The numerical simulation of the post-weld shot peening (SP) process was performed to analyze the influence of various SP parameters on the final induced compressive residual stress (CRS). Firstly, the welding process was simulated based on the Finite Element Method (FEM) using ABAQUS CAE and FORTRAN user subroutine code, from which the initial welding-induced tensile residual stresses (TRS) were obtained. The FE model was validated using the results obtained from the TIG welding of the aluminum 2219 alloy (AA 2219) plate. Then, the post-weld SP process was numerically simulated using the combined discrete and finite element methods (DEM-FEM). The computed CRS from the simulation was compared with the experimentally measured outcome to validate the DEM-FEM model, and good agreement was observed from the compared results. Finally, the post-weld SP model was applied to extensively analyze the influence of the various SP parameters related to the peening media and target material on the final CRS.

No abstract

A numerical investigation of the deflection on blades of three different materials against the range of wind speeds, and the effect on the blades’ aerodynamic performance was carried out. ABS plastic, wood and glass fiber were used to make blade solid models with Eppler E387 airfoil. Using ANSYS software, wind load impact simulation was carried on the blades over range of operation wind speeds to determine blade tip deflections. Highest and lowest deflection over the range of wind speeds were found to be for ABS plastic blade and glass fibre blade respectively Deflected blades were adopted to a commercial 20 kW wind turbine as a case study. The turbines were subjected to air flow simulation to determine aerodynamic performances over the range of 5m/s to 20m/s wind speeds. At rated wind speed of 10m/s, power coefficient values of 0.52175, 0.53685 and 0.53710 at optimum tip speed ratio (TSR) of 5 were produced by ABS, wood and glass fibre blades respectively. At severe wind speed of 20m/s, corresponding power coefficient values were 0.29911, 0.47458 and 0.58666 respectively. The study indicates that at normal operating winds speeds, all the materials are suitable for blade adoption, while glass fibre material seems to withstand severe wind speed most in aerodynamic performance.