Gas turbine engine with a microwave generator

#This specification is based upon and claims the benefit of priority from United Kingdom patent application number GB 1901320.0 filed on Jan. 31, 2019, the entire contents of which are incorporated herein by reference.

#The present disclosure relates to gas turbine engines and more particularly to apparatus and methods for controlling operation of gas turbine engines, e.g. in order to reduce emissions from gas turbine engines.

#Reducing emissions from aircraft gas turbine engines is desirable, in order to lessen environmental impact of aircraft operations. Further, ever-tightening environmental legislation in many areas of the world means that reducing emissions from aircraft gas turbine engines may be imperative, and not merely desirable, for aircraft operators, e.g. airlines, to be able to continue operating in such areas in future.

#Embodiments will now be described by way of example only, with reference to the Figures, in which:

#FIG. 1 is a sectional side view of a gas turbine engine;

#FIG. 2 is a close up sectional side view of an upstream portion of a gas turbine engine;

#Aspects and embodiments of the present disclosure will now be discussed with reference to the accompanying figures. Further aspects and embodiments will be apparent to those skilled in the art.

#FIG. 1 illustrates a gas turbine engine 10 having a principal rotational axis 9. The engine 10 comprises an air intake 12 and a propulsive fan 23 that generates two airflows: a core airflow A and a bypass airflow B. The gas turbine engine 10 comprises a core 11 that receives the core airflow A. The engine core 11 comprises, in axial flow series, a low pressure compressor 14, a high-pressure compressor 15, combustion equipment 16, a high-pressure turbine 17, a low pressure turbine 19 and a core exhaust nozzle 20. A nacelle 21 surrounds the gas turbine engine 10 and defines a bypass duct 22 and a bypass exhaust nozzle 18. The bypass airflow B flows through the bypass duct 22. The fan 23 is attached to and driven by the low pressure turbine 19 via a shaft 26 and an epicyclic gearbox 30.

#In use, the core airflow A is accelerated and compressed by the low pressure compressor 14 and directed into the high pressure compressor 15 where further compression takes place. The compressed air exhausted from the high pressure compressor 15 is directed into the combustion equipment 16 where it is mixed with fuel and the mixture is combusted. The resultant hot combustion products then expand through, and thereby drive, the high pressure and low pressure turbines 17, 19 before being exhausted through the core exhaust nozzle 20 to provide some propulsive thrust. The high pressure turbine 17 drives the high pressure compressor 15 by a suitable interconnecting shaft 27. The fan 23 generally provides the majority of the propulsive thrust. The epicyclic gearbox 30 is a reduction gearbox.