This paper presents a method for stochastic deterioration modeling and fatigue damage assessment composite wind turbine blades operating in offshore environments. The of the is analyzed assessed based on estimates applied loads along blade span, stress analysis, crack evolution, lifetime probability failure. complex states are mainly caused by aerodynamic generated corrected element momentum th...

This work presents a Boundary Element Method (BEM) formulation for contactless electromagnetic field assessments. The new scheme is based on a regularized BEM approach that requires the use of electric measurements only. The regularization is obtained by leveraging on an extension of Calderon techniques to rectangular systems leading to well-conditioned problems independent of the discretizatio...

We present an optimization-based synthesis algorithm for the design of diffractive optical elements (DOE’s) that are finite in extent, have subwavelength features, and are aperiodic. The subwavelength nature of the DOE’s precludes the use of scalar diffraction theory, and their finite extent and aperiodic nature prevents the use of coupled-wave analysis. To overcome these limitations, we apply ...

In this paper it is attempted to investigate the behavior of an inviscid flow in the meridional plane of an axial flow compressor. For this purpose the 3-D unsteady Euler equations in cylindrical coordinate are averaged in tangential direction. Therefore, the equations are reduced to a 2-D system. By averaging the tangential component of momentum equation, a blade force will result. Axial and r...

In this using paper a method is presented for the aerodynamic and structural analysis of a horizontal axis wind turbine using simplified methods. In the first part of the program the optimum rotor configuration for twist and chord is determined using the momentum and blade element theories for a rotor without coning or tilting and assuming zero drag average wind velocity. Then coning angle and ...

As for a ship oscillating at free surface with frequency that ranges from those that are common for ship motion in waves to very high frequency associating with the impact problem, the vertical force acting on the ship for the lower limit of frequency range is dominated by gravity effect, which is usually ignored in the impact theory. As a consequence there must be a transition range in between...

In this work, possibility of simulating biological organs in realtime using the Boundary Element Method (BEM) is investigated. Biological organs are assumed to follow linear elastostatic material behavior, and constant boundary element is the element type used. First, a Graphics Processing Unit (GPU) is used to speed up the BEM computations to achieve the realtime performance. Next, instead of ...

The Time-Domain Boundary Element Method (TDBEM) is a well known numerical technique that handles quite properly dynamic analyses considering infinite dimension media. However, when these analyses are also related to nonlinear behavior, very complex numerical procedures arise considering the TD-BEM, which may turn its application prohibitive. In order to avoid this drawback and model nonlinear i...

During forward flight, the flow field of autorotating rotor was very complicated, which caused induced velocity disc plane difficult to be obtained. In order analyze aerodynamic characteristics rotor, improved blade element theory, using unlimited-bladed fixed wake method establish a mathematical model, could obtain by rotor. According Biot-Savert Theorem, expression axial got integerating. The...

About a century ago, two different rotor models were proposed by Joukowsky (1912–1918) and Betz (1919). Both based on assumptions regarding the vortex structures of wake its induction plane. However, due to complications formulating behavior into actual guidelines for aerodynamic design geometry, have until now not been used industrial wind turbine rotors. In this article, we propose technique ...