Rain erosion induced by raindrops impacting wind turbine blades at high velocity can change the aerodynamic characteristics of the blades and increase maintenance costs. Previous numerical studies on rain erosion have not considered the curvature of the blade leading-edge surfaces and assumed them to be flat surfaces. This study established a fluid-solid coupled numerical model combining the finite element method and smooth particle hydrodynamics. It models a water droplet with a diameter of 2.74 mm impacting the curved leading-edge surface of wind turbine blades with radii of curvature of 1.35 mm, 6.75 mm, 67.5 mm, and infinite at 110 m/s, and the effects of the radius of curvature on the impact response were analyzed. The results show that as the radius of curvature of the leading-edge surface increases, the surface obstructs the water droplet more significantly, and the lateral jetting of the water droplet is enhanced. A larger radius of curvature causes more droplet impact energy to be transferred to the curved surface, increasing the contact force between the water droplet and the surface. The increased transferred impact energy results in higher stress and plastic strain values. The decrease in the radius of curvature of a curved surface increases the error in the stress and strain results obtained by assuming it to be a flat surface.

Using numerical simulation methods, the thermal-fluid-solid bidirectional coupling analysis was conducted on the opening process of a certain hydraulic valve at different speeds. The distribution patterns of pressure and temperature in the flow field were analyzed. Based on this, the deformation of the valve body and valve spool, as well as the axial force on the valve spool, were analyzed. The results indicate that when the opening speed is low, the eddy current area inside the valve chamber is small and the intensity is low, leading to a more stable pressure distribution. The opening speed of the valve spool affects the rate of temperature rise inside the valve chamber, while the deformation of the valve body and valve spool gradually increases. The variation in the valve spool speed has a minor effect on the deformation of the valve body and valve spool. The axial force on the valve spool manifests as resistance, initially increasing, stabilizing for a period, and then gradually decreasing.