Spar

About: Spar is a research topic. Over the lifetime, 1476 publications have been published within this topic receiving 12931 citations.

Wind turbine blade

Abstract: A wind-turbine blade that prevents foreign matter from entering the inside thereof during transportation and that can be efficiently assembled in good condition is provided. A wind-turbine blade includes a skin that forms a long and hollow shape, and a main spar that extends in the longitudinal direction and reinforces the skin from the inside thereof. The main spar is divided into a blade-root-side main spar and a blade-tip-side main spar in the longitudinal direction; the blade-root-side main spar and the blade-tip-side main spar have connection sections that are connected to each other; the skin is divided into a connection-section skin, located at a position corresponding to the connection sections, a blade-root-side skin, and a blade-tip-side skin; and openings formed in the blade-root-side skin and the blade-tip-side skin are blocked off by blanking plates.

Hull/Mooring Coupled Dynamic Analysis of a Truss Spar In Time Domain

Abstract: Nonlinear coupled dynamic analysis of a moored truss spar in waves with collinear winds and currents is numerically carried out in the time domain and the results are compared with 1:61 scale experiments and uncoupled analyses. The first- and second-order wave forces, added mass and radiation damping, and wave drift damping are calculated from the hydrodynamics program WINTCOL. The total wave force time series are then generated based on a two-term Volterra series model. The mooring dynamics are solved using the software WINPOST which is based on a generalized-coordinate-based finite element method. The mooring lines are coupled to the platform through generalized springs and dampers. A case study was conducted for the Marlin truss spar with nine taut mooring lines in 3240-ft water depth. The numerical results show that dynamic effects are very important for the present mooring design. The motion and tension spectra of uncoupled analyses with linear spring or nonlinear spring are also compared with those obtained from fully coupled analysis to assess the importance of hull/mooring coupling.

Composite spar structure having integral fitting for rotational hub mounting

Abstract: Hollow filament wound spar structure is provided adapted for rotational hub mounting under centrifugal and bending loads. The structure comprises an integrally wound, filament and resin composite spar of a predetermined wall thickness, a fitting integrally wound therein, the fitting defining rotational hub fastening means and comprising a plug having a mechanical engagement groove circumferentially of its longitudinal axis into which the opposing spar wall portion is deflected responsive to winding fabrication of the spar wall on the fitting. Belt means additionally are provided opposite the groove locally peripherally confining the deflected spar wall portion in mechanical engagement reinforcing relation, against relative dislodgement of the spar wall portion from the plug groove in the mounted condition of the spar structure, under centrifugal and bending loads.