When perusing the Wikipedia article on the upcoming Rolls Royce UltraFan engine, I noticed that it cited an interesting bit of information from an Aviation Week article:
As the fan system is designed to vary pitch in all phases of flight, including landing, the nacelle will not include a thrust reverser.
I understand that a turboprop can enter the beta range in order to vary the blade pitch into the negative range in order to supply reverse thrust.
However, my understanding of the UltraFan was that it is to be a geared turbofan design with the fan and the core ducted inside a more-or-less conventional turbofan nacelle (minus the thrust reverser, apparently.)
My question, then, is how does the airflow work through this engine with negative fan blade pitch?
When the blade pitch goes negative, then the fan will be blowing air out the intake rather than sucking it in through the intake, no? Where then is the air coming from which is getting pushed out the front and where is the air coming from that is still needing to go in the normal flow direction through the core? Does the flow direction through the bypass ducts reverse?