HEATS

The employment of reusable vehicles is envisaged as the most promising strategy to reduce the costs of access to space, balancing efficiency and sustainability, as demonstrated by ESA Space Rider, devised to complement the Ariane and Vega launchers for the safe return on Earth. A space vehicle entering the Earth atmosphere with hypersonic velocity faces the harsh environment formed inside the shock layer. Similar conditions are encountered by hypersonic planes equipped with air-breathing propulsion systems (LAPCAT projects) designed for very rapid intercontinental flights. Hence, hypersonic vehicles need a suitable Thermal Protection System (TPS) which becomes the most vital subsystem representing a single point of failure. The TPS material must be a compromise between weight, thermal resistance, and catalytic activity in order to adequately reduce the heat flux at the surface, keeping as low as possible the mission costs. From an opposite point of view, the destructive hypersonic environment is desirable to prevent the potential danger of space debris falling on Earth. In these systems, the fate of the entering object is critically dependent on the intensity of the surface heat flux, which in turn is influenced by the object's geometrical characteristics, its chemical nature, and the physical-chemical phenomena occurring in the shock layer and at the surface. In fact, traveling at Mach number greater than 6, a shock wave forms with an abrupt change in the gas temperature and pressure: internal states are excited and chemical reactions, such as dissociation and ionization, are activated by collisions between particles, distributing thermal energy into a significant number of degrees of freedom and resulting in a marked non-equilibrium character of the distributions. The complex physics of hypersonic flights requires a suitable approach based on the detailed description of the kinetics in the fluid dynamics, accounting for the quantum nature of the matter. The project HEATS, funded by MUR under call PRIN PNRR 2022, aims to develop a computational tool able of coupling an accurate fluid dynamic simulation of the flow with advanced state-to-state chemical models accounting for microscopic collisional dynamics. The strength of the project relies, on the one hand, on the empowerment of the computational capabilities through the exploitation of GPUs and, on the other hand, on a complete chemistry including the ionization processes, relevant to super-orbital and lunar re-entry. Moreover, by accurately coupling such a tool with numerical algorithms able to describe the absorption of radiowaves in the plasma sheath, the communication blackout during the vehicle re-entry will be also studied. Finally, the interaction between the high enthalpy flow with the surface will be investigated in a hypersonic wind tunnel to test different TPS ceramic materials to extrapolate surface properties, needed in the simulations to estimate the role of catalysis and to validate the code.

DMMM Polytechnic University of Bari

Principal Investigator:
Francesco Bonelli
Unit expertise:

numerical methods for compressible and incompressible flows
code development and High-Performance Computing (HPC)
multi-phase and high-enthalpy flows in thermochemical non-equilibrium

CNR ISTP Bari

Co-PI & Unit Responsible:
Oreste Pezzi
Unit expertise:

non-equilibrium state-to-state kinetics
thermodynamics and transport of complex mixtures
plasma theory and numerical modeling of nearly-collisionless, turbulent space and astrophysical plasmas

University of Naples Federico II

Unit Responsible:
Anselmo Cecere
Unit expertise:

fluid dynamics for space science
techniques for thermo-fluid dynamic experiments in space environment
material testing in high-enthalpy flows

timeline

closeout
1Dec2025

M2
1June2025

First Year
1Dec2024

9&18October2024
project meetings
(Skype call)

17July2024
project meeting
(Skype call)

M1
1June2024

1March2024
project meeting
UniNA Lab

kickoff
5Dec2023

Experiment run on 1 March 2024 in the Plasma Wind Tunnel available at
the SPES (Small Planetary Entry Simulator) UniNa laboratory

Conferences
2024	Anselmo Cecere, Stefano Mungiguerra, Raffaele Costanzo, Antonio Esposito, Raffaele Savino “Flussi ipersonici: esperimenti in galleria al plasma ed applicazioni spaziali” Workshop “Tecnologie spaziali per le future missioni di ASI” 16-19 Aprile 2024, Italian Space Agency, Roma, Italy
	Francesco Bonelli, Gianpiero Colonna, Giuseppe Pascazio and Davide Ninni “Atmospheric re-entry flow simulations in ionization regime” 1st European Fluid Dynamics Conference (EFDC1) 16−20 September 2024, Aachen, Germany
	Francesco Bonelli, Davide Ninni, Gianpiero Colonna, Annarita Laricchiuta, and Giuseppe Pascazio “State-to-State investigation of hypersonic high-enthalpy nitrogen flows” 10th International Workshop on Radiation of High Temperature Gases 09–12 set 2024 University Oxford