To manufacture the optimal wind turbine blades, the speed ratio, TSR, which is defined as the ratio of the speed of the rotor tip to the wind speed, depends on the rotor blade shape profile, the number of turbine blades, and the wind turbine propeller blade design itself.
Generally, wind turbine blades are shaped to generate the maximum power from the wind at the minimum construction cost. But wind turbine blade manufacturers are always looking to develop a more efficient blade design. Constant improvements in the design of wind blades has produced new wind turbine designs which are more compact, quieter and are capable of generating more power from less wind. Its believed that by slightly curving the turbine blade, they’re able to capture 5 to 10 percent more wind energy and operate more efficiently in areas that have typically lower wind speeds. Therefore, the grinding tools takes a very important role in wind turbine blades manufacturing process.
What material is used for wind turbine blade?
Materials commonly used in wind turbine blades are described below.
Glass and carbon fibers
The stiffness of composites is determined by the stiffness of fibers and their volume content. Typically, E-glass fibers are used as main reinforcement in the composites. Typically, the glass/epoxy composites for wind turbine blades contain up to 75% glass by weight. This increases the stiffness, tensile and compression strength. A promising composite material is glass fiber with modified compositions like S-glass, R-glass etc. Other glass fibers developed by Owens Corning are ECRGLAS, Advantex and WindStrand.
Carbon fiber has more tensile strength, higher stiffness and lower density than glass fiber. An ideal candidate for these properties is the spar cap, a structural element of a blade which experiences high tensile loading. A 100-metre (330 ft) glass fiber blade could weigh up to 50 tonnes (110,000 lb), while using carbon fiber in the spar saves 20% to 30% weight, about 15 tonnes (33,000 lb). However, because carbon fiber is ten times more expensive, glass fiber is still dominant.
Hybrid reinforcements
Instead of making wind turbine blade reinforcements from pure glass or pure carbon, hybrid designs trade weight for cost. For example, for an 8-metre (26 ft) blade, a full replacement by carbon fiber would save 80% of weight but increase costs by 150%, while a 30% replacement would save 50% of weight and increase costs by 90%. Hybrid reinforcement materials include E-glass/carbon, E-glass/aramid. The current longest blade by LM Wind Power is made of carbon/glass hybrid composites. More research is needed about the optimal composition of materials
Nano-engineered polymers and composites
Additions of small amount (0.5 weight %) of nanoreinforcement (carbon nanotubes or nanoclay) in the polymer matrix of composites, fiber sizing or interlaminar layers can improve fatigue resistance, shear or compressive strength, and fracture toughness of the composites by 30% to 80%. Research has also shown that incorporating small amounts of carbon nanotubes (CNT) can increase the lifetime up to 1500%.
No matter of the material or shape of the blades, Electroplated Diamond Grinding Tool is the best choice for manufacturing wind turbine blades. Zhongbang supply the tailored solution for wind turbine blades manufacturer.
