Kajian Numerik Penerapan Push-Pull Ventilation dengan Rasio Kecepatan 6 dan 8 untuk Melindungi Pekerja Pabrik dari Penularan Covid-19

Abstract - The transmission of COVID-19 is still spreading in the world, including in Indonesia. The increasing number of positive cases of COVID-19 in Indonesia, one of the causes is transmission from industrial clusters. Keeping a minimum distance of 1 to 2 meters between workers is difficult to implement. This is due to the limitations of layout, area, and work systems in the industry. Therefore, a system is needed to protect industrial workers from potential exposure to COVID-19. One of the technologies that has a high potential to be applied is the air-curtain. In this analyzes the push-pull air curtain where there is push-pull ventilation that is able to protect workers from microdroplet inhalation. The extent to which push-pull ventilation is able to withstand droplet bursts using push-pull ventilation velocity ratios of 8 and 6. To be able to find out this, a simulation was carried out with Salome s, OpenFOAM, ParaView software. The results of the simulation carried out that the velocity ratio of 8 can withstand droplet bursts, having a percentage of droplets that penetrate 22.7 percent. Meanwhile, the ratio of 6 has a percentage value of droplets that penetrates 6.38 percen

Analisis Kinerja Perpindahan Panas Fluida Perantara untuk Intermediate Fluid Vaporizer pada Sistem Regasifikasi Gas Alam Cair

Abstract - PLTGU fuel was originally from high-speed diesel fuel to LNG. For this reason, a regasification system is needed to support this process. For this reason, a regasification terminal is needed to facilitate the process. In procuring a small-scale floating Liquified Natural Gas (LNG) regasification terminal, a regasification tool with a relatively small size but good performance is required. Intermediate Fluid Vaporizer (IFV) as a regasification tool is very suitable to be used because when compared to other types of regasification equipment, IFV has the simplest structure and shape and relatively small size, as well as its performance, is quite good in the regasification process. IFV uses an intermediate fluid for the LNG evaporation process to the gas phase. The type of medium fluid that is widely used in IFV today is Propane. However, the use of Propane still has several risks, one of which is fire. With these problems, research was made to replace Propane with a more adequate fluid. The analysis was carried out using the Aspen Hysys  software to get the working pressure, then for the numerical simulation using the OpenFoam software. The selected fluid must have good heat transfer performance. From the results of the study, it can be concluded that overall both from the value of heat transfer area, heat transfer coefficient, working pressure, and in terms of environmental friendliness, the intermediary fluid substitute for propane has the highest value according to the Intermediate Fluid Scoring is R-500. R-500 is suitable to replace propane as an intermediate fluid

Simulasi Laju Perpindahan Panas Serrated Finned Tube pada Heat Exchanger dengan Menggunakan Kondisi Batas Periodik

Heat exchanger is a tool that use for exchange the heat to be cool and heat the fluid. Heat exchanger is widely used for air conditioning, chemical processing, and power plants by using coal, natural gas, etc as fuel. Greater heat exchanger capacity needs greater fuel requirements used, it is necessary to design optimization in the heat exchanger. Using fin in the heat exchanger tube is one way to increase the heat transfer rate because of increases the surface area. From previous research, serrated fin is one type of fin with high efficiency because it can increase the value of fluid turbulence. The aim of this research is to know the  heat transfer rate that occurs in serrated finned tube, assumed that each side is periodic boundry condition. The result shows that periodic boundry condition can be apply for serrated finned tube in heat exchanger simulation, with error between this study and previous study by Martinez (2015)  is less than 5%

Re Design Filtering Water Cleaning Piping System On Food And Beverage Industries

Abstract - The water treatment piping system functions to carry out a filtering water process which aims to provide clean water quality before being used in the production, utilization, and domestic processes of food and beverage industry. There are two filter tanks, namely sand filters and carbon filters. Sand filter tanks are water filtration media that use sand and other granular media (such as gravel or anthracite) to remove impurities in water. Carbon filter tanks are water filtration media that use activated carbon to remove contaminants and dirt. Analysis method is starting by calculating the minimum wall thickness (Tm), flow rate (Q), head losses (HL), and pump efficiency to determine the optimal design in the water filtering process. As well as an analysis with the Pipe Flow Expert (PFE) in each design with variations made to determine the design optimization. And project management plan analysis is done to find out the scheduling and duration of the project. The results of this research it is known the most optimal design is design 3 with a variation of NPS 2 inch pipe diameter using Ebara 50x40 FS2HA pump (Company requirement). It is known that the minimum wall thickness (Tm) is 0.1293 inch. For the flow rate value (Q) which is 18.36 m3 / h. For the head losses (HL) value that is 1.63 m. while for the pump efficiency value of 52.68%, it is known that the efficiency value is in accordance with the highest value range of the efficiency of the Ebara 50x40 FS2HA (Company requirement) pump. And there is a piping back wash system for cleaning the inner tank

DFIB-SPH study of submerged horizontal cylinder oscillated close to the free surface of a viscous liquid

The hydrodynamics is studied numerically of a horizontal cylinder undergoing forced in-line oscillation beneath the free surface of otherwise quiescent liquid at low Keulegan-Carpenter and Froude numbers. The direct forcing immersed boundary-smoothed particle hydrodynamics (DFIB-SPH) numerical model uniquely combines two well-established techniques: The direct forcing immersed boundary method and SPH. This facilitates accurate evaluation of the potentially violent free surface motions through SPH and the hydrodynamic force on the solid body using a volume integral. A parameter study is conducted covering a range of Keulegan-Carpenter numbers (KC = 3, 7, and 10) and submergence ratios () at fixed Reynolds number (Re = 100) and Froude number (Fr = 0.35). The flow pattern and transverse force coefficient are found to be affected by the proximity of the cylinder to the free surface. Spectral analysis suggests that free surface wave motions are linked to the transverse force acting on the submerged, oscillating cylinder

KAJIAN NUMERIK BACK FLOW CAMPURAN BATUBARA–AIR PERPIPAAN BA-300 PADA PYRITES HOPPER SYSTEM DI PLTU UNIT 8 PT. POMI PAITON

Pulverizer is one of the most important equipment in PLITU PAITON Unit 8, the pulverizer has supporting equipment, one of which is the pyrites hopper system. The functions pyrites hopper is to accommodate coal reject from pulverizer which will be directed towards SSCC using a jet pump. The occurrence of backflow causes damage to the pulverizer on the floor plate. Thermal stress occurs because the backflow of the BA-300 piping flow that enters the pulverizer floor plate temperature drops. This research discusses the backflow causes that occur in the BA-300 pipeline and alternative solutions. This research phase starts from the identification of backflow problems, data collection and literature study regarding backflow on the swing check valve, as well as CFD (Comptational Fluid Dynamics), modeling of existing BA-300 piping system, search and evaluation of alternative solutions. From the simulation results, the coal particles are sandwiched between the disc and casing check valve because the coal particles settle at the bottom of the check valve, which is caused by the amount of flow rate of coal 2.6 kg / s. Of the 6 variations made, the reduction in flow rate with the amount of 1.7 kg / s was not found again pinched coal even though there was still a bit of coal sequestration.Keyword : Backflow, CFD, Swing check valve model

KAJIAN NUMERIK PENGARUH GEOMETRI PIG LAUNCHER PADA PROSES PIG LAUNCHING DI PROYEK JAKARTA TANK TERMINAL (PHASE 2A1)

Abstract - The current design of the cleaning tool used for oil pipe pipes is largely based on the results of experimental information. So there are still questions regarding the behavior of this tool during the launch of the Pig. This study aims to model the pig launching process using the CFD method and then analyze the influence of the pig launcher geometry on the process of translating the pig from the barrel into the reducer and get the force received by the pig on each variation, thus obtaining the most optimal pig launcher geometry. Foam pig and pig launcher are modeled using the Salome Platform and then imported into StarCCM+ software for grid independence, setup simulation, solution simulation and simulation parameter analysis. In the results of the simulation there is a color difference that indicates the big velocity in the pig launcher, the difference in each variation shows the angle of eccentric reducer also affects the velocity profile so that it affects pig translation behavior in the pig Launcher. The geometry of pig launcher eccentric reducer 5 ̊ is the most optimal geometry among the three variations based on the average of each parameter is the smallest translation in the mean y-axis and Z-7.32 e-05 m and 6.72 e-03 m, the average force largest directional axis x 3.332 N, the largest velocity average of the x-axis direction is 0.3425 m/s, and the smallest pig orientation is-0.2682 ̊

Analisa Frost Formation Pada Pipa Berinsulasi Reflux Accumulator Menuju Score Column Reflux Pump di Kilang LPG

The LPG fluid has a very low operating temperature of about -90 ˚F. Thermal insulation to adjust the temperature to the surrounding environment, because of its elements and temperature as the main element for each-hydrocarbon. On the other hand, the activation of the Frost Formation phenomenon in the pipe process around the Score Column allows for the formation of moisture between pipe surfaces with insulation inner layers. In this paper, a CFD (Computational Fluid Dynamics) model is proposed to predict frost formation and growth with the benefit of the nucleation theory. The phenomena of frost formation on a cold surface placed in a stream of humid air are simulated using this model. The results show that the frost grows faster in the upstream region. In the initial period, the mass transfer from water vapor to frost layer mainly contributes to the increase of frost thickness. frost growth rate increase significantly due to flowtime. The effect of humidity and temperature are discussed