The first core of CFM International's advanced LEAP-X development program, eCore 1, has successfully completed the first phase of testing in a special altitude test chamber at GE Aviation facilities in Evendale, Ohio. The core, which began testing on schedule on June 12, 2009, ran for approximately 35 hours.
LEAP-X is the new centerline engine being developed to power the next-generation of short-to-medium range aircraft likely to enter the market in the next decade. The first full demonstrator engine is scheduled to run in 2012, and LEAP-X could be certified by 2016.
"For this first phase, we focused on the combustor and the high-pressure turbine," said Ron Klapproth, LEAP program director for CFM International. "And we couldn't be happier with the results. The hardware met all of our expectations and then some. Now, we going to focus on the high-pressure compressor."
The heavily instrumented core, which is scheduled to go back on test in early 2010, tests approximately 2,000 different engine parameters. The unique core test facility allows CFM to put the hardware through its paces by simulating both ground and altitude conditions over a much greater operating range than could be conducted with a full engine test. It allows engineers to see how the core behaves outside of standard operating conditions at extremes the hardware would never encounter in typical commercial airline service.
"Our engines operate an average eight to 10 cycles per day and, in that environment, reliability simply cannot be compromised," said Klapproth. "That is why we will be running multiple core tests over the next few years. We will complete these tests well in advance of the earliest entry into service to ensure our customers that we will provide their operators with absolutely the highest levels of reliability from day one."
The current test program focuses on aerodynamic performance parameters; the aeromechanical properties of the blades and how they respond to vibration and natural frequencies; and operability to ensure the engine maintains the CFM reputation for stall-free operation. All of the data collected from these tests will feed into eCore 2, which features a two-stage turbine and is on schedule to get ground tests in mid-2011.
Another technology highlight of the revolutionary LEAP-X engine include the 3-D Woven Resin Transfer Molding (RTM) composite fan and case.
This Snecma proprietary technology has been under development for several years and will dramatically reduce engine weight while providing a more durable blade. In January 2009, CFM initiated ground test of a full-scale RTM fan installed on a CFM56-5C engine. The program, dubbed MASCOT (Moteur a Aubes de Soufflante en COmposite Taille), is validating this revolutionary technology in a CFM-sized fan.
At Snecma facilities in Villaroche, France, the MASCOT engine completed aerodynamic and performance testing before going to Peebles. It has successfully completed extensive crosswind testing and is currently undergoing acoustics testing to measure noise levels under various operating conditions.
The engine has been returned to France and is scheduled to begin a grueling 5,000-cycle endurance test in early 2010.
Results to date are very positive and are inline with pre-test expectation and CFM will continue to refine and test various blade designs to identify the optimum configuration for the first LEAP-X demo engine test in 2012. The LEAP-X fan will feature 18 blades, a 50 percent reduction versus the CFM56-5C and 25 percent fewer blades than the CFM56-7B.
The goals for LEAP-X include reducing the engine contribution to aircraft fuel burn by up to 16 percent compared to current CFM56 Tech Insertion engines that power Airbus A320 and Boeing Next-Generation 737 aircraft. Additional fuel burn improvements will be achieved once this engine is paired with new aircraft technology. This will bring a comparable improvement in CO2 emissions. LEAP-X is also being designed to reduced NOx emissions by 50 - 60 percent compared to the current International Civil Aviation Organisation (ICAO) CAEP 6 limits. The incorporation of advanced composite materials and alloys will help reduce engine weight and contribute to the lower fuel burn.
The foundation of the LEAP-X engine is heavily rooted in advanced aerodynamics, environmental, and materials technology development programs. In addition to Snecma's RTM fan, GE has been developing Ceramic Matrix Composite (CMC) technology for more than 25 years. This ultra-light-weight material can support the extremely high temperatures found in the high-pressure turbine.