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This paper presents a new design procedure for large wind turbine blades, which can be used in various case studies. The structural design of 2MW CFRP blade was performed using a verified 2MW GFRP blade model. The structural integrity assessment of the CFRP model demonstrated that the design criteria for tip deformation, buckling failure, and laminate failure in normal wind turbine operating conditions were met. The existing aero-elastic analysis code was not used to estimate the blade load, but the blade’s surface pressure was calculated using CFD. The conventional load analysis code necessitates the establishment of a turbine system and the input of structural characteristics with changes in the structural design specifications. However, when CFD was used to estimate the load, the turbine system was not required and the structure was evaluated against various design cases, making this a useful approach in preliminary design. This new structural design and evaluation procedure for wind blades can be used to review diverse design specifications in the initial design stage.

The final shape of fiber-reinforced polymer (FRP) materials is usually given by machining. However, machining FRP materials is complex and difficult. Appropriate cutting tools and cutting parameters should be determined to overcome these difficulties. In this work, glass fiber-reinforced polymer (GFRP) materials with 60% and 68% fiber ratio, produced by pultrusion method, were machined. End of the milling, surface roughness (Ra), delamination damage factor (Fdd), sound and vibration results were analyzed. Experiments were carried out with Taguchi L${}_{16}$ mixed design and the results were analyzed by Taguchi, ANOVA and Pareto charts. In Taguchi and Pareto analyses, the most effective parameter for surface roughness and delamination damage factor was the feed rate, and the cutting velocity for sound and vibration. Different regression models have been tried. Linear regression was found as most suitable. The significance values of the regression models are 92.04% for surface roughness, 87.12% for delamination damage factor, 98.64% for sound and 73.27% for vibration.

The drilling of glass fiber-reinforced plastic (GFRP) composites gained importance since they are used as structural components in many industries such as automotive, aerospace, and aviation. A large number of holes are needed in the industry to join these composite parts. However, some failures occur in drilling GFRP composites, such as delamination, matrix cracking, and fiber breakage. These failures not only reduce the strength of the composite, but also reduce its service life. Drilling parameters, drill bits, and woven types have a great influence on the occurrence of these failures by greatly influencing the thrust force, surface quality, and cutting temperature. In this study, the effects of drilling parameters and woven types of GFRP composites on thrust force, surface roughness, delamination factor, and cutting temperature were examined in the drilling of uni-directional (UD), $\pm 45^{\circ }$ and 0${}^{\circ }∕90^{\circ }$ GFRP woven composites. The effects of drilling parameters and the delamination factor on the tensile strength of the drilled specimen were also investigated. The result of this study indicated that thrust force, delamination factor, and surface roughness increased with increasing cutting speed and feed rate. An increase in feed rate decreased the cutting temperature, while an increase in cutting speed increased the cutting temperature. Also, it was found that the delamination factor had a critical influence on the tensile strength of the GFRP composites.

In manufacturing industries, polymers are widely used due to their exceptional physiochemical and mechanical characteristics. It consists of high strength, low weight, corrosive resistivity, and ease of fabrication. Glass fiber is more cost-effective and easily available than other fibers such as carbon, aramid and kevlar. The most challenging issue for the manufacturer in the laminated polymer is the non-homogeneity and anisotropic behavior. This nature also hinders the machining performance of laminated polymer composites, which are entirely different from metals and their alloys. The supplements of nanomaterials enhanced the physiomechanical properties and the machining efficiency of fiber laminates. This work highlights the machining (drilling) aspect of glass fiber-reinforced polymer composites modified by multiwall carbon nanotube (MWCNT). The effect of drilling factors such as spindle speed ($S$), feed rate ($F$), and MWCNT weight percent (wt.%) on machining responses such as Thrust force (Th), Torque ($T$), and Surface roughness (SR) has been investigated. The drilling operations were conducted using the 5 mm diameter TiAN (Sic coated) according to the response surface methodology (RSM) design. The process constraints were controlled by the hybrid module of additive ratio assessment (ARAS) and the Artificial Bee Colony (ABC) algorithm. The nature-inspired principles of the bee are used to optimize the objective function. The multiple responses were aggregated using the ARAS method, and its objective function is fed into the ABC algorithm. It was remarked that the hybrid ARAS-ABC is more capable than the traditional ARAS, with an overall improvement of 7.33% in assessment values. The scanning electron microscopy (SEM) test confirms the feasibility of the proposed hybrid (ARAS-ABC) module to achieve a favorable machining environment while drilling modified nanocomposites.

The paper focuses on the cutting behavior of Glass Fiber Reinforced Polymer (GFRP) composites and GNP–GFRP composites that contain varying amounts of Graphene Nano Platelets (GNP). GFRP composites are increasingly being used in a variety of industrial applications due to their excellent mechanical properties, such as high strength, stiffness, and low weight. However, their machining and cutting behavior can be challenging due to the presence of the reinforcing fibers. Therefore, the study aims to investigate the machining behavior of GFRP composites and the effect of adding GNP on their cutting behavior. The effect of different parameters such as cutting speed, feed rate and reinforcement rate on cutting forces and delamination factor is investigated. In addition, the tensile strength and fatigue behavior of the composite materials with the best and worst delamination factors were also determined. Addition of up to 0.2 wt.% of GNP to GFRP composites resulted in an increase in cutting forces and delamination factor when drilling GFRP composites. While the cutting force and delamination factor decreased with the increase in cutting speed, the cutting force and delamination factor increased with the increase in the feed rate. Analysis of variance (ANOVA) was performed to determine the effects of drilling parameters and reinforcement ratio on cutting force and delamination factor according to full factorial experimental design. The most efficient factor on the cutting forces is found to be feed rate (84.97%), followed by the reinforced rate (6.48%) and cutting speed (6.13%). The most efficient factor on the delamination factor is determined to be feed rate for (44.49%), followed by the reinforced rate (29.20%) and cutting speed (21.73%).

In recent years, fiber-reinforced plastics (FRPs) materials like glass fiber-reinforced plastic (GFRP) and carbon fiber-reinforced plastic (CFRP) are next-generation polymer-based composite materials tailored for lightweight engineering applications in aerospace, marine, chemical, and automotive industries. Applying inclined holes in GFRP material is essentially used in producing robotic parts, microelectronics components, wind turbine blades, etc. The bending actuators and microhinges of microrobots constructed from CFRP materials also require inclined holes. Laser percussion drilling techniques produce a high aspect ratio of high-resolution inclined holes. The geometrical deviation of the laser-drilled hole is usually evaluated in terms of hole circularity and hole taper. No literature is available for inclined hole drilling of the above two types of FRPs using infrared (IR) laser. In this paper, the thickness of each FRP is taken as 1, 3 and 5mm, respectively. The one-parameter-at-a-time (OPAT) method was used to analyze the individual effects of laser input parameters, such as pulse current, pulse width, assist gas pressure, workpiece thickness, and incidence angle, on output performance characteristics of hole circularity at top (THC), bottom (BHC), and taper (TH) during laser percussion-inclined drilling with millisecond (ms) pulsed Nd: YAG. Pulse current of 200–225A or 275–300A does not affect THC at a zero-degree angle of incidence. A greater pulse current (300A) is produced during inclined drilling at 100^∘ and 200^∘. SEM/EDX investigation reveals hole surface and material composition.

Under the background of the truss bridge in Gaoliang ship lock across Huaihe river, which is made of glass fiber reinforced polymer (GFRP) profiles, APDL language based on ANSYS is used to organize corresponding command stream program and built 3D finite element model. According to the actual situation of the bridge, the static analysis and modal analysis of the truss bridge to test the static and dynamic performance is conducted. The mechanical property when the bridge material was replaced with BFRP and CFRP is analyzed.