The current mechanical design of the counter rotating RPT was created using the CAD software PTC Creo Parametric. This design will be tested in the experiment and later validated in the CFD.
With the help of two bellows couplings, a possible misalignment between the motor shaft and the drive shaft can be compensated. The torque is measured by a torque meter between the couplings. The star-shaped arrangement of the supports of the horizontal unit in the tube results in the least possible influence on the flow with the greatest possible stability. A second support level in the same arrangement provides further stability.
Both, the drive shaft and the shaft inside the tube are supported by bearings in O-arrangement in order to be able to take the loads (of bevel gear and runner) outside the bearing unit. The distance between the two drive shafts has been chosen so that there is enough space for bearings and seals. The bevel gears withstand the loads calculated from the operating points and are lubricated with oil during operation.
Author – Jonas Oldeweme