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Ceramic Coating on Flexible External Insulation Blankets for Reusable Missions


Affiliations
1 Ceramic Matrix Products Division, Analytical Spectroscopy and Ceramics Group, PCM Entity, Vikram Sarabhai Space Centre, Thiruvananthapuram 695 022, India
 

Flexible thermal protection material (flexible external insulation; FEI) is used in the Reusable Launch Vehicle-Technology Demonstrator (RLV-TD) leeward region where multiple curvatures are present. FEI configuration has silica cloth layers on either side with Cerablanket felt sandwiched and stitched together using quartz thread. FEI should ensure an airframe skin temperature in the leeward region within the temperature constraint limits (100°C) of aluminum alloy during the RLV-TD ascent (4.8 W/cm2) and descent (3.7 W/cm2) phases. A ceramic room-temperature coating with low surface solar absorptivity (α) and high thermal emissivity (ε) to generate the required thermal gradient at the backwall was developed. The salient features of the ceramic coating are room-temperature curability, ease of application, minimum weight, durability, erosion resistance, stable optical characteristics, easily repairable, non-contaminating, high purity and high temperature compatibility with silica fabric. The properties of the ceramic coating are weight/area: 0.025–0.030 g/cm2, solar absorptivity the UV–VIS region: 0.12–0.18, IR emittance: >0.86, backwall temperature: <120°C (from kinetic heating simulation test).

Keywords

Emissivity, Flexible External Insulation, Protective Ceramic Coating, Reusable Missions.
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Abstract Views: 394

PDF Views: 128




  • Ceramic Coating on Flexible External Insulation Blankets for Reusable Missions

Abstract Views: 394  |  PDF Views: 128

Authors

Deepa Devapal
Ceramic Matrix Products Division, Analytical Spectroscopy and Ceramics Group, PCM Entity, Vikram Sarabhai Space Centre, Thiruvananthapuram 695 022, India
M. P. Gopakumar
Ceramic Matrix Products Division, Analytical Spectroscopy and Ceramics Group, PCM Entity, Vikram Sarabhai Space Centre, Thiruvananthapuram 695 022, India
P. V. Prabhakaran
Ceramic Matrix Products Division, Analytical Spectroscopy and Ceramics Group, PCM Entity, Vikram Sarabhai Space Centre, Thiruvananthapuram 695 022, India
S. Packirisamy
Ceramic Matrix Products Division, Analytical Spectroscopy and Ceramics Group, PCM Entity, Vikram Sarabhai Space Centre, Thiruvananthapuram 695 022, India

Abstract


Flexible thermal protection material (flexible external insulation; FEI) is used in the Reusable Launch Vehicle-Technology Demonstrator (RLV-TD) leeward region where multiple curvatures are present. FEI configuration has silica cloth layers on either side with Cerablanket felt sandwiched and stitched together using quartz thread. FEI should ensure an airframe skin temperature in the leeward region within the temperature constraint limits (100°C) of aluminum alloy during the RLV-TD ascent (4.8 W/cm2) and descent (3.7 W/cm2) phases. A ceramic room-temperature coating with low surface solar absorptivity (α) and high thermal emissivity (ε) to generate the required thermal gradient at the backwall was developed. The salient features of the ceramic coating are room-temperature curability, ease of application, minimum weight, durability, erosion resistance, stable optical characteristics, easily repairable, non-contaminating, high purity and high temperature compatibility with silica fabric. The properties of the ceramic coating are weight/area: 0.025–0.030 g/cm2, solar absorptivity the UV–VIS region: 0.12–0.18, IR emittance: >0.86, backwall temperature: <120°C (from kinetic heating simulation test).

Keywords


Emissivity, Flexible External Insulation, Protective Ceramic Coating, Reusable Missions.

References





DOI: https://doi.org/10.18520/cs%2Fv114%2Fi01%2F137-143