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A. Jannifar
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marzuki@pnl.ac.id
Phone
+6281337900427
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polimesin@pnl.ac.id
Editorial Address
Politeknik Negeri Lhokseumawe Jl. Banda Aceh-Medan Km. 280,3, Buketrata, Mesjid Punteut, Blang Mangat, Kota Lhokseumawe, 24301 Aceh, Indonesia
Location
Kota lhokseumawe,
Aceh
INDONESIA
Jurnal Polimesin
ISSN : 16935462     EISSN : 25491199     DOI : http://dx.doi.org/10.30811/jpl
Mechanical Engineering - Energy Conversion Engineering - Material Engineering - Manufacturing Technology - Mechatronics - Machine and Mechanism Design - Biomechanics
Articles 503 Documents
The effect of solar tracker movement on the thermal performance of solar cooker using the Fresnel lens solar concentrator Asrori Asrori; Sugeng Hadi Susilo; Kris Witono; Putu Wijaya Sunu
Jurnal POLIMESIN Vol 20, No 2 (2022): August
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v20i2.2652

Abstract

Solar energy as renewable energy has great potential to supply the world's energy needs. Solar thermal energy can be used for domestic energy purposes (cooking and water heating). The purpose of this research is to develop, design and analyze the performance of a solar cooker from the concentration of direct normal irradiance (DNI) by the Fresnel lens on the receiver/absorber as a cooking vessel. One form of improving the performance of the Fresnel solar concentrator (FSC) is the addition of an automatic solar tracker installation using hydraulic actuators. The solar tracker is varied, every 5 and 10 minutes, respectively. The solar cooker performance test was conducted outdoors at the Mechanical Engineering Department of State Polytechnic of Malang (7.9553 oS and 112.6125 oE) in April 2021. The method used actual experimental research. The measurement of solar radiation uses a solar power meter SPM-1116SD and the tracker's movement. At the same time, the temperature parameters (water temperature, receiver wall temperature, focal point temperature, ambient temperature) are measured by the temperature data logger. The concentrated solar cooker type design uses a fresnel lens with a capture area of 0.785 m2 and a focal ratio of 0.88. The main components of this solar cooker design consist of: a large fresnel lens that functions as a concentrator of sunrays, a cone-shaped cooking stove as a solar collector (receiver), and a hydraulic actuator-type solar tracker unit. Initial tests showed that the solar radiation, In = 789.00 W/m2, obtained the focal point temperature at the receiver, Tf = 930.10°C. Meanwhile, the thermal efficiency (Th) of a solar cooker with a solar tracker that moves every 10 minutes and 5 minutes is 12.7% and 33.66%, respectively. The increase in the thermal efficiency of the solar cooker is very significant, which is 2.65 times. This shows that the more accurate and continuous movement of the tracker will increase the thermal efficiency of the designed Fresnel solar cooker.
Implementation of PID Controller on Hohenheim Tunnel Dryer Using Ziegler-Nichols Approach Method Melinda Melinda; Rita Khatir; Ari Rahmat Putra Ibina; Alfatirta Mufti; Rizal Syahyadi; Iskandar Hasanuddin
Jurnal POLIMESIN Vol 21, No 1 (2023): February
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v21i1.3472

Abstract

Hohenheim Tunnel Dryer has two heating mechanisms, namely the solar collectors and the greenhouse effect. Two outlet fans are used to remove moisture from drying as well as to lower the temperature in the drying chamber. Suppose the outlet fans are turned on continuously, the temperature in the drying room will not reach the optimal drying temperature, and vice versa if the outlet fans are not turned on, the drying temperature can exceed 60°C. Controlling these outlet fans manually is a very inconvenient thing and becomes an obstacle for accepting this drying technology by the farmers. Therefore, this study focused on the design of temperature control for the Hohenheim Tunnel Dryer by using a proportional integral derivative (PID) controller with an Arduino Nano microcontroller. It controls the fan outlet to obtain an optimal drying temperature so that the operation of this dryer becomes more accessible and more efficient. The temperature sensor used is DHT22. The tuning method chosen is the Ziegler – Nichols method, and the setpoint value is selected at 55, which is the optimum temperature for drying most agricultural products. The design, manufacture, and testing of the temperature control system on the Hohenheim tunnel dryer was successfully carried out without over shoot and steady state error so it can be concluded that the system has worked well.
Kaji pemanfaataan energi matahari dengan teknik saluran belokan tajam muhamad haiyum
Jurnal POLIMESIN Vol 7, No 2 (2009): Agustus
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jop.v7i2.1383

Abstract

Pola aliran dalam  saluran  tersebut mempunyai suatu stuktur tiga dimensi  yang kompleks,  karena pemisahan aliran disebabkan oleh perubahan arah yang mendadak/tiba-tiba dari aliran di dalam belokan tajam lebih-lebih untuk  aliran   sekunder yang disebabkan oleh  gaya sentrifugal. Oleh karena  itu, laju perpindahan panas  konveksi lokal untuk penukaan daerah yang kecil diharapkan tingkat  perubaban secara nyala. Ukuran dari kolektor   adalah 250  cm x 80 cm.  Pada setiap  sisi dari kotak  absober  dilapisi  dengan  isolator  termal  berupa  karet  bewama  hitam   dengan  tebal  10 mm. Sebagai penyerap radiasi surya pada pengujian ini digunakan pasir besi dengan tebal 6 cm. Posisi kotak pemanas udara dibuat miring 150. Jumlah hambatan sebanyak sembilan buah. Pengukuran temperatur dilakukan dengan saluran  tanpa belokan,  saluran   multi belokan tajam 90°.   Pengujian   dilakukan    di   alam  terbuka  dengan  menggunakan   energi   surya  sebagai  energi pemanas dan pengukuran ternperatur dilakukan sebanyak  5  titk untuk saluran   tanpa hambatan dan  sebanyak 29 titik pada laluan aliran dengan hambatan. Pengujian dilakukan  dari jam 11.00 sampai  dengan   15.00   WIB.  Hasil   penelitian   menunjukan,   distribusi  temperatur   absorber  untuk ketiga   tipe  solar  kolektor   cenderung  sama,  distribusi    temperatur  tertinggi  dapat  dicapai    oleh kolektor    dengan  belokan   tajam  sudut  hambatan  90° yaitu  temperatur   maksimum   81    C pada waktu pukul 12.30-     13.30.Kata kunci  :   Kolektor  surya, saluran multi belokan,  hambatan,  absober
Effect of seawater flow velocity in South Malang on the corrosion rate of low carbon steel with a corrosion coupon rack Suprapto, Agus; Irwandi, Jul Viansyah Dwiki; Jumiadi, Jumiadi; Tsamroh, Dewi Izzatus
Jurnal Polimesin Vol 22, No 2 (2024): April
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v22i2.4897

Abstract

Corrosion is a phenomenon of damage to metal that can be influenced by several factors, including environmental factors, namely pH, humidity, temperature, and impurity factors. Corrosion that occurs due to the flow of a fluid is known as erosion corrosion. One type of metal that is susceptible to corrosion is carbon steel. Carbon steel material is very commonly used in the industrial world. An application of carbon steel is in piping systems that transport fluids; thus, fluid flow velocity affects the corrosion resistance of carbon steel. This research aimed to determine the effect of seawater flow on the corrosion rate of low carbon steel (ST 37) with variations in seawater velocity. This research is a type of laboratory-scale experimental research using coupon rack corrosion test equipment. The variations in seawater velocity used are 0 L/min, 15 L/min, 20 L/min, and 25 L/min. Observations of each experiment were carried out every 6 and 12 hours. The corrosion rate was analyzed using the weight loss method, namely by calculating the initial and final weight of the specimen before and after the experiment. The results show that increasing seawater flow velocity also increases the corrosion rate on steel specimens, with the lowest corrosion rate at 10.262 mpy on specimens with a variation of 0 L/min, while the highest corrosion rate is 48.743 mpy on specimens with a variation of 25 L/min. It can be concluded that the velocity of the fluid flow and the type of particles contained in the flow affect the rate of erosion-corrosion. The higher the fluid flow velocity and the more abrasive the particles contained in the flow, the faster the rate of erosion-corrosion.
Evaluation of Tubing Diameter and Bean Size for Optimization of Well Production Rate Arya Dwi Candra; Muhammad Firmansyah Hafidzullah; Rakha Reswara; Paradongan Siahaan; Dies Elita Budiyanti; Zainal Abidin
Jurnal POLIMESIN Vol 21, No 1 (2023): February
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v21i1.3196

Abstract

Gas field development is a costly affair, thus it is essential that each component of the production system operates properly. The objective of field optimization is to discover the parameter range that maximizes productivity. In addition, the development of natural gas reserves for both fuel and petrochemical purposes is accelerating. Well X is an approximately 4-year-old natural-flow gas well with a gas flowrate of 7.7 MMSCF/D, condensate flowrate of 55 BCPD, and water flowrate of 2 BWPD. As fluid is generated from the reservoir to the surface, the production rate of the well decreases. This well's productivity was evaluated using nodal analysis in conjunction with a comparison of tubing size and bean size. aiming to satisfy gas demand without exceeding the critical limit. The nodal analysis approach is utilized to determine the well's optimal and efficient performance. Moreover, utilizing system analysis, which is a graphical plot between the tubing size and the resulting flow rate, as depicted in Figure 6, we can determine which tubing size delivers the highest or most efficient rate at a particular moment under constant wellhead pressure (node at the wellhead). If the demand grows by 14.4 MMSCF/D, the installed tube size can be changed to 40/64" for optimization purposes. This procedure is more cost-effective because it does not squander money and does not halt gas production at the well. To satisfy the increased gas demand of 14.4 MMSCF/D, the production operator can rotate the bean or choke from its initial 24/64" size to 40/64" size.
Hardening of bucket teeth made from creusabro 8000 steel by using the induction hardening method Darma Firmansyah Undayat; Cecep Ruskandi; Ari Siswanto
Jurnal POLIMESIN Vol 21, No 3 (2023): June
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v21i3.3672

Abstract

Excavators are often used in mining projects such as for penetrating, excavating, dredging, gouging, and crushing mineral rocks. Bucket teeth are an excavator component that is often being replaced due to failure. The most common failure mode that occurred in bucket teeth was wear on the tip or front section of it. To reduce the wear of the bucket teeth material then its hardness should be increased. As the hardness value increases, the resistance to wear increases. The bucket teeth were made of Creusabro 8000 steel and a hardening process was then carried out on the front section of the bucket teeth components by using an induction furnace. The power used in the induction furnace varies from 28, 35, 42 and 49 kW (kilowatts) and the holding time varies between 3 and 5 minutes. The heat treatment process used oil as a cooling medium. The analysis was carried out to determine the area that experienced an increase in hardness and its occurred microstructure. Microstructure examination was carried out with an optical microscope, and hardness test by using a Vickers microscopy. It can be concluded from the result of the analysis that the large area experienced an hardness increase is directly proportional to the electric current magnitude and holding time. The microstructure has changed from fine pearlite to martensite thus hardness of Bucket Teeth can be increased up to 100% of the initial hardness.
Pengaruh temperature dengan konsentrasi elektrolit terhadap hasil elektroplating tembaga pada baja karbon rendah. Muhammad AB; Rudi Kurniawan
Jurnal POLIMESIN Vol 3, No 2 (2005): Agustus
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v3i2.1452

Abstract

Aplikasi teknik manufaktur vacuum assested resin infusion (vari) untuk peningkatan sifat mekanik komposit plastik berpenguat serat abaca (AFRP) Abubakar Dabet; Indra Indra; Teuku Hafli
Jurnal POLIMESIN Vol 16, No 1 (2018): Februari
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v16i1.551

Abstract

AbstrakInovasi dalam bidang material komposit menuntut terciptanya material yang lebih ramah lingkungan.  Saat ini komposit serat alam (green material) patut dipertimbangkan menjadi material yang sangat berpotensi untuk mensubstitusi komposit serat sintetis sebagai material teknik. Serat alam mempunyai kekurangan karena mempunyai scatter sifat mekanik yang sangat besar. Salah satu cara untuk mengatasi kekurangan tersebut adalah melalui pemilihan proses manufaktur (fabrikasi) komposit. Tujuan penelitian ini adalah membuat prototype komposit plastik berpenguat serat abaca (AFRP)  menggunakan metode Vakum (Vacum Assested Resin Infusion (VARI)). Semua spesimen dilakukan postcure pada suhu 800 C selama 2 jam. Sifat mekanik dari komposit dievaluasi uji tariknya. Komposit AFRP difabrikasi dengan fraksi volume (Vf) : 20%, 30% , 40%, serta ukuran spesimen uji (140x5x1) mm. Dengan proses fabrikasi sebagai berikut: 1) Serat abaca disusun dalam cetakan kaca yang memanjang sejajar (00) kemudian dimasukkan ke dalam kantong plastik vakum. 2) Resin dicampur hardener dialirkan kedalam cetakan yang sudah kondisi vakum. Metode cetakan ini dapat menghilangkan gelembung udara di dalam komposit sehingga diharapkan kekuatan tarik komposit menjadi lebih tinggi.  Bahan-bahan yang diperlukan dalam penelitian ini adalah: Serat abaca, Resin BTQN 157-EX, Hardener MEKPO dan Wax. Peralatan yang diperlukan adalah: Instalasi cetak vakum, Alat uji tarik, Kamera digital, dan Scanning Electron Microscope (SEM). Penampang patahan diselidiki untuk mengidentifikasi mekanisme perpatahannya.  Hasil penelitian menunjukkan bahwa kekuatan dan regangan tarik komposit memiliki harga optimum untuk (Vf) 40%, yaitu 257 Mpa dan 0.44%.  Penampang patahan komposit diklasifikasikan sebagai jenis patah slitting in multiple area sehingga dapat disimpulkan bahwa komposit plastik berpenguat serat abaca memiliki potensi yang cukup besar untuk diaplikasikan sebagai material struktural. Kata kunci: Serat Abaca, AFRP, Kekuatan tarik, VARI, Scanning Electron Microscope AbstractInnovation in composite materials demands the creation of more environmentally friendly materials. Currently the composite of natural fibers (green material) should be considered to be a material that has the potential to substitute synthetic fiber composites as engineering materials. Natural fibers have disadvantages because they have a very large mechanical properties scatter. One way to overcome these shortcomings is through the selection of a composite manufacturing (fabrication) process. The purpose of this research is to make prototype of plastic composite with abaca fiber (AFRP) using Vacuum Assured Resin Infusion (VARI)). All specimens were performed postcure at 800 C for 2 hours. The mechanical properties of the composites are evaluated by the tensile test. The AFRP composite is fabricated by volume fraction (Vf): 20%, 30%, 40%, as well as test specimen size (140x5x1) mm. With the fabrication process as follows: 1) Abaca fiber is arranged in a parallel laminated glass mold (00) then put in a vacuum plastic bag. 2) The resin in the mixed hardener flowed into a mold that has a vacuum condition. This mold method can remove air bubbles inside the composite so that the expected composite tensile strength becomes higher. The materials needed in this research are: Abaca fiber, BTQN 157-EX Resin, MEKPO and Wax Hardener. The necessary equipment are: Vacuum printing installation, Tensile test equipment, Digital camera, and Scanning Electron Microscope (SEM). Fault cross sections were investigated to identify the fracture mechanism. The results showed that the strength and composite tensile strain had the optimum price for (Vf) 40%, ie 257 Mpa and 0.44%. The composite fault cross section is classified as a type of broken slitting in multiple areas so it can be concluded that the plastic composite of abaca fibers has considerable potential to be applied as a structural material. Keywords: Abaca Fiber, AFRP, Tensile Strength, VARI, Scanning Electron Microscope
Designing of Evaporator Length in Very Low Temperature Chest Freezer by using Environmentally Friendly Refrigerant R290 Sumeru, Kasni; Nugraha, Ridwan; Badarudin, Apip; Simbolon, Luga Martin; bin Sukri, Mohamad Firdaus; Yuningsih, Nani
Jurnal Polimesin Vol 21, No 5 (2023): October
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v21i5.4103

Abstract

Chest freezers generally use R600a or R134a as working fluids. When using R600a, the minimum cabin temperature is only -10oC, whereas when using R134a, it can reach -25oC. The purpose of this study is to calculate the evaporator length of a chest freezer that uses R290 as a refrigerant so that its cabin temperature can reach below 35 oC, lower than the cabin temperature of a typical chest freezer. Calculation of the evaporator pipe length is done using the forced convection heat transfer equation to calculate the heat transfer coefficient inside the evaporator pipe and natural heat transfer to calculate the heat transfer coefficient outside the evaporator pipe.  Based on the calculations, the chest freezer has a compressor capacity of 200 W, an evaporator length of 3.57 m, and a diameter of 3/8 inch or 9.52 mm. The test results show that the temperature of the chest freezer cabin can reach -36oC in the 36th minute with a cooling capacity of 289 W, while the input power and COP are 198 watts and 1.46, respectively. Compared to R134a, the use of R290 is more advantageous. In addition to lower cabin temperatures, it is also much more environmentally friendly, because the GWP (global warming potential) value of R134a is much higher than that of R290. It means that the use of R290 as a working fluid in the chest freezer will significantly reduce emissions of gases that cause global warming.
Review Of Multicrystalline Silicon Wafer Solar Cell Processing Azwar Azwar; Luthfi Luthfi; Muhammad Muhammad
Jurnal POLIMESIN Vol 19, No 1 (2021): February
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v19i1.2090

Abstract

The challenges for searching and utilizing  of new and sustainable energy sources especially solar cell electricity. The major obstacle of using solar cells for electricity generation has been a much higher price when compared to the price of electricity generated from the traditional sources. The photovoltaic industry needs to put an enormous pressure and optimization at every stage of the photovoltaic manufacturing chain of multicrystalline silicon wafer solar cell processing  in order to reduce cost.  Processing of multicrystalline silicon solar cells  is starting by silicon wafer preparation, etching and texturing,  saw damage etching, surface texturing, phosphor diffusion edge isolation, phosphor diffusion, edge isolation, silicon nitride deposition for antireflection coating, and metallization process that consist of screen printing ag front side, screen printing of al back side, drying and firing and formation al back surface contact.  Mechanical stability of silicon wafer became a serious issue due to reduction of wafer thickness, so probability for wafer to breakage is high; investigate the mechanism of wafer breakage is important to reduce breakage. The present of micro cracks reduces the mechanical strength of wafer significantly and wafer breakage will increase, because crack will start from the existing micro crack and that will propagate easier with presence of the stress. Mechanical stability is increase significantly after the etching process; on the other hand the screen printing process will reduce wafer strength.  Etching of saw damage, that is induced during wafer slicing, and metallization of the surfaces are 2 crucial processing steps in the manufacturing of mc-silicon solar cells

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