The present invention concerns a power generating apparatus for generating power from a fluid flowing in a pipe (14). The apparatus includes a cylindrical body (13), and an annular turbine (4) for driving an electric generator. Fluid bearings (8, 9, 10) support the turbine (4). A central flow passage (17) extends through the entire power generating apparatus. A fluid conditioner stage removes contamination of solid particles from the fluid, for conditioning the fluid before entering the fluid bearing (8, 9, 10), lubricated by the fluid. A first static flow shaper (1) is included in the fluid conditioner stage for providing a rotating vortex flow acting to concentrate the contamination of solid particles in a flow along an outer circumference of the apparatus and an uncontaminated flow to the bearings (8, 9, 10).