https://ejournal.unib.ac.id/rekayasamekanika/issue/feedRekayasa Mekanika2022-12-20T00:41:15+00:00Hestiawanhestiawan@unib.ac.idOpen Journal Systems<p>Rekayasa Mekanika is scientific journal on mechanical sciences and engineering field, either pure or inter disciplinary works. The journal annually publishes articles series in two volumes every April and October. Authors are cordially invited to submit his/her research, review or monograph papers in English or Indonesian.</p>https://ejournal.unib.ac.id/rekayasamekanika/article/view/25456MODAL ANALISIS PADA ROTARY KILN DENGAN MENGGUNAKAN METODE ELEMEN HINGGA2022-12-20T00:26:33+00:00Wahyu Rahmat Hidayatwahyurahmat291@gmail.comDedi Suryadidedisuryadi@gmail.com<p><em>This research is based on the general damage to the rotary kiln due to continuous use. Then the results from the burned in a Rotary Kiln So we need a prevention to overcome it. Testing the vibration mode on a rotary kiln machine is a solution to overcome the limit on the use of the finite element menthod. With the completion procedure of finite element software with the step of Rotary Kiln Geometry Modeling Process, Rotary Kiln Geometry Import Process, Rotary Kiln Geometry Import Process, Material Data Input Process, Meshing Process, Determination of Boundary Conditions, Running Process, and Port Processing. The results of this study are from the finite element simulation obtained in the form of the frequency value of the natural response of the structure and the deflection due to vibrations that occur in the rotary kiln Indarung IV PT Semen Padang. And it was concluded that the vibration mode experienced by the rotary kiln has a natural frequency value, the vibration mode of the rotary kiln structure obtained a maximum value of 63.3 Hz, while the minimum value obtained a value of 41.805 Hz. The maximum deflection of the rotary kiln is obtained from the analysis results of 0.058981 mm while the minimum deflection value is 0.045 mm.</em></p>2022-10-04T00:00:00+00:00Copyright (c) 2022 https://ejournal.unib.ac.id/rekayasamekanika/article/view/25457ANALISA KOROSI PADA TANGKI REAKTOR TRIGA 2000 MENGGUNAKAN METODE INSPEKSI ULTRASONIK DAN INSPEKSI VISUAL (UNDERWATER CAMERA) 2022-12-20T00:29:22+00:00ShafiraShafira@gmail.comHendri HestiawanHestiawan@gmail.comPutra Bismantoloputrabismantolo@gmail.com<p><em>A reactor is a process device where a reaction takes place, be it a chemical or nuclear reaction and not physically. Nuclear reactors are used for various purposes, namely to create, regulate, and maintain a nuclear chain reaction at a constant rate. One method of monitoring corrosion is using an ultrasonic device to measure the thickness of the tank wall and an underwater camera tool to visually see the damage that has occurred and will provide a quantitative estimate of the corrosion rate that occurs in the system by comparing the initial weight and weight after a certain time. The corrosion rate value on the TRIGA 2000 reactor wall is obtained through the weight reduction method, and has an average corrosion value of 0.10 mmpy, while the type of corrosion that occurs on the TRIGA 2000 reactor wall is the type of intergranular corrosion. protective coating by coating organic compounds (lubricant) and controlling humidity and temperature.</em></p>2022-10-04T00:00:00+00:00Copyright (c) 2022 https://ejournal.unib.ac.id/rekayasamekanika/article/view/25458PENGARUH PEMBEBANAN TERHADAP ARUS EKSITASI PADA GENERATOR 2022-12-20T00:32:41+00:00Hamdan Rizal Maulanahamdanrizal1117@gmail.comAgus SuandiAsuandi@gmail.comHelmizarhelmizar@gmail.com<p><em>The generator in the hydropower system is used to convert mechanical energy originating from the turbine rotation into electrical energy by producing an electromotive force. Excitation is one of the most crucial parts of the Generator system, where excitation plays a role in forming/producing electromagnetic flux, resulting in an induced emf. The amplifying current is used to adjust the magnitude of the output voltage according to the applied load. The tool used to regulate the excitation current is the Automatic Voltage Regulator (AVR). The differential loading on the generator changes every time. Therefore a power plant must be able to generate electricity in accordance with the magnitude of the changing load. In power generation, these loading fluctuations can be overcome by adjusting the water valve opening and the excitation current flowing to the electromagnet coil on the generator rotor with constant rotor rotation by the AVR so that electric power is generated according to the applied load. The purpose of this study is to analyze the effect of the load on the excitation current. The results obtained are the load has an effect on the excitation current.</em></p>2022-10-04T00:00:00+00:00Copyright (c) 2022 https://ejournal.unib.ac.id/rekayasamekanika/article/view/25459PENGARUH VARIASI INFILL DAN SPEED PRINTING TERHADAP SIFAT MEKANIK ADDITIVE MANUFACTURING2022-12-20T00:35:28+00:00Fernando Desfriandi Saragihfdesfriandi@gmail.comA. Sofwan FASofwan@gmail.comYovan WitantoYWitanto@gmail.com<p><em>Additive Manufacturing (AM) is a production process that does not remove or remove some of the material in the production process but adds material. The added material is extruded by means of Fused Deposition Modeling (FDM) technique. The way it works is to create a number of layers or layers one on top of the other. The software application used is Inventor to create 3D models in the form of STL files. Then the STL file is opened in the Ultimaker Cura (UC) application, to create a Numerical Code in G-Code which is used as a control on a 3D printing machine. The filler material used to produce molds is Polylatic Acid (PLA). PLA filament is very widely used in the manufacturing process, because this PLA can produce strong and very neat prints. The general print temperature of PLA is between 180oC to 220oC. The purpose of this test is to find out the steps for implementing the AM process and to analyze the mechanical properties of the AM product using the FDM technique. In this study, the printed material was based on ASTM D638 type IV. This research was conducted to determine the effect of variations in infill and printing speed on printed results, with a horizontal orientation of the printing angle of 0o. The infill variations are line infill and concentric infill with printing speeds of 50mm/s and 60mm/s. The research procedure is to make a 3D printing model, the manufacturing process, and the testing process. The results showed that the choice of infill and speed printing variations had an effect on the mechanical properties. The mechanical properties of printing products differ according to the mode and speed. The infill line mode provides greater mechanical strength than that produced in concentric infill. At a speed of 60 mm/s, the product strength of the infill line mode is 32.5 MPa greater than the 27 MPa strength of the printed product from the concentric infill mode.</em></p>2022-12-04T00:00:00+00:00Copyright (c) 2022 https://ejournal.unib.ac.id/rekayasamekanika/article/view/25460MAINTENANCE DAN INSPECTION PADA RUNNER TURBIN 2022-12-20T00:38:19+00:00AM Saifutaqi Fatwa Mayfifatwamayfi4@gmail.comNurul Iman Supardinis@gmail.comAngky PuspawanApuspawan@gmail.com<p><em>The PLTA TES is a generator that relies on water as the driving force for a turbine unit system. There are 7 PLTA Tes turbine units that are still operating with alternating working hours. In keeping a turbine unit operating properly, one way is to do maintenance and general inspection (GI). Maintenance is one way to keep a tool or object from being damaged. Then General Inspection (GI) is a process of activities in the PLTA Test company in checking, measuring, adjusting, repairing and testing one turbine unit in operating for 20,000 hours on a regular basis so that the unit can operate better than before, maintenance is carried out. One of the turbine components that is the object of maintenance is the runner. The runner is the heart of a turbine so that it can operate by relying on flowing water so that the runner can rotate. Runners are given a spot check to see if there is a crack in the runner's condition and measure the runner's clearance so that there is no excessive friction when the runner is operating and the runner is not thirsty.</em></p>2022-10-04T00:00:00+00:00Copyright (c) 2022 https://ejournal.unib.ac.id/rekayasamekanika/article/view/25461SIMULASI ANALISIS VELOCITY ALIRAN FLUIDA PADA TANGKI REAKTOR NUKLIR MENGGUNAKAN METODE COMPUTATIONAL FLUID DYNAMICS (CFD) 2022-12-20T00:41:15+00:00Mifta Aroyyanimiftaaroyyani90@gmail.comAgus NuramalAnuramal@gmail.comHendri HestiawanHestiawan@gmail.com<p><em>Center for Applied Nuclear Science and Technology (</em>Pusat Sains dan Teknologi Nuklir Terapan /<em>PSTNT) is a work unit that is under and directly responsible to the Deputy for Nuclear Science and Applications of Nuclear Technology, National Nuclear Energy Agency. In PSTNT Bandung, the function of the tank is as a container to place the reactor components, the reactor shield for the heat exchanger and as a place for nuclear reactions to take place. In nuclear reactor tank flow distribution ocures in various velocity.The purpose of this practical work is to analyze the velocity of fluid flow in the reactor tank from the inlet flow to the bottom surface of the reactor and from the bottom surface to the top surface of the TRIGA 2000 reactor. The method used in this practical work is the Computational Fluid Dynamics (CFD) Velocity method. CFD is a method for simulating fluid flow. The method is processed numerically and then digitally modeled. In practice, the authors modeled and studied the conceptual design of the reactor system using CFD based on Gambit and Fluent applications in a reactor tank. GAMBIT is an application produced by fluent inc. which is useful for making a model and discrete (meshing) to be analyzed by numerical methods. Fluent is an application that can solve fluid flow cases with the results obtained after discretizing the GAMBIT application. The results by CFD shows the distribution of fluid flow from the inlet pipe to the bottom surface of the reactor tank then the flow rises to the top surface to the outlet pipe. The velocity of the fluid flow from the inlet flow to the bottom surface was getting smaller, and the smallest value was at the bottom of the nuclear reactor, by 0.164 m/s and the flow distribution from the bottom surface to the top surface of the velocity value in a nuclear reactor would be bigger by the largest value being on the top surface of the nuclear reactor is 2.9 m/s.</em></p>2022-10-04T00:00:00+00:00Copyright (c) 2022