Samuel Akatchi Ahizi

PhD Thesis

Meshless CFD and Reduced Order Modeling of Cryogenic Sloshing in Conformal Tanks for Hydrogen Aviation

Supervisors

Miguel Alfonso Mendez (UC3M, von Karman Institute for Fluid Dynamics, Université Libre de Bruxelles).

Abstract

This PhD project is to explore advanced numerical simulation approaches to support the safe operation of hydrogen-powered aviation by addressing the critical phenomenon of propellant sloshing. Under the airplane acceleration, sloshing may significantly impact the vessel stability and the tank structural integrity, particularly concerning vibration-induced fatigue in thin reservoir tank shells. The cryogenic nature of liquid hydrogen adds additional complexity due to poorly understood pressure drop effects, particularly in non-canonical geometries. Although the Finite-Volume Volume of Fluid (VoF) method is widely adopted for isothermal sloshing simulations, its capability to handle heat and mass transfer processes accurately remains limited due to its diffuse interface modeling approach. Consequently, novel meshless numerical methods will be investigated to overcome these limitations.

This research is guided by several core questions:
-Can meshless particle-based methods (SPH, MPS, GFDM) accurately model isothermal
sloshing in complex geometries?
-Can simulation results from meshless methods be used to establish effective Lagrangian
modal decomposition techniques?
-What potential do meshless methods hold for developing intrusive and non-intrusive
Reduced Order Models (ROMs)?
-Can isothermal Lagrangian CFD/ROM frameworks be effectively extended to account for non-
isothermal effects?
-Can Lagrangian ROMs serve as frameworks to support the design of passive and active
sloshing mitigation strategies?

Doctoral Meetings

2024-2025

Poster