Gianni Cassoni
Microgravity propellant sloshing · in-orbit refuelling & servicing
The interactive model above is a coupled reduced-order simulation of spacecraft rigid-body motion and capillary propellant sloshing. Drag to orbit the view and use the thruster pads to perturb the tank across gravity levels (from Earth to capillary Bond numbers), propellants and fill ratios — part of my PhD research on in-orbit refuelling and servicing.
About
I am a PhD candidate developing models of microgravity sloshing for in-orbit refuelling and servicing. My work spans semi-analytical formulations for capillary sloshing and a coupled OpenFOAM–MBDyn framework for ullage-impact loads on spacecraft structures, backed by high-performance computing on CINECA Leonardo. I also supervise thesis students in technical work and research planning.
Thales Alenia Space & Roma Tre University
PhD Candidate. Semi-analytical capillary sloshing models and a coupled OpenFOAM–MBDyn framework for ullage-impact loads; thesis-student supervision.
Politecnico di Milano
Fellow Researcher. Rotorcraft fleet forecasting to 2050, ATTILA tiltrotor aeroelastic flutter (with Leonardo, NLR, DLR), and rotorcraft–pilot coupling data analysis.
Research highlight
Curvature-corrected sloshing spectra for microgravity. Classical slosh models assume a flat interface. In microgravity, surface tension dominates and the equilibrium meniscus is strongly curved, shifting the natural frequencies and mode shapes. The demo above evaluates a reduced-order model built from a Young–Laplace equilibrium and a modal eigen-solve, then time-steps the coupled rigid-body + slosh dynamics live in your browser. Featured update on LinkedIn.
Selected publications
- Cassoni, G., Serafini, J., Gennari, F., & Masarati, P. (2026). Coupled Fluid–Multibody Simulation of Ullage Impact Loads on Spacecraft. Preprint, under review at Multibody System Dynamics. DOI
- Cassoni, G. Curvature-corrected sloshing spectra for cylindrical tanks in microgravity. Preprint (2026)
- Cassoni, G., Cocco, A., Tamer, A., Zanoni, A., & Masarati, P. (2024). Rotorcraft stability analysis using Lyapunov characteristic exponents estimated from multibody dynamics. CEAS Aeronautical Journal, 15(3), 703–719. DOI
- Cassoni, G., Zanoni, A., Tamer, A., & Masarati, P. (2023). Stability analysis of nonlinear rotating systems using Lyapunov characteristic exponents estimated from multibody dynamics. Journal of Computational and Nonlinear Dynamics, 18(8), 081002. DOI
- Trevisi, F., Cassoni, G., Gaunaa, M., & Fagiano, L. M. (2026). Concurrent aerodynamic design of the wing and the turbines of airborne wind energy systems. Wind Energy Science, 11(1), 195–216. DOI
- De Vita, P., Cassoni, G., Morandini, M., Masarati, P., Fonte, F., Favale, M., & van’t Hoff, S. (2026). Numerical interpretation of whirl flutter in a tiltrotor wind-tunnel model using mid-fidelity aerodynamics and mechanical friction. CEAS Aeronautical Journal. DOI
- Cassoni, G., Gennari, F., Serafini, J., & Masarati, P. Curvature-Corrected Sloshing Spectrum via Diffeomorphism of the Zakharov–Craig–Sulem Formulation for Microgravity Applications. NODYCON 2026, Rome, Italy, Sep 20–23, 2026.
- Cassoni, G., Nerattini, A., Colella, A., Gennari, F., Serafini, J., & Masarati, P. On the CFD Fidelity Requirements for Assessing Classical Slosh Models in On-Orbit Servicing Regimes. ESA GNC & ICATT, Seville, Spain, Sep 28–Oct 2, 2026.
- Cassoni, G., Madonna, D. P., Colella, A., Gennari, F., Serafini, J., & Masarati, P. Reduced-Order Modeling of Propellant Sloshing via Differential Variational Inequalities for On-Orbit Refueling Docking Missions. 77th International Astronautical Congress, Antalya, Türkiye, Oct 5–9, 2026.
- Cassoni, G., Cocco, A., Tamer, A., Zanoni, A., & Masarati, P. (2023). Tiltrotor whirl-flutter stability analysis using the maximum Lyapunov characteristic exponent estimated from time series. AIDAA XXVII International Congress (2023), vol. 37, pp. 30–33. DOI
- Zanoni, A., Cassoni, G., Talamo, C., Marchesoli, D., Zilletti, M., Colombo, F., & Masarati, P. (2024). An uncertainty propagation approach to collective bounce rotorcraft–pilot couplings analysis. 80th Annual Forum, Vertical Flight Society (2024). DOI
- Cassoni, G., Zanoni, A., Tamer, A., & Masarati, P. (2022). Stability of rotorcraft ground resonance by estimating Lyapunov characteristic exponents from multibody dynamics. ASME IDETC/CIE 2022. DOI
Awards & competitive funding
100,000 CPU core-hours on Leonardo Data Centric and 10,000 GPU-hours on Leonardo Booster for high-performance studies on microgravity sloshing and reduced-order modeling.
Technical skills
Research interests
Beyond spaceflight fluid dynamics, I am drawn to computational nonlinear dynamics — how organized motion persists in systems governed by simple rules, and when a high-dimensional system genuinely admits a faithful low-dimensional description. The same thread runs through periodic orbits and limit cycles, quasi-periodic tori, bounded chaos, and localized coherent structures — from rotorcraft stability to fluid–structure dynamics to continuous cellular automata like Lenia.
Recurrence & coherent structures
A recurrent or coherent object can be recognized by applying an evolution operator and measuring a residual: how far the state fails to close on itself, possibly after a symmetry or in a moving frame. One language covers exact periodic motion, quasi-periodic near-returns, bounded chaotic recurrence, and local coherent structures — read together with Floquet multipliers and Lyapunov exponents to tell them apart.
When is a reduced model actually closed?
I study when a compressed feature evolves on its own, weakly coupled to the unresolved degrees of freedom, through a closure residual — a forward-pass–only diagnostic. It turns “is this reduced description valid?” into a number, and travels from Lenia gliders and fluid–structure features to activation-steering directions in large language models on a single consumer GPU.
Contact
Como, Italy · open to collaboration on microgravity fluid dynamics, reduced-order modeling and coupled CFD–multibody simulation.