The numerical investigation of spindle torque for a controllable pitch propeller in feathering maneuver

Abstract

Present paper studies the variation of the blade spindle torque in a controllable pitch propeller (CPP) during the feathering maneuver, which is one of the rare but most challenging propeller maneuvers in CPP operation. The knowledge of the spindle torque under different operating conditions is one of the key features for the CPP controller unit design. The aim of this study is determining the forces needed to be governed to control the blade motion of a CPP converted from a fixed pitch propeller and the scale effect on these forces. So as to obtain a realistic numerical setup, the time-dependent superposed motion of the main rotation of the propeller and the rotation of each blade around its axis is modeled using a hybrid overset/sliding mesh technique. The spindle torque values were calculated during the dynamical variation of the blade pitch in feathering maneuver, and a novel expression is recommended to non-dimensionalize the predicted spindle torque. The result revealed that the required torque values to rotate each blade during the propeller maneuver is rising up to a critical pitch angle. Further increment of the pitch angle results in lower spindle torque values. Furthermore, this critical pitch angle is inversely proportional to the propeller loading.

Numerical Investigation into the Effect of Duct Use on the Performance of Controllable Pitch Propellers

“…The thrust coefficient, torque coefficient, and propeller efficiency have been analyzed based on the advance ratio, as frequently used in the literature, in order to determine the propeller operating performance. The results are also discussed in terms of the spindle torque coefficient as proposed by Yurtseven and Aktay (2023).…”

“…This introduces the concept of spindle torque, which is not present in fixed-pitch propellers. A few studies are also found in the literature on the propeller blade spindle torque of CPP propellers (Godjevac et al, 2009;Jessup et al, 2009;Martelli et al, 2013;Tarbiat et al, 2014;Pourmostafaet al, 2021;Yurtseven et al, 2023). Determining blade spindle torques is also very important for aiding the design of CPP propellers and for avoiding excessive blade actuation pressures at the blade hub (Liu et al, 2015).…”