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.

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.

One way to reduce maintenance costs while improving wind turbine efficiency is to replace mechanical bearings with permanent magnetic bearings. The permanent magnetic bearing is a free contact bearing in which the rotor is elevated from the stator by the magnet's repelling force. The purpose of this study is to analyze the variation of permanent magnet width and the gap distance between the rotor-stator magnets that can produce the magnetic axial force opposing the thrust force of 1MW horizontal axis wind turbines (HAWT). The method used in this study is a magnetic force simulation using finite element method by varying the magnet thickness, width of the gap, and displacement between the rotor-stator of the PMB model. The PMB model consists of rotor and stator magnets arranged in 3 layers with Nd2Fe14B type material with a magnetic flux density of 1.45 T. Variations in thickness of the rotor and stator magnets are 0.1; 0.15, respectively; 0.2 (m), while variations in the width of the magnetic gap are 4, 5, 6 (mm). The results of the study found that the displacement that produces an axial magnetic force that can support a thrust force of 199.5kN is the lowest in the PMB model with a magnetic thickness of 0.15m with a magnetic gap of 4mm, while the highest is at a magnetic thickness of 0.1m with a magnet gap of 6mm. The greater the thickness of the PMB axial magnet design, the greater the displacement that provides zero axial magnetic forces. Further, the maximum of the magnetic axial force is rise on with increasing magnet thickness.

Biomass Gasification is an attractive renewable energy technology. Biomass waste, as well as a renewable energy source and also, could be used as raw material to produce syngas. Nevertheless, the biomass is containing tar. The downdraft gasifier is considered to produce less tar, however, the syngas still containing tar which makes blocking and fouling of engines. Therefore, reducing tar is needed, one of them using a wet scrubber that is technically and economically viable to obtain clean syngas. Wet scrubber using absorbent to make absorption. This paper investigated the effect of variations on the type of absorbent in the scrubber to reduce tar in syngas. The absorbent used is vegetable glycerine food grade as a solvent and coconut shell charcoal with a mesh of 10-20 as a packing material. There are two variations of absorbent. Firstly, using only vegetable glycerine food grade and the second using vegetable glycerine food grade and coconut shell charcoal. Each variation was given a vegetable glycerine food-grade discharge of 31.5 ml/s. The results showed that variations in the absorbent of vegetable glycerine food grade and coconut shell charcoal resulted in higher tar removal rates is 100% in Acids, 51.88% in Furans, 65.04% in Alcohols, 35.12% in Ketones.

The strategy of design engineering is very important to produce the modernization of technology. The propeller is one of crucial part in the marine design especially for the marine transportation especially for traditional fishing vessel. In this paper, presents a study for analysis of the propeller performance by using numerical simulation in the computational fluid dynamics (CFD). Since the development of CFD simulation, still facing several problems to solve the CFD analysis. The OpenFOAM is open source CFD tool used in this study in order to investigate the propeller performances. OpenFOAM is implemented for open water performances of KCS propeller (KP505). Reynold-averaged Navier Stokes equations (RANS) was applied to estimate the turbulence of K-w SST model. Unstructured mesh in this simulation was employing a hexahedral mesh as mesh generation. The multiple rotating frame (MRF) was produced as method to analysis of propeller performances. The velocity inlet and pressure outlet were put for inflow and outflow boundaries. The wall was set to a far-field boundary. The current study compared to the experimental result for the thrust and torque coefficient to validate the propeller performances. By using MRF technique, the simulation of interaction for the propeller with a relative error less than 2%. Thus, The MRF technique can be used for the practical technique to simulate the ship propeller model especially for the moving multiple zones.

The rotor power of HAWT can be affected by the type of airfoil and airfoil modifications on a blade. However, no study of wind turbine blades from arranges types of airfoils or altering the leading and trailing edges has been conducted. To determine the maximum torque, TSR, power, and power coefficient values at Horizontal Axis Wind Turbine (HAWT) 1MW, simulations of turbine blades with various airfoil designs are performed. NACA 4412 and 2412 airfoils were utilized, with the leading and trailing edges modified. The method used is Blade Element Momentum simulation on 20 blade variations with modified NACA airfoils. The HAWT simulation parameters use the specifications of a 1MW wind turbine with a blade radius of 54m, wind speed of 7 m/s, number of blades 3. Due to the aerodynamic simulation results, the percentage error between the CFD from the other study and the BEM values is only 2.6%. The blade code that produces high torque on the HAWT is 4T-4LT (4412 TE mod-4412 LE-TE mod). The high torque value is influenced by the lift and drag coefficients. High torque does not usually imply high power; rather, the TSR as a function of angular speed determines this. The angular speed of a horizontal axis wind turbine is visibly affected by the aerodynamics of the rotor blade. C4412-2412 group combination blade designs, particularly blade codes 4L-2LT, 4T-2LT, 4LT-2L, 4LT-2T, and 4LT-2LT, can produce more than 1MW. The highest TSR, power, and coefficient power of HAWT was obtained from blades with circular foil segments 1 and 2, segments 3 to 9 using NACA 4412 LE-TE mod airfoil, and segments 10 to 11 using NACA 2412 LE-TE airfoil. Although the difference is slight (0.20%), the combination of modified trailing and leading edge NACA 4412 and 2412 airfoils outperforms modified leading edge airfoils alone.