Stress distribution analysis for material and design optimization of 500 Watt wind turbine

Abstract

Wind turbine blade with capacity 500 Watt was chosen to be developed with consideration it is easy in making and installation so that it is suitable for use in remote areas. This blade is made with wood, fiberglass, and fibercarbon. To find out the performance and reliability of wind turbine blades, it is necessary to do prototype testing of wind turbine rotor blade aerofoil in wind tunnel. However, there are concern of damage to the prototype because the power of the aerofoil material is not yet known to withstand the maximum load arising from the velocity of the air flow. Therefore, to determine the maximum limit of air velocity, it is necessary to do a non-destructive study with a fluid dynamics simulation method based on Computational Fluid Dynamics (CFD). The simulation is focused on the blades of the wind turbine which are subjected to air flow (wind) with varying speeds. In this study numerical simulations of fluid dynamics is run around the turbine blades to obtain data on the distribution of forces and moments acting on the turbine blades, at various prices of wind speed. The results of the study resulted the value of the lift coefficient and the drag coefficient is relatively constant at all variations of speed. Large drag and lift forces on the blades increase with increasing wind speed. Likewise, the deflection moment increases with increasing wind speed. Drag force on the bar is greater than the lift force which means the deflection moment due to drag force is greater than the deflection moment due to the lift force. Pressure coefficient values vary along the blade with the maximum value in front of the blade surface and the minimum value behind the blade surface. The value obtained from the simulation combined with material testing then can be used as a reference value in wind tunnel testing.