An approximate numerical mthod is presented for analysis and determination of modal characteristics in straight, pretwisted non-unifom helicopter blades. The analysis considers the coupled flapwise bending (out of plane), chordwise bending (in plane), and torsion vibration of both rotating and non-rotating blades. The proposed method is based on the integral expansion of Green functions (struct...

To simulate the forming process of a unidirectional (UD) glass fiber non-crimp fabric (NCF) for wind turbine blades, material needs to be characterized. In this way, input model simulation can generated. One important deformation characterize is out-of-plane bending. A number test setups have been described in literature but it not clear which setup more appropriate UD NCF under consideration. ...

Advanced high strength steels (AHSS) are engineered to have both high strength and enhanced formability characteristics. Yet, the formed components undergo springback due to elastic recovery after removal of the forming tools. This severely affects the dimensional accuracy of the part. Many techniques have been evolved to deal with springback. A simple approach is to design forming tools that c...

the research was conducted in order to determine the bending stress, young’s modulus, shearing stress, and shearing energy of safflower stalk as a function of moisture content and stalk region. the bending forces were measured at different moisture contents and the bending stress and the young’s modulus were calculated from these data. for measuring the shear forces, the stalk specimens were se...

one of the most prominent industries is bending, while using rotary draw bending method is known to be the most conventional approach for thin wall tube bending. pressure die is one effective tool which boosts the tube during the process and eventually improves the bending quality. other effective parameters are mandrel and the amount of clearance between tube and mandrel. in the present study,...

The surface-flattening process has many applications in industries such as shipbuilding. Curved surfaces the industry are usually formed from flat surfaces, so target surface needs to be flattened obtain its corresponding initial shape. In addition, flattening obtains inherent strain distribution required forming. Different forming methods plate will produce different membrane deformations, shr...

Much of the attention on simulation software in recent years has been focused on the modelling of bulk metal forming processes such as forging, rolling and extrusion. However, there are numerous applications for the simulation of sheet forming processes and indeed many pressings suppliers in the automotive industry are more advanced in the use of simulation than their forging counterparts. The ...

Abstract The use of advanced high-strength steels (AHSS) is associated with increased springback and represents a great challenge for today’s press shops regard to the dimensional accuracy cold-formed sheet metal parts. Springback, its appearance characteristics are mainly dependent on stress state introduced by forming process part geometry before opening tools. With aim determining influence ...