Rain erosion resistance of injection moulded and compression moulded polybutylene terephthalate PBT
Title |
Rain erosion resistance of injection moulded and compression moulded polybutylene terephthalate PBT |
Publication year |
2018 |
Author |
Slot, Henk |
Co-Authors |
Nord-Varhaug, Katrin (Norner) - I.Jzerman Richard - Le Feber, Maaike - Van der Heidi, Emilie |
Source |
Wear 414-415 (2018) 234-242 |
Abstract |
Offshore wind turbine rotor diameters are expected to increase, giving rise to more severe raindrop impact conditions and related erosion of the wind turbine blades. Droplet impingement erosion tests were performed in the current work and compared to an extended and improved fatigue based erosion model, for injection moulded and compression moulded polybutylene terephthalate PBT. The latter material with continue fibre reinforcement would allow for even larger turbine blades. The developed erosion test set-up was based on a high water pressure nozzle system spraying water drops at a stationary PBT surface. Model results for heavy rain conditions with a droplet size of 1.8 mm and an impact velocity of 120 m/s are shown. Although a reasonable similarity between test results and model calculations for the injection moulding PBT was found, the absolute value of the incubation period predicted by the model for compression moulded PBT differed substantially. This probably resulted from the lower confidence level of the S-N curve for the compression moulded PBT and the large number of small droplets – with a diameter of about 0.030 – per time unit and area unit generated by this nozzle-equipped test apparatus. The droplet impingement measurements and model predictions both showed a substantially higher incubation period for injection moulded PBT compared to compression moulded PBT |