Dynamic Stall Characteristics and Modelling of Time-Varying Pitching Kinematics

TL;DR

This paper investigates how complex pitching motions affect dynamic stall behavior and evaluates a model's ability to predict force responses, proposing modifications for better accuracy in time-varying scenarios.

Contribution

It provides new insights into dynamic stall under complex kinematics and extends the Goman-Khrabrov model for improved prediction accuracy.

Findings

Pitching kinematics complexity influences stall delay and forces.

Pitch rate at static stall angle is insufficient for predicting stall onset.

Modified Goman-Khrabrov model better predicts force responses in complex motions.

Abstract

We present an experimental investigation examining how the complexity of pitching kinematics influences dynamic stall characteristics, including the stall delay and aerodynamic force response. The study examines whether the pitch rate defined at the static stall angle adequately characterises time-varying pitching kinematics for stall onset prediction. We then evaluate the performance of the generalised Goman-Khrabrov model in predicting force responses of nonlinear pitching motions and propose necessary modifications to extend the model's applicability to complex kinematics.