UK aerospace engine manufacturer Rolls-Royce is developing "world-first" technology for the Tempest future fighter project, the company announced on 10 January.
The effort, which has to date been running for five years, is geared towards managing "unprecedented levels of electrical power demand and thermal load … within the context of a stealthy aircraft." The goal is to provide both the thrust to propel the aircraft and the electrical power required for all the systems, while managing the resulting thermal loads.
According to Rolls-Royce, the Tempest effort builds on earlier work to address future aircraft power demands. In 2014 it designed an electrical starter-generator that was fully embedded in the core of a gas turbine engine, now known as the Embedded Electrical Starter Generator (E2SG) demonstrator programme.
"The electrical embedded starter-generator will save space and provide the large amount of electrical power required by future fighters. Existing aircraft engines generate power through a gearbox underneath the engine, which drives a generator. In addition to adding moving parts and complexity, the space required outside the engine for the gearbox and generator makes the airframe larger, which is undesirable in a stealthy platform," Conrad Banks, Chief Engineer for Future Programmes at Rolls-Royce was quoted as saying.
As Rolls-Royce explained, the two-spool-mounted electrical machines enable, by combination of operation as either a motor or a generator, the production of a series of functional effects on the engine, including the transfer of power electrically between the two spools.
Phase two of the E2SG programme, launched in 2017, has now been adopted as part of Rolls-Royce's contribution to the Tempest programme. This phase saw the inclusion of a second electrical generator connected to the other spool of the engine. It also included an energy storage system in the electrical network and the ability to intelligently manage the supply of power between all these systems.