Sustaining Mature Thermal Protection Systems Crucial for Future In-Situ Planetary Missions

This paper shows three different joining methods for fibre ceramic materials. The so called in-situ joining method is an integral part of the manufacturing process for CMC structures via the liquid silicon infiltration (LSI) process. Stiffening elements, local patches within attachment areas, inserts etc. are permanently joined to shell structures, thus enabling highly integrated components to be realised with low manufacturing costs. Mechanical joining methods are required for the attachment of CMC thermal protection systems and the assembly of large structures which can not be manufactured as one part due to the limited size of manufacturing devices (e.g. autoclave, furnaces). For these cases, two different principles are available. The first method takes advantage of interlocking effects of hardened castable ceramics for permanent joints and the so called ceramic rivet, which has similar properties to metallic rivets, however using only elastic and frictional properties of the CMC basic material. The last joining method presented within this paper deals with the attachment of hot structures to a cold substructure. To solve the problems associated with thermal mismatch, elastic or kinematic attachment systems, well adapted to the thermal expansion behaviour are suitable candidates.

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Damage detection and localisation of CMCs by means of electrical health monitoring

CEAS Aeronautical Journal ◽

10.1007/s13272-020-00460-z ◽

2020 ◽

Vol 11 (4) ◽

pp. 929-935

Author(s):

Tina Staebler ◽

Hannah Boehrk ◽

Heinz Voggenreiter

Keyword(s):

Health Monitoring ◽

Electrical Resistance ◽

Thermal Protection ◽

Sample Length ◽

Thermal Protection Systems ◽

Spatially Resolved ◽

Switching Unit ◽

Protection Systems ◽

Sample Width

Abstract Carbon-based composites such as C/C-SiC are used in thermal protection systems for atmospheric re-entry. The electrical properties of this semiconductor material can be used for health monitoring, as electrical resistivity changes with damage, strain, and temperature. In this work, electrical resistance measurements are used to detect damage in a thermal protection system made of C/C-SiC. This can be done in-situ. Damage experiments with $$320\,\hbox {mm}\,\times \,120\,\hbox {mm}\,\times \,3\hbox { mm}$$ 320 mm × 120 mm × 3 mm panel shaped samples were conducted with a multiplexer switching unit to determine up to 288 electrical resistance and voltage measurements per cycle time and spatially resolved. The change in resistance is an indicator for damage, and with the use of post-processing algorithms, the location of the damage can be determined. With these data, inhomogeneous temperatures can be accorded for and damage can be detected. This method reacts even to small damages where less than 0.02% of the monitored surface is damaged. A localisation with a deviation from the real defect of less than 8% in sample width and 17% in sample length is presented.

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DEVELOPMENT OF ABLATIVE THERMAL RESPONSE MODELING OF EPDM-BASED THERMAL PROTECTION SYSTEMS

International Journal of Energetic Materials and Chemical Propulsion ◽

10.1615/intjenergeticmaterialschemprop.2020033869 ◽

2020 ◽

Vol 19 (4) ◽

pp. 275-292

Author(s):

Ramin Shilav ◽

Savely Khosid

Keyword(s):

Thermal Protection ◽

Thermal Response ◽

Thermal Protection Systems ◽

Protection Systems ◽

Response Modeling

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Trends in the development of flexible thermal protection systems for modern aircraft

Perspektivnye Materialy ◽

10.30791/1028-978x-2020-6-10-21 ◽

2020 ◽

pp. 10-21

Author(s):

V. G. Babashov ◽

◽

N. M. Varrik ◽

Keyword(s):

High Temperature ◽

Thermal Protection ◽

Heat Removal ◽

Operating Conditions ◽

Passive Protection ◽

Thermal Protection Systems ◽

Heat Protection ◽

Protection Systems ◽

Protected Surface ◽

Flexible Panels

The emergence of new types of space and aviation technology necessitates the development of new types of thermal protection systems capable of operating at high temperature and long operating times. There are several types of thermal protection systems for different operating conditions: active thermal protection systems using forced supply of coolant to the protected surface, passive thermal protection systems using materials with low thermal conductivity without additional heat removal, high-temperature systems, which are simultaneously elements of the bearing structure and provide thermal protection, ablation materials. Heat protection systems in the form of rigid tiles and flexible panels, felt and mats are most common kind of heat protecting systems. This article examines the trends of development of flexible reusable heat protection systems intended for passive protection of aircraft structural structures from overheating.

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Mechanical Stability of Hybrid Corrugated Sandwich Plates under Fluid-Structure-Thermal Coupling for Novel Thermal Protection Systems

Applied Sciences ◽

10.3390/app10082790 ◽

2020 ◽

Vol 10 (8) ◽

pp. 2790

Author(s):

Wenzheng Zhuang ◽

Chao Yang ◽

Zhigang Wu

Keyword(s):

Mechanical Stability ◽

Thermal Protection ◽

Element Model ◽

Parameter Study ◽

The Novel ◽

Thermal Coupling ◽

Mechanical Instability ◽

Fluid Structure ◽

Thermal Protection Systems ◽

Protection Systems

Hybrid corrugated sandwich (HCS) plates have become a promising candidate for novel thermal protection systems (TPS) due to their multi-functionality of load bearing and thermal protection. For hypersonic vehicles, the novel TPS that performs some structural functions is a potential method of saving weight, which is significant in reducing expensive design/manufacture cost. Considering the novel TPS exposed to severe thermal and aerodynamic environments, the mechanical stability of the HCS plates under fluid-structure-thermal coupling is crucial for preliminary design of the TPS. In this paper, an innovative layerwise finite element model of the HCS plates is presented, and coupled fluid-structure-thermal analysis is performed with a parameter study. The proposed method is validated to be accurate and efficient against commercial software simulation. Results have shown that the mechanical instability of the HCS plates can be induced by fluid-structure coupling and further accelerated by thermal effect. The influences of geometric parameters on thermal buckling and dynamic stability present opposite tendencies, indicating a tradeoff is required for the TPS design. The present analytical model and numerical results provide design guidance in the practical application of the novel TPS.

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