Engineers at GE Global Research are laying claim to achieving the highest combination of temperatures ever recorded inside the compressor of a turbine engine. The developmental engine program is a cooperative research project between GE and the Air Force Research Laboratory. It’s called ADVENT (Adaptive Versatile Engine Technology) and makes heavy use of ceramic matrix composites (CMCs).
Ceramics, with their great resistance to high temperatures, have long been considered a possible material for allowing higher temperatures in jet engines. But until the development of CMCs, they were thought to be too fragile for the hostile environment inside a jet engine. Last July, GE announced it had completed close to 1 million hours’ testing of the technology, including more than 15,000 hours in land-based gas turbines used to generate electricity. Materials scientist Jim Vartuli said, “This material is ready for flight.”
CMCs can withstand temperatures up to 2,400 degrees Fahrenheit – far hotter than any metal alloy currently in use in jet engines. That means that strategies used to keep metals cool (at the cost of power and efficiency) will not be needed with CMC engines. GE expects to see increases in thrust of 10 percent, fuel efficiency of 25 percent and aircraft cruising range of up to 30 percent. The ADVENT design combines the efficiency of a high-bypass fan engine with the raw power of a military engine.
“It’s pure thermodynamics,” said Rick Albrecht, manager for advanced military systems at GE Aviation.