Characterisation of Polyurethane-urea as Leading-Edge Erosion Resistant Materials of Wind Turbine Blades

Abstract

Surrounded by oceans, building offshore wind turbines is a great strategy for archipelago countries, like Indonesia, to harvest renewable energy from wind. However, because of high rainfall rate, water droplet erosion on wind turbine blades is inevitably to be one of the most challenging problems. It causes decreasing produced energy and increasing cost of maintenance and repairment. A novel coating material which has better mechanical properties is therefore required. As a preliminary step, this work aims to characterise thermal and mechanical properties of soft and hard polyurethane-urea (PUU). In this work, the materials are soft PUU30 which has a hardness of 30 shore A, and hard PUU95 which has a hardness of 95 shore A. Thermal properties are characterised by Differential Scanning Calorimetry (DSC), while mechanical properties are investigated by tensile test at various strain rates. The results show that PUU95 has a higher strain rate dependence on modulus, tensile strength, and strain at break, which need to be considered for application regarding the range of wind speeds.