this, and emphasis should be placed on reliable, repairable, supportable active and passive systems that can be integrated into many missions.
3. Radiators: Develop improved space radiators with reduced mass.
Radiators are used for energy removal from spacecraft and planetary base systems and are mission-critical for many proposed missions. To reduce radiator mass, area, and pumping power, research is needed on variable emissivity, very low absorptivity-to-emissivity ratio, self-cleaning, and high-temperature coatings, as well as on lightweight radiators or compact storage systems for extending extravehicular activity capability.
4. Multifunctional Materials: Develop high-temperature multifunctional materials that combine structural strength, good insulating ability, and possibly other functions.
Multifunctional systems can provide significant mass savings, allowing increased payload weight. Multifunctional TPS and multi-layer insulation (MLI) systems that combine thermal, structural, or micrometeoroid and orbital debris (MMOD) and crew radiation protection could provide significant weight savings and enable long-duration missions, and can also be used for planetary habitat thermal and multifunctional protection.
5. Verification and Validation: Develop, verify, validate, and quantify uncertainty analysis requirements for new or improved comprehensive computer codes for thermal analysis.
Upgrades to predictive codes for ablation during re-entry heating are needed to include closely coupled multi-phase ablation and radiative heating into the flow simulations, with careful attention given to verification, validation, and uncertainty quantification.
6. Repair Capability: Develop in-space thermal protection system repair capability.
Repair capability is especially important for long-duration missions. TPS repair developed for Space Shuttle Orbiter TPS should be continued and expanded to provide a repair method for future spacecraft.
7. Thermal Sensors: Enhance thermal sensor systems and measurement technologies.
Operational instrumentation is necessary to understand anomalies, material or performance degradation and performance enhancements, and advanced science mission measurements.
TA14 High-Priority Technologies
Technology 14.3.1, Ascent/Entry TPS
Effective heat shields and thermal insulation during ascent and atmospheric entry are mission-critical for all robotic and human missions that require entry into a planetary atmosphere. Ascent/entry TPS is game-changing because it is necessary for every planetary atmospheric ascent and/or entry mission, including every mission for return to Earth. Particularly critical level 4 technology items are rigid ablative TPS, obsolescence-driven TPS materials and process development, multi-functional TPS, and flexible TPS.
Technology 14.1.2, Active Thermal Control of Cryogenic Systems
Low to zero boil-off of cryogenic fluids will be mission-critical for long-duration missions, and cannot be achieved with present technology. A goal of this technology is to develop an overall cryogenic system design that integrates active and passive technologies into an optimal system, as well as instrumentation and sensors to monitor fluid mass. Minimization of active system capacity through effective use of passive control should help increase overall system reliability. This technology can enable a wide variety of long-duration missions.