GE Explores Dust Effects on Turbine Engine Operations

Designing and manufacturing turbine engines is an enormously complex process, and OEMs such as GE Aerospace deploy significant amounts of money and resources to deliver a reliable and maintainable product with the performance needed by aircraft manufacturer and operator customers.

One of the subtle factors that most aviation industry observers might not be aware of is the effect of dust on turbine engines. In certain environments, dust is a critical factor and can hamper operations and engine life.

To ensure that its engines can safely handle these conditions, GE runs operational dust-ingestion tests to optimize for durability. These tests were done on earlier programs, as well as the Leap, and more recently on the Rise program’s high-pressure turbine airfoils.

According to GE, “Dust-ingestion testing uses a proprietary mix of sand and other particles developed by GE Aerospace.” Ordinary sand and dust particles gathered from Middle East environments weren’t suitable for engine testing, according to a GE spokesman, which is why the company needed to develop its own proprietary particles.

Once the particles are prepared, GE uses a specialized test rig to inject the dust into the engine during thousands of cycles of testing. This includes takeoff, climb, cruise, and landing. “The test campaign will replicate how the parts would withstand flight conditions in severe operating environments around the world, [which is] important for customer operations,” according to GE.

In a YouTube video about Leap development, GE explained that, in the Middle East, “fine dust can block cooling holes in our high-pressure turbine blades, creating greater material stress when the engine runs hot. Turning on those conditions in a test cell turned out to be very, very difficult.”

“You can’t just go out into an environment where we have challenges in the Middle East, scoop up a little dust, and throw it into the engine,” said Carlos Perez, general manager, services engineering. “It doesn’t work that way.”

Getting the GE-developed dust into the right place in the engine for the tests is difficult. “This is actually a critical scientific activity that took us 15 years and two PhD geologists to help us resolve.” Ultimately, there were 14 iterations and thousands of hours of testing of various dust blends on earlier engines before GE perfected the blend.