Kimon Silwal: Natural Materials and Coatings for Low Cost Wind Turbines for Developing Countries: Summary of Studies
Timbers are hygroscopic in nature. It has the ability to take in or give off moisture. The moisture content in the timber depends upon the amount of water content in the surrounding atmosphere. Moisture absorption changes the weight of timber as a result; it can affect the dynamic properties of the blades. Further exposure of timber blades to surrounding conditions will deteriorate the surface resulting in bending and cracking of the blade material. Hence Selection of proper coatings are necessary. The paper presents the effect of different weather condition such as temperature, humidity and rainfall to change in weight of different Nepalese timber with application of several locally available low cost coatings. The regression model of the weather condition in percentile change in weight of timber with different coatings is determined and presented in this paper.