday 21 November. The next seminar will take place on 28 November 2025, with more details in the next email. Maria Ekiel-Je?ewska Maciej Lisicki Piotr Szymczak Panagiotis Theodorakis From Maciej.Lisicki at fuw.edu.pl Tue Nov 25 23:48:19 2025 From: Maciej.Lisicki at fuw.edu.pl (Maciej Lisicki) Date: Tue, 25 Nov 2025 16:48:19 -0600 Subject: [Soft-matter] Soft Matter & Complex Systems Seminar on 28 Nov 2025 Message-ID: Dear Soft Matter & Complex Systems Colleagues and Friends, On Friday 7 November 2025 at 9:30 AM at the UW Faculty of Physics (Pasteura 5, Warsaw; room 1.40) we are hosting a seminar, during which Micha? Klamka (MEiL PW) will give a talk composed of two parts: I. Hydrodynamic Levitation of Liquid Droplets on Rotating Surfaces: Experimental and CFD Analysis of Boundary Layer Interactions II. Shaking Things Up: A Dynamic Oscillation Framework For Contact Angle Hysteresis Measurement with details below: 1. Title: Hydrodynamic Levitation of Liquid Droplets on Rotating Surfaces: Experimental and CFD Analysis of Boundary Layer Interactions Abstract: The interaction of liquid droplets with solid surfaces is a phenomenon of fundamental importance across numerous industrial processes, including spray coating, spray cooling, and cleaning applications. While thermal effects, such as the well-documented Leidenfrost effect, can induce droplet levitation via a vapor cushion, analogous non-wettable behavior can be achieved at ambient temperatures through hydrodynamic means. A moving surface submerged in a fluid generates a boundary layer capable of preventing direct contact between an impacting droplet and the surface itself. This hydrodynamic levitation has been observed in both low and high-velocity flow regimes. This investigation presents a comprehensive experimental and computational fluid dynamics (CFD) analysis of the interaction between a liquid droplet and the boundary layer generated by a vertically rotating flat disk. The primary experimental objective was to determine the feasibility of achieving stable droplet levitation within both laminar and turbulent boundary layers. Furthermore, the study aimed to define the operational limits of this levitation, specifically by identifying the critical impact velocity beyond which a free-falling droplet penetrates the boundary layer and makes contact with the disk surface. The computational portion of this work focuses on elucidating the complex flow field surrounding a levitating droplet. We analyze the mutual interaction between the primary rotating disk flow and the stationary droplet, quantifying the modifications to the base flow caused by the droplet's presence and the resultant aerodynamic forces. A key aspect of this analysis is explaining the origin of observed droplet shape oscillations during levitation by examining flow instabilities and their subsequent effect on the pressure distribution across the droplet's surface. This dual approach provides a detailed understanding of the underlying physics governing hydrodynamic droplet levitation. Acknowledgments: This research was carried out with the support of the Interdisciplinary Centre for Mathematical and Computational Modelling University of Warsaw (ICM UW) under computational allocation no G100-2222. Research was funded by the Warsaw University of Technology within the Excellence Initiative: Research University (IDUB) programme. ====================== 2. Title: Shaking Things Up: A Dynamic Oscillation Framework For Contact Angle Hysteresis Measurement Abstract: This work presents a dynamic method for determining contact angle hysteresis (CAH) by placing droplets on a harmonically oscillating substrate, providing new kinetic insights into surface wettability. We designed a custom experimental setup featuring a lightweight, 3D-printed motion carriage actuated by a high-performance linear motor capable of sinusoidal oscillations with accelerations up to 9g, and equipped with a high-speed optical system for millisecond-scale imaging and analysis. Silicon wafers were used as substrates with Glaco superhydrophobic surface treatment, and deionised water was chosen as the working fluid due to its well-characterized and reproducible physicochemical properties, ensuring comparability and minimizing variability. The integrated imaging and analysis approach, including precise droplet deposition and a robust MATLAB processing pipeline, enabled accurate measurement of contact angle dynamics and improved uncertainty quantification. Results show this oscillation-based method effectively probes the thresholds required for depinning, advances the study of dynamic droplet mobility, and facilitates detection of local surface heterogeneities, outperforming conventional static and quasi-static CAH measurement techniques. We warmly welcome everyone to attend the talk and the Soft Matter Coffee Break after the seminar, held in room 2.63 (2nd floor). Maria Ekiel-Je?ewska Maciej Lisicki Piotr Szymczak Panagiotis Theodorakis -------------- next part -------------- An HTML attachment was scrubbed... URL: From Maciej.Lisicki at fuw.edu.pl Wed Nov 26 13:30:58 2025 From: Maciej.Lisicki at fuw.edu.pl (Maciej Lisicki) Date: Wed, 26 Nov 2025 06:30:58 -0600 Subject: [Soft-matter] Soft Matter & Complex Systems Seminar on 28 Nov 2025 In-Reply-To: References: Message-ID: <5B5CE99A-6DA4-44DA-8682-234A767F3DF7@fuw.edu.pl> Dear all, Apologies for a typographical error in the email below ? the seminar of Micha? Klamka will be held this Friday, on 28 November. Best wishes, ML -- Maciej Lisicki Insitute of Theoretical Physics | Faculty of Physics University of Warsaw http://softmatter.fuw.edu.pl > On 25 Nov 2025, at 16:48, Maciej Lisicki wrote: > ? > Dear Soft Matter & Complex Systems Colleagues and Friends, > > On Friday 7 November 2025 at 9:30 AM at the UW Faculty of Physics (Pasteura 5, Warsaw; room 1.40) we are hosting a seminar, during which > > Micha? Klamka (MEiL PW) > > will give a talk composed of two parts: > > I. Hydrodynamic Levitation of Liquid Droplets on Rotating Surfaces: Experimental and CFD Analysis of Boundary Layer Interactions > II. Shaking Things Up: A Dynamic Oscillation Framework For Contact Angle Hysteresis Measurement > > with details below: > > 1. Title: Hydrodynamic Levitation of Liquid Droplets on Rotating Surfaces: Experimental and CFD Analysis of Boundary Layer Interactions > > Abstract: The interaction of liquid droplets with solid surfaces is a phenomenon of fundamental importance across numerous industrial processes, including spray coating, spray cooling, and cleaning applications. While thermal effects, such as the well-documented Leidenfrost effect, can induce droplet levitation via a vapor cushion, analogous non-wettable behavior can be achieved at ambient temperatures through hydrodynamic means. A moving surface submerged in a fluid generates a boundary layer capable of preventing direct contact between an impacting droplet and the surface itself. This hydrodynamic levitation has been observed in both low and high-velocity flow regimes. > This investigation presents a comprehensive experimental and computational fluid dynamics (CFD) analysis of the interaction between a liquid droplet and the boundary layer generated by a vertically rotating flat disk. The primary experimental objective was to determine the feasibility of achieving stable droplet levitation within both laminar and turbulent boundary layers. Furthermore, the study aimed to define the operational limits of this levitation, specifically by identifying the critical impact velocity beyond which a free-falling droplet penetrates the boundary layer and makes contact with the disk surface. > The computational portion of this work focuses on elucidating the complex flow field surrounding a levitating droplet. We analyze the mutual interaction between the primary rotating disk flow and the stationary droplet, quantifying the modifications to the base flow caused by the droplet's presence and the resultant aerodynamic forces. A key aspect of this analysis is explaining the origin of observed droplet shape oscillations during levitation by examining flow instabilities and their subsequent effect on the pressure distribution across the droplet's surface. This dual approach provides a detailed understanding of the underlying physics governing hydrodynamic droplet levitation. > > Acknowledgments: This research was carried out with the support of the Interdisciplinary Centre for Mathematical and Computational Modelling University of Warsaw (ICM UW) under computational allocation no G100-2222. Research was funded by the Warsaw University of Technology within the Excellence Initiative: Research University (IDUB) programme. > > ====================== > > 2. Title: Shaking Things Up: A Dynamic Oscillation Framework For Contact Angle Hysteresis Measurement > > Abstract: This work presents a dynamic method for determining contact angle hysteresis (CAH) by placing droplets on a harmonically oscillating substrate, providing new kinetic insights into surface wettability. We designed a custom experimental setup featuring a lightweight, 3D-printed motion carriage actuated by a high-performance linear motor capable of sinusoidal oscillations with accelerations up to 9g, and equipped with a high-speed optical system for millisecond-scale imaging and analysis. Silicon wafers were used as substrates with Glaco superhydrophobic surface treatment, and deionised water was chosen as the working fluid due to its well-characterized and reproducible physicochemical properties, ensuring comparability and minimizing variability. The integrated imaging and analysis approach, including precise droplet deposition and a robust MATLAB processing pipeline, enabled accurate measurement of contact angle dynamics and improved uncertainty quantification. Results show this oscillation-based method effectively probes the thresholds required for depinning, advances the study of dynamic droplet mobility, and facilitates detection of local surface heterogeneities, outperforming conventional static and quasi-static CAH measurement techniques. > > We warmly welcome everyone to attend the talk and the Soft Matter Coffee Break after the seminar, held in room 2.63 (2nd floor). > > Maria Ekiel-Je?ewska > Maciej Lisicki > Piotr Szymczak > Panagiotis Theodorakis > > _______________________________________________ > Soft-matter mailing list > Soft-matter at fuw.edu.pl > http://tempulin.fuw.edu.pl/mailman/listinfo/soft-matter -------------- next part -------------- An HTML attachment was scrubbed... URL: