Mass moment of inertia model development for the dynamic response of windpumps

Abstract

The main form of wind energy harnessing is where the wind turns a turbine to create torque. Rotational inertia is the storage of rotational energy in the form of a rotating or spinning mass. The Mass Moment of Inertia (MMoI) is related to the mass and geometry of an object, describing the distribution of mass around a rotational axis. The development of the mass moment of inertia model for the dynamic response of windpumps focusses on the intricate windpump systems, which play a vital role in providing essential water access to remote and off-grid areas. A review of existing literature underscores the historical importance and intricate design principles of the windpump system, providing a foundation for subsequent model development. An integrated mathematical model is derived to evaluate windpump systems, focussing on the dynamics of energy flow and the impact of MMoI. The model is then transferred from the theoretical foundation to simulation through software implementation. The simulations allow for a stepwise approach with a focus on data flow and in-depth system behaviour analysis. The developed windpump model is validated, subjecting it to real-world scenarios to ensure its relative accuracy. Methods of collecting dimesional and mass input of the model are described, together with a possible experimental setup for future research. The model is subjected to different input conditions to analyse the response to different MMoIs. Scenarios that simulate acceleration, deceleration, and variable input force to determine the effective MMoI range. The effect of the variation in MMoI is evaluated considering changes in the trends of shaft velocity, pumped water volume, and overall energy distribution. The study determines a specific MMoI range (75 − 125 kg - m2) for effective windpump system performance, while also highlighting future aspects to investigate as a continuation of this study. These include physical validation experiments, model refinements, and system enhancements, such as additional MMoI storage and synergistic wind-solar coupling. In essence, this research investigates the dynamics of windpumps, laying the foundation for enhanced operational efficacy and sustainable water provision in diverse and challenging environments.