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Contact Name
Vivien Suphandani Djanali
Contact Email
jmes@its.ac.id
Phone
+62315922941
Journal Mail Official
jmes@its.ac.id
Editorial Address
JMES The International Journal of Mechanical Engineering and Sciences Editorial Office Jurusan Teknik Mesin, ITS Kampus ITS Sukolilo Surabaya 60111 Building C, Floor 2 Indonesia
Location
Kota surabaya,
Jawa timur
INDONESIA
JMES The International Journal of Mechanical Engineering and Sciences
ISSN : -     EISSN : 25807471     DOI : https://dx.doi.org/10.12962/j25807471
Topics covered by JMES include most topics related to mechanical sciences including energy conversion (wind, turbine, and power plant), mechanical structure and design (solid mechanics, machine design), manufacturing (welding, industrial robotics, metal forming), advanced materials (composites, nanotube, metal foam, ceramics, polymer), metallurgy (corrosion, non-destructive testing, heat treatment, metal casting), heat transfer, fluid mechanics, thermodynamics, mechatronics and controls, advanced energy storage and devices (fuel cell, electric vehicle, battery), numerical modelling (FEM, BEM).
Articles 93 Documents
Experimental and Numerical Study of Two Dimensional Flow of Bubble Separation over the Leading of Thickness Plate Herman Sasongko; Abdul Haris Irfani
JMES The International Journal of Mechanical Engineering and Sciences Vol 4, No 2 (2020)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v4i2.7870

Abstract

Various design modifications made by transportation equipment companies aim to increase the efficiency of fuel consumption. One of them is by reducing the drag force. This can be done by controlling passive turbulent boundary layers. The addition of rounded shape on the leading edge which is correlated with the length of the plane is one way of controlling the passive turbulent boundary layer which can accelerate the transition from the laminar boundary layer to the turbulent boundary layer. Therefore, this study aims to determine the effect of the Reynolds number and flow support length on the flow characteristics so that the downstream separation can be delayed. This research was conducted by experimental and numerical methods. The Reynolds number used is Ret = 5.08 × 104 and Ret = 8.46 × 104 . The test part of this research is the rounded leading edge of thick plate with a plane length of c/t = 6.5 and c/t = 10. The amount of rounded on the leading edge, the height of the test model and the length of the trailing edge are 10 mm, 100 mm, and 300 mm, respectively. The parameters varied in this study were the flow bearing field length (c/t) and the Reynolds number (Ret). Two-dimensional, steady numerical simulation was carried out using ANSYS Fluent software. The turbulence model used is k − kl − ω. The results obtained in this study are the longer the flow bearing plane and the greater the Reynolds number can delay the separation on the upper side of the circular front edge of the thick plate. The optimal length of the separation delay time is c/t = 10 with Ret = 8.46 × 104 .The separation bubble profile at c/t = 10 with Ret = 8.46 × 104 has length (x/c) = 0.129, thickness (y/t) = 0.1363, and angle (Θ) = 30.3 ◦ with the form factor (H) at point O 1.424. Overall the optimal variation is at c/t = 10 with Ret = 8.46 × 104 where the point of separation occurs when x/c = 0.945.
Numerical Study of Characteristics Root Canal Irrigation using Open-Ended Needle Positive Pressure and Negative Pressure Method Fajar Dwi Yudanto; Wawan Aries Widodo; Suwarno Suwarno
JMES The International Journal of Mechanical Engineering and Sciences Vol 4, No 1 (2020)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v4i1.7128

Abstract

This study aims to determine the characteristics of fluid flow through root canal irrigation using positive and negative pressure methods used CFD (Computational Fluid Dynamic) software by modeling root canals and needle insertion in the root canals. This modeling used a steady flow, an incompressible flow, and uniform flow at the inlet side, and the roughness of the root canal wall surface is neglected (smooth wall). The open-ended needle with different insertion lengths applied for each method with a flow rate of 0.2 mL/s or about 6.63 m/s and the Reynolds number is 1376 (Laminar). The fluid has 2.5% of NaOCl with the density of 1060 kg/m3 and 0.001 Pa.s of fluid viscosity. After considering factors such as velocity, dynamic pressure, and wall shear stress in both methods, a greater velocity value in the apical region is determined by using a positive pressure method. Meanwhile, the negative pressure method shows the ability to lift higher due to shear stress, which is more evenly distributed upwards. However, both methods are qualified for irrigation replacement in the apical region.
Numerical Study of Savonius Wind Turbine Rotor with Elliptic Angle Shape Variation Antonius Hadi Sudono Putranto; Vivien Suphandani Djanali; Bambang Arip Dwiyantoro
JMES The International Journal of Mechanical Engineering and Sciences Vol 3, No 2 (2019)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v3i2.9367

Abstract

The Savonius wind turbine uses a half-cylinder blade which is often called a bucket assembled so that the cross-section forms an "S". This turbine is seen in the form of a half-cylinder consisting of a concave side and a convex side. This turbine is one type of Vertical Axis Wind Turbine (VAWT) that uses the difference in drag forces between the two buckets to be able to rotate the rotor. Therefore this rotor has the ability to self-start, which other wind turbines do not have, even so, the performance of the turbine. Savonius wind is still relatively low, so that it cannot be applied until now. Many studies have been carried out to improve performance, some of which include adding shielding, end plates, changing the shape of the blades, gap overlap, and others. The analysis in this numerical study included a comparison of the performance of conventional Savonius wind turbines and elliptic Savonius wind turbines with an assumed steady flow 2D flow and using turbulent viscous transitions k-kL-ω and k-ω SST with variations in flow velocity and angle of incidence of flow to the position of the rotor of the Savonius turbine. This results evaluated were the static torque coefficient with respect to the rotor position, the pressure distribution along the blade surface, and the wind flow characteristics near the rotor. The results of this study indicated that the modified wind turbine rotor had a higher static torque coefficient at low speeds. The two types of turbine rotors had relatively the same self-starting capability at high speeds.
Failure Analysis of Bend Tube Preheater on Heat Recovery Steam Generator R. Sony Endardo Putro; Arif Hariyadi; Suwarno Suwarno
JMES The International Journal of Mechanical Engineering and Sciences Vol 1, No 1 (2017)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v1i1.2222

Abstract

The combined cycle power plant (PLTGU) is the second largest percentage of electrical production method which is 26% of all electrical production technology in Indonesia. One of the components in combined cycle power plant is the heat-recovery steam generator (HRSG), which serves as heat-exchanger between hot gasses from gas turbine cycle and water from steam turbine cycle. There are four stages on HRSG, preheater, economizer, evaporator, and superheater. In the present work, there is a case of thinning on a bend tube preheater which exceeds the tolerance limits, therefore the purposes of this research determine the cause of failure and determine the failure mechanism on bend tube preheater. Thinning of bend tube preheater occurred due to corrosion from both the inside surface and outside surface. Corrosion that occurred on the inside surface of bend tube preheater caused by a reaction between water and metal surface of the tube. Corrosion on the outside surface could be happen caused by a reaction between the hot gas and metal surface of the tube. Largest thinning rate occurred on bend area of bend tube preheater caused by deformation itself, it induces local reduction of breakdown potential.
Numerical Study of Temperature and Air Velocity Distribution In Oil Filling Factory Hernawan Novianto; Prabowo Prabowo
JMES The International Journal of Mechanical Engineering and Sciences Vol 1, No 2 (2017)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v1i2.2796

Abstract

This paper describes the use of CFD modeling to analyze the thermal comfort in the oil filling factory which has an area of 3000 m2.the need for this analysis comes from an uncomfortable condition that is felt by the workers of the factory. A 3D simulation using FLUENT software 6.3.26 conducted to analyze the temperature and velocity distribution in the plant room. The water is assumed as an incompressible ideal gas, steady flow, turbulence models used k-ε standard, the SIMPLE algorithm and second order upwind discretisation. Analysis was conducted on existing models and propose models, whereby on a model propose, the diffuser is installed above the workers with a height of 4,2 m above the floor, the velocity of supply air diffuser is varied from 1,5 m/s, 2 m/s, and 2,5 m/s. The simulation results show that the temperature distribution in the existing conditions in the range of about 34-36 ° C, this value exceeds the thermal comfort standards specified by ASHRAE. The simulation results show that the proposed model better temperature distribution, where the temperature is generated in the range of ASHRAE thermal comfort criteria, ranging from 24-26 °C, and the supply air velocity at the diffuser inlet of 1,5 m/s recommended for use in AHU system. For the 20 units of the diffuser with inlet velocity of 1,5 m / s, the mass flow rate that should be handled by a cooling device is 9 kg/s and require a cooling capacity of 0,128 MW. This is 58% more efficient than cooling the entire room factory.
The Effect of Variation in the Number of Pole and Air Gap on Torque Density on Radial Magnetic Spur Gear with Magnetic Block Agus Sigit Pramono; Alfiana N Hidayati
JMES The International Journal of Mechanical Engineering and Sciences Vol 4, No 1 (2020)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v4i1.7828

Abstract

Magnetic gear is an alternative to mechanical gear, where the magnetic gear has the advantages of no noise, minimum vibration, no maintenance required, increased reliability, overload protection capability, no physical contact between gears, and the resulting torque density is still below the mechanical gear torque density. In this research, the variation of the number of poles and air gap in the amount of torque density produced was carried out. The permanent magnet material used is Neodymium type with a gear ratio of 1:2. In the variation of the number of poles used by pairs of 4 and 8 poles, 8 and 16 poles, 10 and 20 poles, and 12 and 24 poles, in the variation of the air gap used, namely 1 mm, 1.2 mm, 1.3 mm, 1.4 mm and 1.5 mm. Magnetic gear performance can be seen through analysis simulation with the 3D finite element method using Finite Elements Software. The type of simulation used is the magnetostatic analysis method at the processing stage and the transient analysis method at the post-processing stage. From the simulation results, it is concluded that the greater the number of poles, the greater the torque density produced, and the closer the air gap distance will result in a greater torque density. The effect of the number of poles on the torque density is more significant than the effect of the air gap.
Experimental Study of the Effect of Magnetization on Bioethanol Injectors on Spray Characteristics for Applications in the SINJAI-150 Engine Amalia Dwi Utami; Bambang Sudarmanta; Budi Utomo Kukuh Widodo; Ary Bachtiar Krisna Putra; Is Bunyamin Suryo
JMES The International Journal of Mechanical Engineering and Sciences Vol 3, No 2 (2019)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v3i2.9389

Abstract

In general, the hydrocarbon molecules in the fuel perform vibrational activity towards the core and attract each other, forming clustering molecules. Induction of a magnetic field in the fuel flow can change the hydrocarbon molecules so that their arrangement becomes more regular (de-clustering). The induction of the magnetic field in this research utilized a coil that was fed by an output current from the SINJAI-150 engine alternator. Magnetic field placement was placed before Bioethanol E100 fuel entered the injector. Observation of the magnetization of the fuel was carried out molecularly with the FTIR (Fourier Transform-Infra Red Spectroscopy) test and observing the characteristics of the fuel spray at the injector output. The results obtained were an increase in the fuel transmittance of Bioethanol E100 up to 41.31% for C-H compounds, 48.8% for C-O compounds, and 114% for O-H compounds compared to standard conditions. In the spray characteristics, there was an increase in the spray angle up to 2 and a decrease in the Sauter Mean Diameter (SMD) to 1.312 mm, due to a decrease in the value of the fuel properties in the form of surface tension, viscosity, and density up to 2.6%, 10.28% and 10.15% from the standard state without magnetization. As a result of decreasing the density value, the mass flow rate of the fuel decreases to 10.28% from the standard conditions at 2,000 rpm.
Study of Flow Characteristics in a Closed-Loop Low-Speed Wind Tunnel Ahmad Anis; Sutardi Sutardi
JMES The International Journal of Mechanical Engineering and Sciences Vol 1, No 2 (2017)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v1i2.3900

Abstract

Wind tunnel is an element or experimental device that plays an important role in the development of aerodynamics. In general, there are two types of wind tunnels: open-loop wind tunnels and closed-loop wind tunnels. Furthermore, based on the flow velocity in the wind tunnel, the wind tunnel can also be categorized into several types: low-speed wind tunnel and high-speed wind tunnel, including sub-sonic and supersonic wind tunnels. In this study it is used a low-speed closed-loop wind tunnel type. The maximum atainable velocity of airflow in the wind tunnel is about 46 m/s with turbulence intensity (TI) as low as 0.41 percent. The flow parameters that being evaluated in this study include the velocity profiles and intensity of turbulence (TI) in some parts or sections of the wind tunnel. Pressure measurements in the wind tunnel are performed using a Pitot tube connected to a calibrated pressure transducer. The measured values of pressures are then converted into the fluid velocities and turbulence intensities. The results show that the flow quality in the main test section of the wind tunnel is good enough. The intensity of the flow turbulence on the inlet side of the test section is about 0.41 percent at the centerline velocity of approximately 40 m/s. In some parts of the wind tunnel, turbulence intensity is still relatively high, as in the small elbow outlet where TI is higher than 18 percent.
Numerical Study of Epoxy-Ramie Fiber Composite as a Type IV Ballistic Resistant Material Sutikno Sutikno; Rayhan Fikriandry Rizal; Ahmat Safaat
JMES The International Journal of Mechanical Engineering and Sciences Vol 5, No 1 (2021)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v5i1.8772

Abstract

This paper studies the response of epoxy-ramie fiber composite as ballistic-resistant material using a finite element model. The simulation test was conducted by varying the number of layers and referred to NIJ 0101.06 Type IV as the boundary condition. The model used was a panel made from epoxy-ramie composite laminates with a certain thickness and a 7.62 mm bullet. NIJ states that ballistic material should withstand penetration, and the back-face signature (BFS) should not exceed 44 mm. The impact energy is not briefly mentioned in NIJ failure criteria. The properties of the composite and the bullet were obtained from scientific literature and previous study. The effect of the number of layers on impact response was evaluated by the penetration, deformation, BFS, and absorbed energy.
Effect of Asymmetric Geometry on the Flexibility of Stent Achmad Syaifudin; Ryo Takeda; Katsuhiko Sasaki
JMES The International Journal of Mechanical Engineering and Sciences Vol 1, No 1 (2017)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25807471.v1i1.2183

Abstract

Mechanical characteristic assessment of the new stent design is important to improve the performance during the stenting process. Stent with good performance in geometric assessment should pass several tests in the unexpanded and expanded condition. The FEM assessment is expected to replace the actual mechanical assessment to save the cost and time of the manufacturing. In this study, the FEM assessment is conducted using the structural nonlinear analyses in ANSYS R15.0. The stent type used in the simulation is the Asymmetric stent and the Sinusoidal stent. The assessments included in this study are the flexibility test on the unexpanded condition (single-load and multi-load) and that on the expanded condition under single point loading. The three-point bending test is chosen as the flexibility test, either for the unexpanded or expanded condition, due to its simplicity. To restrain angular deformation and more save the computation process, a symmetry model (due to longitudinal and angular plane) of each stent type is constructed. By utilizing Multi Point Constraint (MPC) element, the loading is subjected over a pilot node at the center line of the stent. The analysis results showed that Asymmetric stent has lower flexibility comparing with a Sinusoidal stent in the unexpanded configurations. In the case of an Asymmetric stent, its inflated-side is more flexible than the fixed-side.  

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