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Title: Boron-Nitride Nanosheet-Based Thermal Barrier Coating for Micro-Combustor Performance Improvement
Abstract One of the major challenges in the development of micro-combustors is heat losses that result in flame quenching, and reduced combustion efficiency and performance. In this work, a novel thermal barrier coating (TBC) using hexagonal boron nitride (h-BN) nanosheets as building blocks was developed and applied to a Swiss roll micro-combustor for determining its heat losses with increased temperatures inside the combustor that contributes to improved performance. It was found that by using the h-BN TBC, the combustion temperature of the micro-combustor increased from 850 K to 970 K under the same thermal loading and operational conditions. This remarkable temperature increase using the BN TBC originated from its low cross-plane thermal conductivity of 0.4 W m−1 K−1to mitigate the heat loss from the micro-combustor plates. Such a low thermal conductivity in the h-BN TBC is attributed to its interfacial resistance between the nanosheets. The development of h-BN TBC provides an effective approach to improve thermal management for performance improvements of gas turbine engines, rocket engines, and all various kinds of micro-combustors.  more » « less
Award ID(s):
1706777
PAR ID:
10334949
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Journal of Energy Resources Technology
Volume:
144
Issue:
6
ISSN:
0195-0738
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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