What is a Turbine gerotor fuel pump?

Answer 1

A turbine pump has a disk with fins on the edge of it spinning between 2 plates that have grooves almost all the way around, the fins "drag" the fuel in the inlet and around the groove till it hits the end where it exits at high pressure. The drain pump on older Maytag upright (top load) clothes washing machines is also a turbine pump, but it is large and spins slower hence it develops high flow volume not high pressure.

A gerotor pump has one gear spinning inside another, the inner gear always has 1 less tooth than the outer, IE 5 teeth on the inner and 6 on the outer, the teeth are also rounded so that they are always in contact. Since there are different numbers of teeth there are pockets formed that are constantly getting larger and smaller as the gears turn, these pockets are used to pump the fuel. The engine oil pump and auto Transmission Fluid pump are usually also gerotor designs.

In general a turbine pump will be quieter than a gerotor since its moving parts don't touch anything, they just spin, where the gerotor always has some whine from the gear noise.