Ceramic Composites and Thermal Protection Systems for Reusable Re-Entry Vehicles

2006 ◽  
Vol 45 ◽  
pp. 1505-1514 ◽  
Author(s):  
Teodoro Valente ◽  
Cecilia Bartuli ◽  
Giovanni Pulci
Keyword(s):  
High Temperature ◽  
Thermal Protection ◽  
Space Vehicle ◽  
Ceramic Composites ◽  
Heat Fluxes ◽  
Launch Vehicles ◽  
Processing Technologies ◽  
Reusable Launch Vehicles ◽  
Expected Benefits ◽  
The Right

Next generation of reusable launch vehicles and new hypersonic space vehicle concepts are currently under development, moving from traditional aerodynamic configuration towards slender profiles. Main expected benefits are reduction of drag, enhancement in lift-to-drag ratio and reduction of interferences with radio frequency transmissions during the re-entry. Flexibility in designing sharp profiles is strictly conditioned to the availability of suitable materials and processing technologies, required to fabricate components and surfaces able to withstand higher heat fluxes induced by the new profiles. Advances in the field of CMC's for high temperature structures and TPS are the basis for innovative approaches to the design of future RLV's. Beside baseline solutions, already available and well characterized, as for C/SiC CMC's, ultra high temperature ceramics seem to offer the right chance to fabricate hot structures having the required heat-resistant and load carrying capabilities. This paper deals with technologies based on the use of diboride based CMC's which can be considered promising candidate materials for the fabrication of hot structures of slender bodies, such as nose cap and wing leading edges. Recent experimental results will be presented and discussed.

AERO-THERMO-DYNAMIC STUDY OF ULTRA-HIGH- TEMPERATURE CERAMIC COMPOSITES FOR THERMAL PROTECTION SYSTEMS AND ROCKET NOZZLES

2021 ◽  
Author(s):  
STEFANO MUNGIGUERRA ◽  
ANSELMO CECERE ◽  
RAFFAELE SAVINO
Keyword(s):  
High Temperature ◽  
Thermal Protection ◽  
Ceramic Composites ◽  
Thermal Protection Systems ◽  
Research Activities ◽  
Ablation Resistance ◽  
Protection Systems ◽  
Project Objectives ◽  
Ultra High Temperature

The most extreme aero-thermo-dynamic conditions encountered in aerospace applications include those of atmospheric re-entry, characterized by hypersonic Mach numbers, high temperatures and a chemically reacting environment, and of rocket propulsion, in which a combusting, high-pressure, supersonic flow can severely attack the surfaces of the motor internal components (particularly nozzle throats), leading to thermo-chemical erosion and consequent thrust decrease. For these applications, Ultra-High-Temperature Ceramics (UHTC), namely transition metal borides and carbides, are regarded as promising candidates, due to their excellent high-temperature properties, including oxidation and ablation resistance, which are boosted by the introduction of secondary phases, such as silicon carbide and carbon fibers reinforcement (in the so-called Ultra-High- Temperature Ceramic Matrix Composites, UHTCMC). The recent European H2020 C3HARME research project was devoted to development and characterization of new-class UHTCMCs for near-zero ablation thermal protection systems for re-entry vehicles and near-zero erosion rocket nozzles. Within the frame of the project and in collaboration with several research institutions and private companies, research activities at the University of Naples “Federico II” (UNINA) focused on requirements definition, prototypes design and test conditions identification, with the aim to increase the Technology Readiness Level (TRL) of UHTCMC up to 6. Experimental tests were performed with two facilities: an arc-jet plasma wind tunnel, where small specimens were characterized in a relevant atmospheric re-entry environment (Fig.1a), and a lab-scale hybrid rocket engine, where material testing was performed with different setups, up to complete nozzle tests, in conditions representative of real propulsive applications (Fig.1b). The characterization of the aero-thermo-chemical response and ablation resistance of different UHTCMC formulations was supported by numerical computations of fluiddynamic flowfields and materials thermal behavior. The UNINA activities provided a large database supporting the achievement of the project objectives, with development and testing of full-scale TPS assemblies and a large-size solid rocket nozzle.

scholarly journals Thermochemical characterization of polybenzimidazole with and without nano-ZrO2 for ablative materials application

2020 ◽  
Vol 142 (5) ◽  
pp. 2149-2161
Author(s):  
L. Paglia ◽  
V. Genova ◽  
M. P. Bracciale ◽  
C. Bartuli ◽  
F. Marra ◽  
...  
Keyword(s):  
High Performance ◽  
Phenolic Resin ◽  
Thermal Protection ◽  
Space Vehicle ◽  
Heat Fluxes ◽  
Heating Rates ◽  
Thermoplastic Material ◽  
Environmental Friendly ◽  
Very High

AbstractDuring the ballistic atmospheric re-entry, a space vehicle has to withstand huge thermo-mechanical solicitations because of its high velocity and the friction with the atmosphere. According to the kind of the re-entry mission, the heat fluxes can be very high (in the order of some MW m−2) ;thus, an adequate thermal protection system is mandatory in order to preserve the structure of the vehicle, the payload and, for manned mission, the crew. Carbon phenolic ablators have been chosen for several missions because they are able to dissipate the incident heat flux very efficiently. Phenolic resin presents satisfying performance but also environmental drawbacks. Thus, a more environmental-friendly solution was conceived: a high-performance thermoplastic material, polybenzimidazole (PBI), was employed instead of phenolic resin. In this work PBI-ablative material samples were manufactured with and without the addition of nano-ZrO2 and tested with an oxyacetylene flame. For comparison, some carbon-phenolic ablators with the same density were manufactured and tested too. Thermogravimetric analysis on PBI samples was carried out at different heating rates, and the obtained TG data were elaborated to evaluate the activation energy of PBI and nano-filled PBI. The thermokinetics results for PBI show an improvement in thermal stability due to the addition of nano-ZrO2, while the oxyacetylene flame test enlightens how PBI ablators are able to overcome the carbon phenolic ablators performance, in particular when modified by the addition of nano-ZrO2.

Sign in / Sign up

Export Citation Format

Share Document