Wind turbines techniques

Today the coin-tap test is a widely used technique on wind turbine rotor blades for inspection of thin GFRP laminates for disbonded and delaminated areas. However, since the sensitivity of this technique depends not only on the operator but also on the thickness of the inspected component, the coin-tap testing technique is most sensitive to defects positioned near the surface of the laminate. Therefore, there has been an increasing demand for alternative non-destmctive testing techniques which is less operator dependent and also more sensitive to delaminations and disbonded areas situated beyond thicker GFRP-laminates. 

Smith. G. M.. and Clayton. B. R. (1994). Thermography and other NDE techniques for wind turbine blades. Proc. of the Inspection Structural Composites Conf.. paper no. 7. 

Wind Turbine Components A common assembly technique is to lift the base tower from the transport vessel place it on the transition piece bolt it down and then lift, place, and bolt the next tower section on the previous tower section. Once the two to four tower sections are in place, the nacelle is lifted and secured to the top of the tower. The hub is lifted and bolted onto the nacelle if it is not already secured there, and then individual turbine blades are bolted onto the hub. In some instances, the hub with all three turbine blades is lifted and attached to the nacelle. This is referred to as a rotor lift. The process is repeated until all wind turbines of the wind farm are assembled. 

Abstract This chapter will discuss advances in the properties, production and manufacturing techniques of the advanced synthetic fibre/polymer composite materials that are utilised in the manufacture of machines that produce sustainable energy. Furthermore, it will suggest methods for the repair, maintenance and recycling of advanced polymer composite wind turbine blades. 

Composite materials/fabrication techniques for on-shore and off-shore wind turbines... 

Fabrication techniques for wind turbine blade moulds... 

Ghoshal A, Sundaresan MJ, Schulz Ml, Pai PF. Structural health monitoring techniques for wind turbine blades. J Wind Eng Ind Aerodyn 2000 85(3) 309—24. 

To illustrate the rapid increase in size of offshore wind turbine blades, LM Wind Power Group, Denmark, have recently developed a 73.5 metre blade manufactured in polymer composites which it was hoped would be installed at Alstom s prototype sites in Europe over the winter 2011-2012 the blades will travel at a speed of more than 320 km/h. A special prototype mould has been produced with a transparent surface that allows the full-scale manufacturing trials to be followed by visual inspection of the critical polyester infusion production (see Chapter 20, Section 20.4.2 for infusion techniques). When LM Wind Power began to produce wind turbine blades in 1978 the blades were 5 metres in length. 

Abstract This chapter will introduce advances in properties, production and manufacturing techniques of the advanced polymer/fibre composite materials that are utilised in the manufacture of machines that produce sustainable energy. Chapter 19 discussed the various methods of transferring wind, tidal, wave and solar energies into electrical power and this chapter will show how advanced composites are utilised in these various machines. Furthermore, it will suggest methods for the repair, maintenance and recycling of advanced polymer composite wind turbine blades. Finally, the future trends of sustainable energy systems and the role that polymers and polymer/fibre composites will have in their manufacture/fabrication will be evaluated. 

Fabrication techniques for the manufacture of the moulds for wind turbine blades... 

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