Engineering Headway Vol. 20

Abstract: Fluid is a substance that can flow and conform to its container. Any substance or material that experiences movement or moves from one place to another will produce energy and this energy is strongly influenced by the physical properties of the fluid which is the source of this energy. Because of the same fluid properties, Savonius can also be applied to water flows. The Savonius waterwheel is a simple water-wheel that works because of the different forces on each blade. The concave blade (concave) facing the direction of the water will catch the water and force the blade to rotate on its axis and the convex blade (convex) which is pushed by the fluid flow also causes the blade to rotate even though there is a load caused by the convex part when pushed by the flow. This study determines to analyze efficiency and power of vertical shaft savonius water wheel with four blades and six blades on discharge variations. The best performance of the vertical shaft savonius water wheel with four blades is on load of 1.5 kg, the highest efficiency 17.16% and the highest water wheel power 1.317 watts with discharge of 0.629 m³/s. For the best performance of the vertical shaft savonius waterwheel with six blades on discharge 1 (0.629 m³/s) produced the highest power of 1.248 watt and the highest efficiency 15.92% at load of 1.5 kg.

Abstract: Indonesia is a country prone to hydrological disasters, with high potentials to mud flows in some areas. The mud flows need to be channeled to the appropriate place, and the piping system is one of the best alternatives. Through this research, the analysis of flow characteristics and changes in the density concentration in two-phase (liquid-solid) fluid systems is presented. One-inch diameter transparent PVC pipe was used as the test pipe. The pressure drop, experimental friction factor, and Reynolds number on the experimental variables show an interesting relation between the variables. At 10% ratio of liquid-solid discharge, the flow discharge ranges from 0.00000800 m³/s to 0.00001817 m³/s, while at 100% ratio, the discharge reaches 0.00002133 m³/s. The ratios of liquid-solid discharge ratio of 10% to 100% have influences on increasing pressure reduction (∆P). At increasing density from 1000 to 1010 (at mixture ratios of 10% to 20%), the pressure drop (∆P) also tends to increase. At 10%, the f value ranges from 0.0005004 to 0.0011364, where the experimental friction factor tends to be lower than the theoretical friction factor.

Abstract: High voltage overhead transmission line is a transmission tower used to conduct electricity with a voltage of 35 kV to 230 kV. In the installation of the HV overhead transmission line tower structure, one of the main things that need to be considered is the installation of stub that can affect the sturdiness of the tower. This research aims to design and make a stub setting fixture on the HV overhead transmission tower installation. The research process began with data observation and literature study of tower stub installation in the 150kV 2xZebra Andolo – Kasipute Sec.1 installation project of PT. PLN Persero UIP South Sulawesi, then designed the stub setting fixture components, design data analysis, and fixture manufacturing. The results of the analysis of the design structure experienced do not exceed the limits of the material stresses of the component, the analysis of machine elements in the stub setting fixture is able to withstand the loads experienced by the component. It is expected that there will be improvements and development of fixture in the form of more efficient forms of construction and operation, and can use analog and digital controls in terms of fixture operation in subsequent development and research.

Abstract: The forecast for electrical energy demands in the South Sulawesi area in 2060 is 198,353 GWh, so the electricity generation capacity required under the Business As Usual scenario is 38.68 GW in that year. If this demand is connected to the scenario of limiting the construction and operation of coal-fired power plants, then the capacity required is 41.02 GW. This article provides an overview of the value of electrical energy demand and generating capacity in South Sulawesi where the method used to plan additional electricity generating capacity is based on the OSeMOSYS model. The generating capacity of the analysis results comes from various types of power plants, namely: conventional types (combine cycle power plant, gas turbine power plant, gas engine power plant, coal-fired power plant, and diesel power plant), and Renewable Energy types (hydropower plant, mini hydro power plant, biomass power plant, waste-to-energy power plant, geothermal power plant, wind turbine power plant, and photovoltaic power plant). The primary energy used by these power plants comes from the South Sulawesi area and from outside South Sulawesi. Specifically, renewable energy is the potential of the South Sulawesi region.

Abstract: The 150 kV High Voltage Overhead Line or what is called SUTT-150kV as a distributor of electrical energy from one substation to another substation often experiences disruption due to lightning. This interference will reduce the reliability of the SUTT-150kV. Handling the consequences of lightning is very necessary to protect SUTT-150kV. The magnitude of the electric current from lightning striking a SUTT-150kV can exceed 100 kA. Evaluation of the protection performance of SUTT-150kV is very necessary. This research models a SUTT-150kV in the context of analyzing the protection of the line from the impact of lightning strikes using ATPDraw software. SUTT-150kV is modeled in several parts into: line (ground wire and phase conductor), crossarm, tower, tower surge impedance, string insulator, and tower ground resistance. So, the discussion in this paper is about the influence of the grounding resistance value of a transmission tower with the same lightning strike on each ground wire. When the electric current from lightning strikes the ground wire, the effect of the lightning strike can be seen on the phase conductors, both the top and bottom phase conductors. The induced voltage on the transmission tower can be reduced by reducing the tower's grounding resistance value.