Indonesia is an agrarian country that continuously produces water, so it has the potential to develop a hydroelectric power plant. Computational Fluid Dynamic (CFD) application could be used to be an economical, quick, and efficient approach to improve the engineering design and turbine performance. This research aimed to find the effect of guide vane opening variations and total blades on cross-flow turbine performance using CFD simulation. This research used experimental modelling method with ANSYS program for turbine design with 22, 24, and 26 turbine blades and guide vane opening variations of 12°, 16°, 20°, 24°, and 36°. The data were collected by reviewing the simulation results after the numerical calculation process. The results showed that the cross-flow turbine performance was improving along with the increasing guide vane opening. The optimum turbine performance (power and efficiency) was obtained at 24° opening of guide vane and 26 total blades, producing 868.53 W power with 75.16% efficiency.

Shape memory alloys (SMAs) are metal alloys with a reversible ability to recover their shape at a certain temperature after being deformed. This ability referred to as Shape Memory Effect (SME). The application of SMAs such as Ni-Ti and Cu-Zn-Al alloys usually used on automotive, biomedical, etc. The commonly used SMA is Ni-Ti because of its superior SME properties than Cu-Zn-Al, even though the price is quite higher. The SME of Cu-Zn-Al might be improved by increasing the presence of the martensite phase in its microstructure by heat treatment. The heat treatment process given to Cu-21Zn-5Al alloy is a homogenizing, annealing, solution treatment process and quenched with brine solution and dry ice. The heat-treated alloys then undergo several examination trough hardness tests, X-Ray Diffraction, metallography, SME test, and Differential Scanning Calorimetry to determine the SME and microstructure of Cu-21Zn-5Al. From the test results, the specimen with temperature treatment solution of 850oC and quenched by brine solution had the highest SME value by 36.67%. All of the microstructure contained α, β, (martensite) and γ phases.

Nanoreinforce materials such as ZnO, eggshell, Al 2 O 3 , TiO 2 , and ZrO 2 have been shown to improve the mechanical properties of Al-Si alloy. Nanomaterial Fe 2 O 3 has many applications as catalysts reaction in electronic devices, for example, semiconductor materials, paint formulations, lithium rechargeable batteries, and is often applied in industrial fields. It is known that Fe 2 O 3 can be synthesized through the stirring process on machine and method used will involve several steps that relatively take a long time. In this study, Al-Si alloy reinforced by using nanomaterial Fe 2 O 3 which sintered at a temperature of 600°C for 3 hours aimed to improve mechanical and morphological properties of Al-Si alloy. The method used was stir casting, where this method was known as flexible, simple, and economic. The result of reinforcing Al-Si alloy by using nanomaterial Fe 2 O 3 had affected on the hardness level of Al-Si alloys as evidenced by the fracture morphology that was brittle and had a light reflection

Today‟s major challenge for oil industry is to improve the oil recovery from the reservoir. Various enhanced oil recovery (EOR) methods have been applied in the field and the steam injection is one of the most favourable methods. The deep reservoir will result in failure of this method due to excessive heat dissipation. In this situation, generating and injecting steam may be uneconomical due to the tremendous reduction of the recovery. Some methods using nanotechnology have been introduced and elaborated. However, we propose the electromagnetic (EM) method as an alternative due to its long range transmission of the transverse waves. These EM waves, coupled with some nanoparticles (NP), can modify the surface energy. We propose an optimum conditions based on some parameters namely, frequency, flux density, space charge density and skin depth, employing Maxwell and Helmholtz equations which interact with some magnetic and dielectric nanoparticles. A newly-designed EM antenna with a very high flux density is the model for this specific purpose. The electrical energy from the antenna transfers the waves to the dielectric and resistive nanoparticles, which is then transferred to the fluid with high capillary force. This results in lower surface tension which reduces the oil viscosity. In order to investigate the transport phenomena of the nanoparticles in porous medium, we applied Darcy‟s law. Our preliminary study for scale model simulations showed that at a frequency of 0.125Hz, the electric field of the curve antenna with magnetic feeders was 4280% higher compared to the one without magnetic feeders,At a frequency of 0.125Hz, the magnetic field of the curve antenna with magnetic feeders was 3677% higher in comparison with the one without magnetic feeders. With the increasing frequency from 0.125Hz to 9Hz, the electric field and magnetic field of the antenna with feeders decreased by 99%. The permeability and porosity of glass beads packed column was 30.58mD and 25.87% respectively. It was observed that the cumulative recovery of oil reached 21.11% by using ZnO nanofluid with electromagnetic waves, 17.23% by using ZnO nanofluid without electromagnetic waves, 32.59% by using iron oxide nanofluid with electromagnetic waves, and 29.68% by using iron oxide nanofluid without electromagnetic waves. In summary, the use of ZnO and iron oxide nanoparticles as nanofluids with electromagnetic waves is considered the most effective to use in enhanced oil recovery.

Ti42Zr40Ta3Si7.5Sn7.5metallic glass powder prepared for subsequent consolidation by hot pressing were produced by high energy ball milling from amorphous ribbon and both of the compositional and structural evolution on milled powders were studied using XRD and DSC analyses. By using WC vial and balls, the abrasion of milling media occurred causing WC contamination on < 105 µm milled powder after 2 cycles of milling. Based on DSC analysis, the contamination clearly reduced theΔTxof the alloy up to 48%. On the other hand, the contamination were overcome after milling using SS vial and balls, proved by no crystal peak observed on XRD pattern of all milling cycle levels. However, the thermal stability was noticed to be decreased implying the presence of nanocrystals on the amorphous powder after ball milling and the nanocrystal amount tend to be higher when more milling cycles were applied.