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Contact Name
Heru Suryanto
Contact Email
jmest.journal@um.ac.id
Phone
+62341588528
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jmest.journal@um.ac.id
Editorial Address
3rd floor of H5 Bulding, Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Malang Jl. Semarang 5 Malang, Jawa Timur, 65145 Telp 0341-588528 / 0341-551312 ext 298
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Kota malang,
Jawa timur
INDONESIA
Journal of Mechanical Engineering Science and Technology
ISSN : 25800817     EISSN : 25802402     DOI : 10.17977
Journal of Mechanical Engineering Science and Technology (JMEST) is a peer reviewed, open access journal that publishes original research articles and review articles in all areas of Mechanical Engineering and Basic Sciences
Articles 168 Documents
Mechanical Properties of Corner Lap-45 Types Joined Using Friction Stir Welding Setiawan, Widia; Santoso, Nugroho; Winarto, Felixianus Eko Wismo; Krisnaputra, Radhian; Mandala, Wirawan Widya; Maulana, Jibril
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 1 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i12024p178

Abstract

Solid welding has always been concerned with probe design, pins, and joint strength. Many researchers have conducted studies on joints, such as butt joints, lap joints, and T joints, but the results show low strength. This study analyzes the mechanical properties of a new design of a 90o angle joint joined by friction stir welding. This study connected aluminum 6061 using the friction stir welding method using a rectifying jig and a probe with EMS 45 material. The corner joint designs used corner-lap 45 with feed rate as independent variables in 6, 8, 10, 15, and 30 mm/min and dependent variable probe rotation speed at 1000 rpm and shoulder pressure in 584 kg. The results show low feed rates create chips and fish fins on the advancing side, and microstructure test results at low feed rates (6-15 mm/min) indicate the presence of interface bonding. The hardness value of the stir zone also shows an insignificant increase. In the tensile test results, the tensile strength decreases from the base metal value, which then the tensile strength increases along with the increase in feed rate up to a feed rate of 15 mm/min and decreases again at a feed rate of 30 mm/min.
Simulation of the Performance of Kevlar Impregnated Shear Thickening Fluid Ballistic Test Results (STF) Ballistic Test Results Prasetya, Riduwan; Andoko, Andoko; Suprayitno, Suprayitno; Wulandari, Retno; Trihutomo, Prihanto; Mishima, Kenji; Janas, Dawid
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 1 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i12024p054

Abstract

This study explores the enhancement of Kevlar fabric’s ballistic performance through impregnation with Shear Thickening Fluid (STF) for potential application in soft body armor. The experimental approach often fails to elucidate mechanical phenomena critical for the development of lightweight and high-strength body armor designs. To address this limitation, the finite element method, specifically using ANSYS/LS-DYNA R.13, was employed for a comprehensive analysis. The simulation aimed to evaluate the impact of STF on Kevlar fabric by assessing projectile velocity, force exerted by the projectile onto the fabric, displacement, stress distribution, and fabric failure mechanisms. Kevlar yarn was modeled as a shell element formed into fabric with a sine wave profile, investigating two types of STF: SiO2-PEG200 (S0) and SiO2-PEG200-B4C (S1), differing in maximum viscosities. The addition of STF resulted in increased coefficients of friction on Kevlar, with the highest values observed for the SiO2-PEG200-B4C impregnated fabric (  =0.87 and =0.82). The incorporation of the second STF type (S1) significantly reduced the projectile’s velocity from an initial 200 m/s to 153.2 m/s upon impact. Additionally, the force on the S1 fabric surged to 121,556 N, a threefold increase compared to neat Kevlar. STF's influence was further evidenced by enhanced fabric displacement and more uniform stress distribution upon ballistic impact. The fabric's thickening upon failure indicated STF's ability to enlarge the deformation area, facilitating uniform distribution of ballistic kinetic energy across the impact zone. Notably, the fabric impregnated with the second type of STF, featuring boron carbide (S1), demonstrated superior ballistic performance. This study concludes that STF-impregnated Kevlar fabric, particularly the SiO2-PEG200-B4C variant, not only surpasses the ballistic performance of neat Kevlar but also meets the criteria for NIJ Level IIIA standards, highlighting its potential as a highly effective material for advanced soft body armor designs.
Vertical Shaft Kinetic Turbine Performance Using A Cup-Shape Blade Lempoy, Kennie Abraham; Monintja, Nita C.V.; Lakat, Arwanto M.A.
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 7, No 2 (2023)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v7i22023p170

Abstract

The abundant availability of alternative energy sources forms the fundamental foundation for rural energy development. In particular, renewable energy sources are indispensable in rural areas due to their eco-friendly nature and widespread accessibility, which helps preserve the environment by avoiding pollution. Indonesia, a country blessed with vast water resources, especially its rivers, holds enormous potential for harnessing kinetic energy derived from fast-flowing river waters. Effective utilization of this kinetic energy has the potential to address energy shortages in the country. In this context, there is a pressing need to enhance the efficiency of kinetic turbines designed to function as electricity generators in rural regions. This study focuses on evaluating the impact of variables such as the guide angle, water flow speed, and turbine rotation on turbine power and efficiency. The study employs an experimental approach to achieve its objectives, involving tests to assess the performance of a vertical shaft kinetic turbine equipped with bowl blades. Data analysis based on the experimental findings enables the determination of both turbine power and efficiency. The study outcomes demonstrate that the bowl blade type turbine outperforms the curved blade type, primarily due to its larger water capacity, which significantly exceeds that of the curved blade variant. This study emphasizes the potential for harnessing kinetic energy efficiently in rural areas to support sustainable energy development.
Turbine Engine Reliability Analysis Using Reliability Availability Maintainability (RAM) Novareza, Oyong; Darmawan, Zefry; Setyanto, Nasir Widha; Mohamad, Effendi Bin
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 2 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i22024p240

Abstract

Electrical energy is a vital necessity characterized by ever-increasing electricity consumption. The most dominating power plant in Indonesia in supplying electricity is the steam power plant, which is 50%. In its implementation, there is damage that occurs where the highest damage is to the general unit with the highest damage to the turbine unit. Therefore, the author uses the reliability, availability, and maintainability method or RAM. The purpose of this study is to determine the value of RAM on the turbine system at PLN and provide recommendations for improvements to system performance. The results showed that the MTTF and MTTR values of the components are 112,916 minutes and 7,705.91 minutes, respectively. The MTTF value of the equipment indicates in one year the shutdown occurs 4 to 5 times with a relatively short period of time to repair. RAM analysis is carried out and the value is 4.96% (reliability), 93.612% (availability), and 36.44% (maintainability). It can be interpreted that reliability of the system is low due to the frequency of errors, quite difficult to do a repair procedure, but the system is fairly working in good condition in a year period.
Comparative Analysis of the Effect Dual Spark Ignition and Single Spark Ignition on Performance and Exhaust Emissions in Bioethanol-Fueled Engines Permanasari, Avita Ayu; Wahidin, Ahmad Faizal; Ismail, Hasan; Komara, Erwin; Puspitasari, Poppy; Lorenzo, Gina A.
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 1 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i12024p123

Abstract

Bioethanol is an alternative fuel that has a high octane value of around 100 to 110, making it difficult to be applied to spark ignition engines directly. So, it is necessary to make adjustments, including increasing combustion efficiency and thermal efficiency of the combustion chamber by increasing the compression ratio and adjusting the ignition system, both in single spark ignition (SSI) and dual spark ignition (DSI) types. The study aims to determine the effect of SSI and DSI applications on engine performance, specific fuel consumption (SFC), and exhaust emissions using 96% and 99% levels of bioethanol fuel. The results showed that, in general, there was an increase in power, torque, and thermal efficiency as well as a decrease in emissions and better SFC in the DSI engine compared to the SSI engine with 99% bioethanol fuel. The highest power was obtained at 6.89 HP or 5.6% higher than the SSI engine, and peak torque was obtained by 14.95 N.m at 6500 rpm on the DSI engine using 99% bioethanol. Meanwhile, the minimum SFC reduction was obtained at 13.87% lower than that of DSI. The highest thermal efficiency of the DSI engine occurs at 7000 rpm, which is 38.19% when using 96% bioethanol. NOx emission increased when using 99% bioethanol on the DSI engine by 15.58% compared to the SSI engine. CO emissions decreased by 72.51% in the DSI engine with 96% bioethanol fuel. At the same time, CO2 experienced the highest decrease of 76.92% at 5500 rpm on 99% bioethanol DSI engine.
Metal Casting Furnace Design Development Using Computer Simulation Irianto, Ramadhan Wahyu; Pradana, Yanuar R.A.; Suprayitno, Suprayitno
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 1 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i12024p001

Abstract

Metal foundries still rely heavily on crucible furnaces. The current furnace design, which is currently being used by the partner industry, has been found to be not properly designed and will result in a reduction in efficiency. CFD simulation will be used to find the optimal melting furnace design. This research simulation consists of 3 stages: pre-processing, solving, and post-processing. There are two furnace geometries, cylindrical and hexagonal, while the burner location will be divided into 3 positions, namely P1, P2, and P3. The most optimal furnace design will be used as a basis for the verification testing process. The process of comparing the old and the new smelting furnace design is carried out to understand the performance and characteristics of each furnace. The simulation results for the average crucible temperature in the cylindrical furnace were obtained as follows: 288.5 ºC for the P1 burner, 306.2 ºC for the P2 burner, and 284.5 ºC for the P3 burner. Meanwhile, the simulation results show that the average crucible temperature value in the hexagonal furnace is 290.0 ºC for the P1 burner, 281.6 ºC for the P2 burner, and 237.8 ºC for the P3 burner. The verification testing process produced an average crucible temperature value of 237.5 ºC. Furthermore, the comparison test from the old and new furnace designs to melt 2.5 kg of aluminium at 680 ºC with the old furnace took approximately 30 minutes and 33 minutes with the new furnace. The new furnace produced much more uniform melting than the old furnace.
Durability of Thermoplastic Polyurethane Round Belt Joint with Variations in Heating Methods and Cutting Shapes Kusumo, Achmad Sabilarrosyad Prawiro; Murdani, Anggit
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 1 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i12024p187

Abstract

Thermoplastic polyurethane round belts are widely used for conveyors in various industries, particularly in the food and beverage industry, due to their flexible and abrasion-resistant characteristics. These belts are also popular in manufacturing industries because of their ease of joint. However, a common issue arises when the conveyor belt breaks during the production process. This problem can be attributed to the lack of parameters in the belt joining process at companies. Operators do not have a standard parameter for the joining process. When there is an improper joining operation of an operator, the conveyor belt could fail earlier than the expected operation time. Therefore, the conveyor belt failure results in the loss of production time. This downtime can reach up to 15 minutes, i.e. the time required for the belt joining process. Previous studies have identified temperature and heating time as factors that influence the strength of the joint, especially when using a heating plate. Therefore, this research aims to determine the optimal parameters by varying the temperature and length of heating time in the joining process. Additionally, the research explored the impact of different cutting forms on the durability of the round belt joint. The results of this study indicate that the optimal temperature and heating time combination is 100°C for 3 seconds, resulting in a joint strength of 25,274 MPa. Furthermore, the triangular joint shape proved to be the most durable, with a record of 10,021 cycles.
Analysis of Avgas Fuel Spraying Schemes Using the ANSYS Application Approach Putra, Dimas Endrawan; Ilminnafik, Nasrul; Hentihu, M Fahrur Rozy; Kustanto, Muh. Nurkoyim; Yudistiro, Danang; Syuhri, Skriptyan N.H.
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 1 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i12024p071

Abstract

Avgas fuel consumption on Cessna trainer aircraft is very high. However, there has been little research regarding spray impacts in Cessna aircraft engines. The phenomenon of avgas spray colliding with the cylinder wall may occur during fuel injection, resulting in a changed spray radius and height, which will affect the mixing of fuel and air. In several aspects, this affects engine performance and exhaust emissions on Cessna aircraft. This research aims to determine and study the phenomenon of spray impact on avgas-fueled aircraft engines. The fuel spray in the study occurred in the combustion chamber using pressure from a fuel hand pump whose pressure was supplied from a compressor with a pressure adjusted to the original pressure on the aircraft, namely 2 Bar (30 Psi). The experiments in this research used a high-speed camera system to study the phenomenon of avgas spray on walls to get better spray distribution. The results of this research were processed using the CFD application. The result of this research is that the greater the pressure, the more concentrated the resulting jet will be on the jet wall so that the atomization of the fuel jet will be dispersed. When the burst occurs, a change of 3.80e+00 occurs compared to other burst pressures.
Photocatalytic Scheme with External Magnetic Field on Coffee Waste in Hydrogen Production Alphanoda, Abid Fahreza; Prasetyo, Eko; Broto, Wisnu
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 7, No 2 (2023)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v7i22023p181

Abstract

Photocatalytic is considered a deadlock-breaking technology for renewable energy and lowering environmental pollutants. Photocatalytic efficiency efforts are improved by activating the photocatalyst to introduce an external magnetic field. This review highlights recent breakthroughs by comparing original coffee waste, activation of coffee waste with the addition of catalysts, and manipulation of spin electrons by applying external magnets. Characterization was done with FTIR to look at chemical bonds, UV-Vis with Tauc's Relation approach to measure bandgap, and material morphology using SEM EDX. The increase in photocatalyst activation aligns with the decrease in bandgap value. The rate of decline in bandgap is in line with the rate of acceleration of hydrogen production. Adding an external magnetic increases hydrogen production up to 1.5 times greater than the original photocatalytic.
Performance Enhancement of Dye Sensitized Solar Cell (DSSC) through TiO2/rGO Hybrid: Comprehensive Study on Synthesis and Characterization Hatib, Rustan; Anwar, Khairil; Magga, Ramang; Astak, Muh Anjas; Widhiyanuriyawan, Denny; Wardoyo, Wardoyo
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 1 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i12024p138

Abstract

The TiO2 film is immersed in a graphite oxide solution, preparing it for thermal reduction, which converts the graphite oxide to reduced graphene oxide (rGO). This process produces rGO hybrid TiO2 photoanodes for dye-sensitized solar cells (DSSC). rGO in the TiO2 structure prevents electron recombination and improves overall efficiency. The main advantage of this method is its ability to prevent loss of rGO during the sintering process, which is a common problem with other methods. The study investigated heating temperatures ranging between 300˚C, 350˚C, 400˚C, 450˚C, and 500˚C to determine optimal conditions. The presence of rGO in the photoanode structure was confirmed via X-ray diffraction and Fourier transform infrared spectroscopy analysis. JV (current-voltage density) measurements of DSSC based on TiO2/rGO photoanode revealed that the highest photoelectric conversion efficiency (0.1923%) was achieved at 400˚C, much higher than other temperature variations. The findings demonstrate the effectiveness of a simple low-temperature thermal reduction process in producing graphene suitable for semiconductor applications in DSSC. The RGO produced through this method not only improves energy conversion efficiency but also outperforms traditional graphite electrodes. By optimizing the thermal reduction process and fine-tuning the heating conditions, this study advances the practical application of graphene-based materials in solar cell technology. This method overcomes the loss of rGO during sintering, ensuring its beneficial properties are retained. Overall, this study shows that low-temperature thermal reduction is an efficient technique to improve DSSC performance through the incorporation of reduced graphene oxide.