Back to the original topic of the thread: I felt it helpful to take a look at the TOS Klingon Battlecruiser that does not have any rotating or glowing thingies, but probably just as the Enterprise
needs the intake of stellar matter for warp drive and/or to replenish fuel.
The forward structure of the Klingon Battlecruiser's engineering hull reminded me a lot of the intake configuration of the UK's Sea Hawks
jet fighters (considering that Matt Jefferies was quite a fan of aviation, that's possibly where he drew his inspiration for the Klingon Battlecruiser design from). I'd say that's where the Klingon ships suck in interstellar matter.