Rolls-Royce released their next-generation aerospace large engine in 2014, in which titanium alloy hollow fan blades are one of Rollo's core technologies.
It took them ten years to finally get a stable production process that meets the accuracy requirements, and finally got a very lightweight but extremely rugged design. Recently, Rolls-Royce officially released the fan manufacturing process.
In a furnace with a temperature of nearly 1000 ° C, three pieces of titanium plates connected together are expanded with argon gas to form accurately.
As the two outer titanium plates expand, the middle layer stretches into a core structure, giving the hollow blades extraordinary strength.
Observing millions of data points, the measurement accuracy reaches 40 microns, which is equivalent to half the diameter of human hair.
The robot polishes and scans, and uses a three-dimensional virtual model to detect any differences on the blades.
After so many years of development, we know that the space for optimizing the aerodynamic performance of aircraft is very limited, and everyone shifts the focus to how to further improve the engine's propulsion and combustion efficiency.
Rolls-Royce is expected to achieve major technological breakthroughs in civil engines in the next few years through the Advance and UltraFan projects.
Advance project
Under the Advance project, Rolls-Royce plans to build a next-generation turbofan engine series with a newly developed high-pressure core engine with a supercharge ratio exceeding 60. It is expected that the bypass ratio of Advance engines that will be put into use in 2020 will exceed 11, and the fuel consumption rate will be at least 20% lower than the current Trent 700.
UltraFan will further improve the medium-pressure turbine design on the basis of the Advance core engine and drive the fan through the gear system.
It is expected that the UltraFan engine that will be put into use after 2025 will use a gear-driven variable-pitch fan with a total boost ratio of 70, a bypass ratio of 15 and a fuel consumption rate that will be at least 25% lower than that of the Trent 700.
UltraFan engine performance
The CTi fan system of the UltraFan engine uses carbon fiber / titanium alloy fan blades and a composite hood. Each aircraft can lose 1500 pounds (680kg), which is equivalent to carrying seven passengers without increasing costs.
The variable speed design of the superfan engine will provide effective power for the future large thrust and high bypass ratio engine.
"Green" is not only reflected in the base color of carbon fiber / titanium alloy fan blades, but also means its energy saving and environmental protection effects: fuel saving, emission reduction and noise reduction.
The fuel consumption and emissions of the superfan engine will be 25% lower than that of the current Trent 700 engine, which is also the basic technology of the environmentally friendly engine (EFE) verification program.
Due to the low boost ratio of the fan, the pitch control is adopted so that it does not stall and flutter at non-designed speeds. The inclined and swept exit guide vanes and sound absorption treatment can effectively reduce noise.
The superfan engine nacelle is a cantilever nacelle with outlet guide vane support. This design eliminates the thrust reverser and greatly reduces the weight of the engine.
Removal of the thrust reverser can also reduce intake and exhaust losses, further reducing noise levels.
One of the core designs of the superfan engine, the "power gearbox", has completed a bench test in Germany a few days ago, and its output efficiency has reached 70,000 horsepower, which is another important milestone of the project.
The designed output power of the power gearbox will reach 100,000 horsepower, and the world's largest geared turbofan engine will be available soon.
UltraFan completed the first flight test on the Trent 1000 engine of the Boeing 747-200 flight platform at the test base in Arizona, USA in 2014.
Tests in the United States have shown that the fan performance is good, which is the project's first important milestone.
An optical fiber sensor is installed at the tip of the fan blade to monitor the health status of the fan.
Rolls-Royce invests 1.2 billion to 1.3 billion pounds in research and development annually.
The superfan engine is planned to be put into use in 2025. Currently, Pratt & Whitney's geared turbofan engine GTF has powered the Airbus A320neo, Bombardier C series, Mitsubishi Jet MRJ, Russian MC-21 and Amberway E Jet-E2. The revolutionary era is coming.