S. D. Miller
Miller Scientific Inc.,
United States
Keywords: Thermal Protection Systems (TPS), Uncertainty Quantification (UQ), hypersonic vehicles
Summary:
Efficient thermal management in extreme environments remains a limiting factor for advanced aerospace and defense platforms, where undersized or inconsistent thermal protection can directly constrain performance, survivability, and operational lifetime. Engineered ceramic- and carbon-based fiber compositions offer a mission-relevant pathway to reduce conductive and radiative heat transfer while enabling lighter, more efficient system designs. This presentation describes recent advances in custom fiber systems and textile-derived insulation architectures designed specifically for non-apparel, non-consumer applications requiring sustained exposure to high heat flux. The materials discussed combine ceramic fibers, carbon fibers, and inorganic particulate constituents arranged to control heat transfer through microstructural design rather than bulk thickness alone. Radiative heat transfer is mitigated through controlled opacification, scattering, and emissivity management, while conductive pathways are suppressed via tailored fiber morphology and inter-fiber contact control. Organic binders are used selectively as processing aids to enable scalable wet-laid and nonwoven manufacturing, providing green strength and compliance without serving as primary thermal or structural contributors. A central theme of this work is the integration of uncertainty quantification (UQ) directly into material development and manufacturing workflows to improve product consistency and reduce performance risk. By coupling high-fidelity thermal characterization with data-driven statistical models, variability in key thermal properties is quantified and systematically reduced. This approach establishes defensible performance bounds and repeatability metrics aligned with defense acquisition expectations for material reliability and readiness. The research is supported through a portfolio that includes Air Force Office of Scientific Research (AFOSR) funding focused on improving material consistency under dynamic thermal conditions, USDA support for improved fire shelter development, as well as collaboration with NASA to improve the efficiency of hypersonic and reentry vehicles through advanced fiber-based thermal systems. These efforts leverage representative environmental testing, multi-physics modeling, and system-level benchmarking to ensure relevance to operational heat-flux regimes. Key technical contributions include: 1. Engineered Fiber Compositions and Quantified Thermal Performance: Development of ceramic- and carbon-based fiber systems with controlled microstructure and composition. Measured reductions in effective heat transfer and improved thermal efficiency are demonstrated relative to baseline insulation materials, enabling tailoring for mission-specific thermal environments. 2. Manufacturing Consistency and Scalable Processing: Digitally informed control of fiber formation and post-processing stabilizes critical attributes such as fiber diameter distribution, particulate loading, and density uniformity. These advances support repeatable production and credible scale-up pathways. 3. System-Level Integration and Validation: Integration of engineered fibers into flexible textile and blanket architectures while preserving mechanical durability and manufacturability. Thermal testing under representative heat-flux loading confirms reductions in transmitted heat flux, validating system-level performance. In selected architectures, phase-change constituents are incorporated to block advection and buffer transient thermal loads, further extending performance margins without compromising structural integrity or process compatibility. Collectively, these results demonstrate a convergence of advanced materials design, manufacturing control, and predictive analytics aimed at advancing fiber-based thermal insulation technologies toward operational deployment. By emphasizing quantified performance gains, production consistency, and transition-focused metrics, this work supports the development of next-generation thermal protection systems for aerospace and defense applications.