Rolls-Royce (Chalet 93) says it is busy “proving our future core,” as the UK engine manufacturer prepares to move its newly-assembled Advance 3 test engine from its Bristol site to a test cell at its Derby headquarters next month.
Last week, AIN visited Bristol, where R-R’s main focus is military engines, to see the final touches being made to the test instrumentation on Advance 3. That engine will form the basis for the company’s next generation of civil powerplants, currently dubbed Advance (for engines to enter service in the 2020 timeframe) and UltraFan (for airframes in 2025 and beyond). They include a new Powered Gearbox (PGB), which is currently the focus of a major development effort at the R-R site in Berlin, Germany. It has a bypass ratio of around 4:1, so the UltraFan will be able to have a large, slow fan while the turbine can turn at its optimum speed. This marks R-R leaving behind its highly successful three-shaft architecture (common to all current Trent engines) for a “two-and-a-half-shaft" configuration, similar to Pratt & Whitney’s geared turbofans, but on a much larger scale.
The advance test engine shown consists of the new core, coupled with a Trent XWB fan and Trent 1000 LP turbine, said chief engineer commercial large engine future programs, Phil Curnock. He added that numerous new technologies were being inserted into Advance and tested in various sub-programs and demonstrators, such as its ALPS composite-titanium fan system and ALECSys advanced low-emissions combustion system (which recently completed altitude relight testing in Stuttgart). Curnock said the CTi fan has now reached TRL (Technology Readiness Level) 5. “We have a few more tests to complete and we’ll be at TRL 6,” he noted.
Rolls-Royce has already flight tested (last October) a Trent 1000, with a composite fan and titanium case, on its Boeing 747 flying testbed in the U.S.
Curnock said the company would “establish a drumbeat of regular testing” and was targeting 2021 for flight testing of an UltraFan engine.
Chief engineer and head of program for Advance 3, Andy Geer, said that the Advance 3 test engine would be trucked to Derby “in July” and would then be put on a test pylon before installing in one of the site’s large test cells. Tests will include water ingestion, noise surveys, X-ray examination, “rumble” survey and core zone thermal surveys, with the engine running at speeds of up to 15,000 rpm. Ultimately the technology will pave the way for Rolls-Royce’s future airliner engines with up to 50,000pounds of thrust, including the geared UltraFan, he said.