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Multi-Objective Optimization of MEMS-based Box Pattern Microheaters Using Response Surface Method Setyawati, Onny; Choiron, Moch. Agus; Bangert, Axel; Sandhagen, Carl
Elinvo (Electronics, Informatics, and Vocational Education) Vol. 9 No. 2 (2024): November 2024
Publisher : Department of Electronic and Informatic Engineering Education, Faculty of Engineering, UNY

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/elinvo.v9i2.77133

Abstract

We present a response surface method to evaluate multi-objective optimization for MEMS-based microheater design. Box pattern, the standard microheater shape, was selected in this study since it has a uniform temperature distribution compared to other patterns. The optimum parameters are used to obtain the maximum total current density and Joule heat.  Based on a hybrid of the Response Surface Method and Central Composited Design, the model simulation emerged with 25 sets of Design Experiments.  As expected, the voltage is proportional to the increased output temperature and Joule heat of the microheater. Material thermal conductivity, anchor length and thickness of the heating element are included as design variables for the optimization. The microheater thicknesses of 4.23 - 4.55 µm, length of 40 µm and thermal conductivity of materials of approximately between 52 to 66 Wm-1K-1 became the optimized results at 1 V input voltage to obtain a maximum Joule heat of 4.9x105 W/mm3 and total current density of 5.6x107 mA/mm2.
COMPUTER SIMULATION INVESTIGATION OF CRASH BOX DESIGN AS SAFETY-PROTECTION TECHNOLOGY FOR INDONESIA HIGH SPEED TRAIN Musyaffa, Dzikri Amali; Choiron, Moch. Agus; Irawan, Yudy Surya; Hidayati, Nafisah Arina; Taryono, Taryono
International Journal of Mechanical Engineering Technologies and Applications Vol. 4 No. 1 (2023)
Publisher : Mechanical Engineering Department, Engineering Faculty, Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/MECHTA.2023.004.01.11

Abstract

The crashworthiness of a railway vehicle has been developed to provide energy absorption capacity and efficiency of energy absorption. This study presents a computer simulation to determine the energy-absorbing structure of the new addition of a crash box design on the Indonesian high-speed train in a collision scenario. The crashworthiness analysis in the crash box is done with software based on finite element methods. The crash box is modeled as a thin-walled structure located in coupler housing, between the draft gear and the car frame. The test model was carried out according to the 2019 SNI 8826 standard using a frontal impact test with an impactor mass of 38.807 kg and a speed of 10 m/s. The pattern of deformation and energy absorption is obtained by calculating the area under the graphical curve of the relationship between the force reaction and the displacement obtained from the simulation. The deceleration of the train is obtained from the graph of acceleration against time on the impactor. The simulation results show that the addition of a crash box design as an energy absorption module on a safety protection technology for railway vehicles can reduce the severity of the impact and improve passenger safety. The application of the initial crash box model also shows an unacceptable train deceleration in the SNI 8826 test standard.
Stress analysis of steam turbine rotor using Fluid-Structure Interaction simulation Fauzi, Katanda Fajar; Choiron, Moch. Agus; Widodo, Agung Sugeng; Irawan, Yudy Surya; Darmadi, Djarot B.; Purnowidodo, Anindito
GMPI Conference Series Vol 3 (2024): The 10th Asian Academic Society International Conference (AASIC)
Publisher : Gemilang Maju Publikasi Ilmiah (GMPI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.53889/gmpics.v3.419

Abstract

Steam Power Plant generates electricity due to a device that extracts heat energy from steam and converts it into mechanical work on the rotor. Turbines operate at high pressures and temperatures which may cause potential failures in the rotor. This study aims to determine the stress distribution on the turbine rotor to predict potential failures. The turbine studied is a 15 MW steam turbine with a rotation speed of 3000 rpm, inlet steam pressure of 2 MPa, and inlet steam temperature of 471.2 OC. The study focused on the Curtis stage. Fluid-Structure Interaction (FSI) simulation was performed to determine the interaction between the fluid and the turbine rotor. Computational Fluid Dynamic (CFD) was performed to determine the temperature and pressure hitting the rotor. The temperature and pressure distribution data from the CFD simulation is transferred to the structural simulation as the load received by the rotor. In addition to fluid loads, the rotor experiences centrifugal loads due to rotation and gravity loads. The largest stress received by the turbine rotor is at the front of the rotor with a stress of 347.39 MPa.
DEVELOPMENT OF SYMMETRIC MODEL FOR FLUID-STRUCTURE INTERACTION SIMULATION ON STEAM TURBINE ROTOR Fauzi, Katanda Fajar; Choiron, Moch. Agus; Widodo, Agung Sugeng; Solikhin, Atfalus Solikhin
International Journal of Mechanical Engineering Technologies and Applications Vol. 6 No. 2 (2025)
Publisher : Mechanical Engineering Department, Engineering Faculty, Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/MECHTA.2025.006.02.2

Abstract

Development of technology allows stress analysis of steam turbine rotor to be performed non-experimentally using Fluid-Structure Interaction (FSI) simulation. FSI modeling requires high computational power and a long time to complete. In this study, a symmetric model is used to reduce the computational time. The part size of the symmetric model is investigated for its influence on the FSI simulation results. The full, 1/5, 1/30, and 1 blade models were investigated. Fluid domain is solved by Computational Fluid Dynamic (CFD) simulation. Afterwards, pressure and temperature distributions are mapped to the structural simulation to determine the structural response in terms of stresses. The pressure distribution, temperature distribution, and stress distribution of each model were compared. The contours of pressure distribution, temperature distribution, and stress distribution have the same trend for all models. The pressure and stress value on sharp shape of the blade tip is slight difference due to insufficient number of elements.
Hardening Baja AISI 1045 Menggunakan Gel Aloe Vera Sebagai Media Pendingin Budiyanto, Eko; Choiron, Moch. Agus; Darmadi, Djarot B.
Jurnal Rekayasa Mesin Vol. 7 No. 2 (2016)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jrm.2016.007.02.3

Abstract

Quenching is a cooling method of heat treatment for metal hardening. Quenching refers to the process of rapidly cooling metal parts from the austenitizing or solution treating temperature, typically from within the range of 815 to 970 °C for steel. The selection of a quenchant medium depends on the hardenability of the particular alloy, the section thickness and shape involved, and the cooling rates to achieve the desired microstructure. The liquid quenchants of oil is commonly used in industrial manufacture. But, oil is not environmental. The aim of this research research is to find new quenchant for change oil as quenchant to more environmental. Gel aloe vera is purposed for it. The material used in this study is AISI 1045 steel. Cooling curve and cooling rate is measured by finite element model, ANSYS APDL 14.5. True experimental is done to view microstructure and measure hardness of steel. Simulation result shown that gel aloe vera has almost similar cooling curve and cooling rate with oil. Microstructure result of steel for gel aloe vera as quenchant is martensite in surface, bainite in center, and pearlite in between surface and center. Hardness number of steel for gel aloe vera as quenchant is 189.63 HVN in surface, 182.566 HVN in center, and 162.866 HVN in between surface and center. By simulation and true experimental analisys concluded that gel aloe vera has opportunities to change oil as quenchant for hardening process.
REKAYASA DESAIN CIRCULAR HYBRID CRASH BOX UNTUK PENINGKATAN PERFORMA KELAYAKAN TABRAK Wakhidah, Delia Hani; Choiron, Moch. Agus; Irawan, Yudy Surya
Jurnal Rekayasa Mesin Vol. 15 No. 3 (2024)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/jrm.v15i3.1403

Abstract

In previous studies, hybrid crash boxes have been developed because it show better energy absorption characteristics. Circular hybrid crash box combine the advantages of low-density of composite with stable deformation of metal provide a potential energy absorption device. Tests were carried out experimentally and iumerically under frontal load. This study aims to determine the energy absorption characteristics of two different configuration of hybrid material compositions using Aluminum Alloy 6063 and T300-epoxy Carbon Fiber composites. Present two typical configurational schemes, namely Al-Ko (i.e. a metal outer tube internally filled with an inner carbon fiber reinforced plastic (CFRP) tube) and Ko-Al (i.e. an outer composite tube internally filled with an inner metal tube). Composite layups arrangement with fiber orientation direction [0,90]10. First, the simulation models were developed and validated by comparing the damage modes and crashworthiness indictors with the dedicated experimental study. Second, the interactive effects of different configuration hybrid tubes were investigated by analyzing the discrepancies in the deformation pattern and internal energy absorption of each material through the validated simulation models. The test results show that the greatest energy absorption occurs in the Al-Ko model of 7401.4 J. This hybrid crash box has an energy absorption value of 11% greater compared to the sum of the energy absorption of aluminum tubes (3746.5 J) and composite tubes (2923.4 J).
COMPUTER SIMULATION INVESTIGATION OF CRASH BOX DESIGN AS SAFETY-PROTECTION TECHNOLOGY FOR INDONESIA HIGH SPEED TRAIN Musyaffa, Dzikri Amali; Choiron, Moch. Agus; Irawan, Yudy Surya; Hidayati, Nafisah Arina; Taryono, Taryono
International Journal of Mechanical Engineering Technologies and Applications Vol. 4 No. 1 (2023)
Publisher : Mechanical Engineering Department, Engineering Faculty, Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/MECHTA.2023.004.01.11

Abstract

The crashworthiness of a railway vehicle has been developed to provide energy absorption capacity and efficiency of energy absorption. This study presents a computer simulation to determine the energy-absorbing structure of the new addition of a crash box design on the Indonesian high-speed train in a collision scenario. The crashworthiness analysis in the crash box is done with software based on finite element methods. The crash box is modeled as a thin-walled structure located in coupler housing, between the draft gear and the car frame. The test model was carried out according to the 2019 SNI 8826 standard using a frontal impact test with an impactor mass of 38.807 kg and a speed of 10 m/s. The pattern of deformation and energy absorption is obtained by calculating the area under the graphical curve of the relationship between the force reaction and the displacement obtained from the simulation. The deceleration of the train is obtained from the graph of acceleration against time on the impactor. The simulation results show that the addition of a crash box design as an energy absorption module on a safety protection technology for railway vehicles can reduce the severity of the impact and improve passenger safety. The application of the initial crash box model also shows an unacceptable train deceleration in the SNI 8826 test standard.