Not Your Mother's Ceramics

September 05, 2014 in Technology, Environment

This summer, Boeing successfully flight tested an innovative engine nozzle made of ceramic composites designed to reduce noise, weight and lower fuel use.

The ceramic matrix composite (CMC) nozzle went through a series of tests on the ecoDemonstrator 787 Flight Test Airplane, including community noise testing, passing over a large acoustic array in Moses Lake, Wash.

Boeing engineers have been working on the technology over the last five years so seeing all their hard work come to fruition is a great accomplishment, said Mitch Petervary, the technology’s principal investigator.

“This program began years ago with small samples in labs, and now we have flight tested the largest built oxide CMC structure in the world, and it performed at a very high level,” Petervary said. “Our innovative team has worked so hard to get to this point. Seeing our technology in the sky is remarkable and is a testament to what we can achieve.”

This flight demonstration is part of the five-year FAA Continuous Lower Energy, Emissions and Noise (CLEEN) program. Boeing is one of five industry contractors participating in CLEEN, an open, competitively bid, cost share program focused on speeding up development of new technologies that improve airplane fuel efficiency and decrease emissions and noise.

“The nozzle is a great example of how we develop and mature technology solutions faster. The team performed extremely well, and the testing completed without a hitch,” said Craig Wilsey, Boeing’s CLEEN program manager. “We really moved the needle on a technology that can benefit everyone.”

“The FAA CLEEN Program is very excited to see Boeing’s ceramic matrix composite exhaust nozzle fly,” said Arthur Orton, FAA CLEEN program engineer. “The flight test of the CMC nozzle is a major milestone for this technology.  Innovative technologies such as this are needed to help meet FAA’s NextGen environmental goals, and represents excellent progress for the CLEEN Program.”

So why is Boeing interested in CMC technology for engine nozzles? It’s all about performance.

Modern engines have higher operating temperatures to achieve improved fuel efficiency and reduce emissions. However, these hotter temperatures are pushing the capabilities of current metallic components used. CMC technology is lighter than current metallic components and can last longer in the higher temperatures.

Special CMC designs are also capable of having acoustic treatments built into them  that help make engines quieter, lighter and more efficient. This technology can also enable new, dramatically different engine designs in the future.

And these aren’t your mother’s ceramics.

The material used in CMC technology has a structural resiliency more similar to wood than to that of, say, a fragile tea cup or vase, for example.

This fall, the 787 is scheduled to flight test more than 30 additional ecoDemonstrator technologies aimed at improving operational efficiency, reducing fuel use, and achieving quieter operation. The ecoDemonstrator program is Boeing’s development and test program that focuses on improving environmental performance by bringing new technologies, materials and methods to implementation faster than ever before.