No abstract

This paper describes a procedure for a simulation design aimed to achieve improved performance of the vehicle suspension, using magneto-rheological (MR) semi-active dampers. It is used a spatial so-called “Full car”-model of the vehicle. The model of the kinematic excitations from the unevenness of the road pavement is described in detail. The function of the MR damper is represented by linear and non-linear analytical models. Based on them, is obtained and its inverse neural-network model needed for the suspension control purposes.

No abstract

In this second part of the publication, numerical results for a specific a wind turbine model of a high class – prototype NREL 5MW are presented. A wind speed model is described, taking into account the vertical speed gradient and longitudinal turbulence. Based on the proposed by the authors a modification of Blade Element Momentum theory, the aerodynamic forces, distributed along the length of turbine blades, are calculated as time functions. As a result of this, according to the results of the first part of the publication, the dynamical loads, stresses, and deformations in the blades are calculated.

The wind turbines of a high class are with considerable sizes. For this reason, the consideration of the fluid field as a homogeneous when performing the aerodynamic analysis is not quite correct. In addition, due to the gusts and horizontal turbulence, the wind field is also nonstationary. All this causes dynamic, time-varying loads and fatigue. The determination of these loads is a major aim of this publication. The turbine blades are considered as Euler-Bernoulli beams under the impact of the aerodynamic thrust and torque forces as well as from this of the centrifugal force. The finite element method is applied to solve the partial differential equations describing the model under consideration. Two-node elements with four degrees of freedom for each node and a cubic, polynomial approximation of modal shapes were used. The deformations are relatively small in the separated finite elements and this makes it possible to apply the superposition principle.