This paper presents flexural and tensile properties of sugar palm (Arenga pinnata) fibres-reinforced polyester composites study. The fibres were treated by alkaline solution with 5% NaOH solution for 2 hours of soaking time. The composites were prepared with different orientations of fibres (i.e. 0° + 45°, 0° + 90°, 45° + 90°, and 45° + (-45°)), while the ratio between Arenga pinnata fibres and polyester is 30 percent volume. Hand lay-up method was employed to produce the specimens. ASTM D-790 03 and ASTM D-3039 standard were employed to characterize the specimens in good sequent. As the result, the specimen with 45°+90° orientation generated maximum important values both in flexural strength (24.03 MPa) and modulus (4.01 GPa), tensile strength (23.84 MPa) and modulus elasticity (0.97 GPa). This is due to palm fibres as reinforcement that forms an angle of 90 ° or increasingly upright to the load crossing field (load of bending) and tensile load giving the effect of maximum reinforcement compared to other fibres orientations.

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This paper presents rotor power optimization of the Horizontal Axis Wind Turbine of various parameters such as airfoil, angle of attack, and wind speed. Simulation of HAWT rotor power uses Blade Element Momentum (BEM). Furthermore, optimization using the Taguchi method with L16(43) orthogonal array. The parameters used in this study were: airfoil NACA (National Advisory Committee for Aeronautics) 4412, NACA 2412, NACA 4412-NACA 2412, NACA 4412mod-NACA 2412mod; angle of attack 3˚, 4˚, 5˚, 6˚; and wind speed of 5, 6, 7, 8 (m/s). The simulation uses the general parameter at 1 MW HAWT. Several types of NACA airfoil, angle of attack, and wind speed were simulated, then optimized to obtain optimal parameters for the HAWT output power. The results of this study found the most optimal rotor power, namely the condition of the NACA 4412mod-NACA 2412mod airfoil, 3˚ angle of attack, and 8m/s wind speed. Wind speed is the most significant influence factor based on ANOVA analysis ranked 1st based on S/N ratio analysis, 2nd rank is an airfoil, and 3rd rank is the angle of attack. The higher the wind speed, the greater the rotor power generated.

Purpose – In this study, the hybrid Taguchi genetic algorithm (HTGA) was used to optimize the computer numerical control-printed circuit boards drilling path. The optimization was performed by searching for the shortest route for the drilling path. The number of feasible solutions is exponentially related to the number of hole positions. The paper aims to discuss these issues. Design/methodology/approach – Therefore, a traveling cutting tool problem (TCP), which is similar to the traveling salesman problem, was used to evaluate the drilling path; this evaluation is considered an NP-hard problem. In this paper, an improved genetic algorithm embedded in the Taguchi method and a neighbor search method are proposed for improving the solution quality. The classical TCP problems proposed by Lim et al. (2014) were used for validating the performance of the proposed algorithm. Findings – Results showed that the proposed algorithm outperforms a previous study in robustness and convergence speed. Originality/value – The HTGA has not been used for optimizing the drilling path. This study shows that the HTGA can be applied to complex problems.

The rotor is one of the vital components of a wind turbine. In the design of the rotor, the expected result is the most optimal power. This purpose study is to optimization of the Horizontal Axis Wind Turbine power of various parameters such as airfoil, angle of attack, and pitch angle. Airfoils (NACA 4412-2412 T.E. mod, NACA 2412-4412 T.E. mod, NACA 4412-2412 L.E. mod, NACA 2412-4412 L.E. mod), angle of attack (0, 2, 4, 6), and pitch angle (0, 1, 2, 3) are the parameter variations used. The simulation method uses BEM (Blade Element Momentum), and the Taguchi for optimization is based on the L16 orthogonal array matrix. The ANOVA has to determine the contribution of each parameter to the HAWT power generated. Simulation and optimization results show that the most optimal parameter was a NACA airfoil 4412-2412 L.E mod, at 0˚ angle of attack and 0˚ pitch angle, with the resulting power reaching 1015780 Watt. The ANOVA analysis shows the airfoil parameter has the greatest contribution to the rotor power of the HAWT compared to the angle of attack and pitch angle.

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To improve electrical energy better, the design and optimization of micro scale wind turbines has become a very important element in research. The aims are improving the ability to capture power and maximize energy production properly. The object of this study was horizontal axis wind turbine performance testing with the configuration of types and numbers of NACA 3612 blade variation in terms of output power (W), efficiency (η) and tip speed ratio (TSR). The tests carried out in the laboratory using a wind tunnel. There are 8 variations of wind speed, 1.41 m/s, 1.76 m/s, 2.51 m/s, 3.74 m/s, 4.81 m/s, 5.50 m/s, 5.71 m/s and 6.11 m/s. The results showed that the best power value was a taperless type with 2 blades of 0.846 watts with a maximum rotating speed of 876.3 rpm at 6.11 m/s wind speed. For the best efficiency value obtained at 3.74 m/s wind speed on the type of taper with a number of 4 blades of 2.9% at TSR 4.778. While the maximum TSR occurs in the type of taper with a number of 3 blades of 6.256 at 3.74 m/s wind speed by testing without using a prony brake.

This study aims are to analyze stress and displacement using Finite Element Method (FEM) of the three components design of powder packaging machine. The safety factor (SF) is calculated to compare with the design acceptance criteria, more than two. The frame is made of ASTM A36 steel angle bar, while the camshaft and sealer sleeve of AISI 1018. Steel angle bar widths of 40x40 (mm) and 50x50 (mm) with a thickness of 3,4,5 (mm) use for the frame design variant. The diameters of the camshaft design variants are 0.75”, 1”, and 1.25”. Then, the sealer sleeve variant utilizes thicknesses of 10, 12, and 14 (mm). Loading assumption during adverse operating conditions, such as when there is an obstacle or jam. Through the finite element method results, increasing the thickness of the frame also the sealer sleeve, and increasing the diameter of the camshaft, produced a decrease in the value of von mises stress and displacement. The safety factor for all variants of frame thickness was more than two, indicating that all designs were safe and acceptable. Nevertheless, there is one design failure on the camshaft and sealer sleeve because the SF value is less than two.