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All Journal Rotasi Journal of Mechanical Engineering Science and Technology Turbo : Jurnal Program Studi Teknik Mesin Otopro Jurnal Pendidikan Teknik Mesin Undiksha Community Development Journal: Jurnal Pengabdian Masyarakat Reswara: Jurnal Pengabdian Kepada Masyarakat AEEJ : Journal of Automotive Engineering and Vocational Education Jurnal Pengabdian Multidisiplin Indonesian Community Journal Jurnal Hilirisasi Technology kepada Masyarakat (SITECHMAS) Jurnal Pepadu RING Mechanical Engineering GEMBIRA (Pengabdian Kepada Masyarakat) Jurnal Polimesin Evrimata: Journal of Mechanical Engineering
Monasari, Ratna
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Pengaruh Penambahan Zat Aditif Pada Campuran Bahan Bakar Bensin – Bioethanol Terhadap Specific Fuel Consumption Monasari, Ratna; Firdaus, Ahmad Hanif; Qosim, Nanang
Jurnal Pendidikan Teknik Mesin Undiksha Vol. 9 No. 1 (2021)
Publisher : UNIVERSITAS PENDIDIKAN GANESHA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jptm.v9i1.31797

Abstract

Pemanfaatan energi terbarukan di Indonesia masih tergolong rendah dibandingkan dengan sumber energi tak terbarukan dari minyak bumi, batu bara, maupun gas alam. Dengan jumlah energi tak terbarukan yang terbatas mendorong untuk mengembangkan penggunaan bahan bakar alternatif. Saat ini bioetanol merupakan salah satu bahan bakar alternatif yang sedang dikembangkan sebagai pengganti maupun campuran bahan bakar bensin, yang dikenal sebagai etanol anhidrat yang memiliki konsentrasi diatas 96%. Campuran bioetanol memberikan pengaruh terhadap peningkatan bilangan oktan dan mampu mengurangi emisi gas buang yang dihasilkan. Untuk mendapatkan efek yang lebih optimal dalam konsumsi bahan bakar zat aditif seperti oxygenated cyclohexanol ditambahkan pada campuran bahan bakar. Studi dilakukan pada perbandingan bahan bakar E5 sampai E15 dengan penggunaan aditif tersebut. Pengujian konsumsi bahan bakar dilakukan pada mesin satu silinder spark ignition dengan posisi bukaan throttle 100%. Terdapat sensor pada bagian tanki bahan bakar untuk menghitung specific fuel consumption (SFC) dengan variasi kecepatan mesin. Penelitian ini bertujuan untuk melihat pengaruh penambahan zat aditif pada campuran bahan bakar terhadap konsumsi bahan bakar.Kata kunci: bensin; bioetanol; emisi gas buang; zat aditif.The use of renewable energy in Indonesia is still low compared to non-renewable energy sources from petroleum, coal, and natural gas. The limited amount of non-renewable energy encourages developing the use of alternative fuels. Currently, bioethanol is an alternative fuel that is being developed as a substitute or mixture of gasoline fuel, known as anhydrous ethanol which has a concentration above 96%. The bioethanol mixture has an effect on increasing the octane number and is able to reduce the resulting exhaust gas emissions. To get a more optimal effect on fuel consumption, additives such as oxygenated cyclohexanol are added to the fuel mixture. Studies were carried out on the comparison of fuel E5 to E15 with the use of these additives. The fuel consumption test was carried out on a single-cylinder spark-ignition engine with a 100% throttle opening position. There is a sensor on the fuel tank to calculate the specific fuel consumption (SFC) with variations in engine speed. This study aims to determine the effect of adding additives to the fuel mixture on fuel consumption.Keywords : fuel; bioethanol; exhaust gas emissions; additives. DAFTAR RUJUKANAbikusna, S., Sugiarto, B., & Suntoro D. (2017). Low Grade Bioethanol for Fuel Mixing on Gasoline Engine Using Distillation Process. in AIP Conference Proceedings. AIP Publishing.Abikusna, S. (2018). The Effect of Additive on Combustion Characteristics and Cycle to Cycle Variations on SI Engine Fueled by Gasoline and Bioethanol, Technology organic and inorganic substances. P. 27-37. Doi: 10.15587/1729-4061.2018.147585Abikusna, S., B. Sugiarto, & Zulfan, A. (2017). Fuel consumption and emission on fuel mixer low-grade bioethanol fuelled motorcycle. in MATEC Web of Conferences. EDP Sciences.Costa, R. C., &  Sodré, J.R.  (2011). Compression ratio effects on an ethanol/gasoline fuelled engine performance. Applied Thermal Engineering, 31(2): p. 278-283.de Melo, T.C.C., et al., 2012. Hydrous ethanol–gasoline blends–Combustion and emission investigations on a Flex-Fuel engine. Fuel, 97: p. 796-804.Costa, R.C. & Sodré, J.R. (2009) . Hydrous Ethanol Vs. Gasoline-Ethanol Blend: Engine Performance and Emissions. International Journal of FuelGao, J. D. J., &  Huang, Z. (2007). Spray Properties of Alternative Fuels: A Comparative Analysis of Ethanol–Gasoline Blends and Gasoline. Fuel. 86(10): p. 1645-1650.Keith, O., & Trevor, C. (1995). Automotive fuels reference book. Society of Automotive Engineers, Inc. Warrendale,  p. 487.Gholamhassan, N. B. G., Yusaf, T. Safieddin, S. M., & Ardebili, R.M. (2015). Optimization of performance and exhaust emission parameters of a SI (spark ignition) engine with gasoline-ethanol blended fuels using response surface methodology. Elsevier, energy xxx: p. 15.Jang, S. H., & Choi, J. H. (2016). Comparison of fuel consumption and emission characteristics of various marine heavy fuel additives. Applied Energy, 179, 36–44. https://doi.org/10.1016/j.apenergy.2016.06.122Monasari, R., Abikusna, S., Sugiarto, B., & Ajiseno, B. (2018). IOP Conference Series: Earth and Environmental Science Analysis of emission gas and fuel consumption on SI engine fueled with low-grade bioethanol and oxygenated cycloheptanol additive Analysis of emission gas and fuel consumption on SI engine fueled with low-grade bioethanol and oxygenated cycloheptanol additive. 105, 12058. https://doi.org/10.1088/1755-1315/105/1/012058Srinivasan, C. A., &  Saravanan, C. (2010). Study of Combustion Characteristics of an SI Engine Fuelled with Ethanol and Oxygenated Fuel Additives. Journal of Sustainable Energy & Environment. 1(2): p. 85-91.Sugiarto, B. (2002) Motor Pembakaran Dalam. Jakarta: Universitas Indonesia. ISBN 979- 97726-7-2.Thangavelu, S. K., Ahmed, A. S., & Ani, F. N. (2016). Review on Bioethanol as Alternative Fuel for Spark Ignition Engines. Renewable and Sustainable Energy Reviews. 56: p. 820-835Zhao, L., Wang, X., Wang, D., & Su, X. (2020). Investigation of the effects of lean mixtures on combustion and particulate emissions in a DISI engine fueled with bioethanol-gasoline blends. Fuel, 260, 116096. https://doi.org/10.1016/j.fuel.2019.116096
MONITORING PADA UNIT GRADER 825A-2 DENGAN ALAT DATA LOGGER BERBASIS INTERNET OF THINGS PT KALIMANTAN PRIMA PERSADA JOBSITE INDE Pratama, Argiansyah Bayu; Monasari, Ratna; Khambali, Khambali; Pratama, Rizki Priya
TURBO [Tulisan Riset Berbasis Online] Vol 14, No 1 (2025): TURBO : Jurnal Program Studi Teknik Mesin
Publisher : Universitas Muhammadiyah Metro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24127/trb.v14i1.4145

Abstract

The GD825A-2 Grader Unit at PT Kalimantan Prima Persada Jobsite Indehas an average Physical Availability (PA) value of 89%, below the target of 92%, due to the high unscheduled breakdown. Manual monitoring of sensor parameters is one of the causes of delays in damage detection. This study designs and implements an Internet of Things (IoT)-based monitoring tool with a data logger to read sensor data in real-time. The methods used include testing sensor accuracy against manual measuring instruments, descriptive statistical analysis, errors, and process capability tests. The results show a temperature sensor error rate of 2%, oil pressure 5%, and engine rotation 0.11%. All sensors are also proven to be stable, within statistical control limits, and have decent process capabilities. This system allows for accurate, fast, and remote monitoring of unit conditions, thereby reducing the risk of breakdown, and optimizing maintenance costs for the GD825A-2 unit.
Pengaruh Ukuran Venturi dan Rasio Kompresi Terhadap Torsi dan SFC Motor Bensin 2 Langkah 149 cc Monasari, Ratna; Fatazar, Iqbal Irza
AEEJ : Journal of Automotive Engineering and Vocational Education Vol 5 No 1 (2024): AEEJ : Journal of Automotive Engineering and Vocational Education
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/aeej.v5i1.238

Abstract

Most motorbike users desire enhanced engine performance beyond the usual level. Typically, users of 2-stroke motorcycles enhance engine performance by modifying the diameter of the carburetor venture and adjusting the compression ratio. This study employs an experimental approach to investigate the impact of alterations in venturi size and compression ratio on the performance of a 2-stroke petrol motorcycle. Torque measurements are obtained using a dynamometer, whereas fuel consumption measurements are obtained using a burette. Subsequently, the generated results are utilized as graphical representations for analysis. Based on the findings of torque research, the utilization of a venturi diameter of 29 mm coupled with a compression ratio of 7.5:1 demonstrates the most significant enhancement in torque. Meanwhile, the findings of the SFC research indicate that using a venturi diameter of 28 mm and a compression ratio of 7.5:1 yields the lowest value. Sebagian besar pengguna sepeda motor menginginkan kinerja mesin yang lebih baik daripada kinerja mesin standar. Pada umumnya pengguna motor 2 langkah untuk meningkatkan kinerja mesin melakukan perubahan pada diameter venturi karburator dan rasio kompresi. Penelitian ini menggunakan metode eksperimental yang bertujuan untuk mengetahui perubahan ukuran venturi dan rasio kompresi terhadap kinerja motor bensin 2 langkah. Pemgambilan data torsi menggunakan alat dynamometer sedangkan pengambilan data konsumsi bahan bakar menggunakan alat buret. Kemudian hasil yang diperoleh dijadikan grafik untuk dilakukan analisis. Mengacu pada pada hasil penelitian torsi, penggunaan diameter venturi 29 mm dengan rasio kompresi 7,5 : 1 menunjukkan peningkatan torsi paling tinggi. Sedangkan pada hasil penelitian SFC, penggunaan diameter venturi 28 mm dengan rasio kompresi 7,5 : 1 menunjukkan nilai paling rendah.
Transformasi Digitalisasi Manajemen Keuangan dan Peningkatan Kapasitas Produksi UMKM Pie Ngalam Heritage melalui Program Pelatihan Berbasis Mitra Farida, Nike Nur; Putra, Agus Dwi; Monasari, Ratna; Susanto, Susanto; Afifa, Ulfiana Ihda
I-Com: Indonesian Community Journal Vol 5 No 3 (2025): I-Com: Indonesian Community Journal (September 2025)
Publisher : Fakultas Sains Dan Teknologi, Universitas Raden Rahmat Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.70609/i-com.v5i3.8045

Abstract

UMKM berperan penting dalam perekonomian, namun masih terkendala pada pencatatan keuangan sederhana dan keterbatasan kapasitas produksi. Program pengabdian ini dilaksanakan pada UMKM Pie Ngalam Heritage melalui dua tahap, yaitu pelatihan digitalisasi pencatatan keuangan dan akuntansi dasar (11–13 Agustus 2025), serta pelatihan peningkatan kapasitas produksi menggunakan dough mixer kapasitas besar (6–9 September 2025). Metode kegiatan meliputi workshop interaktif, demonstrasi teknis, dan pendampingan. Hasil menunjukkan mitra mampu menerapkan pencatatan keuangan digital, menyusun laporan bulanan, dan memahami akuntansi dasar. Kapasitas produksi meningkat dari 70 pie/hari menjadi 250 pie/hari, atau naik sekitar 257%, dengan mutu lebih konsisten, sementara strategi pemasaran digital dan roadmap bisnis tersusun lebih terarah. Kegiatan ini berhasil meningkatkan daya saing UMKM serta mendukung pencapaian SDGs poin 8 dan IKU perguruan tinggi vokasi.
UPAYA PENURUNAN POTENSI KERAWANAN LINGKUNGAN MELALUI PEMASANGAN PAGAR PENGAMAN DI DESA NGENEP KEC. KARANGPLOSO KAB. MALANG Nurhadi, Nurhadi; Walid, Achmad; Farida, Nike Nur; Monasari, Ratna; Aji, Supa Kusuma; Winoko, Yuniarto Agus
Jurnal Pepadu Vol 6 No 3 (2025): Jurnal Pepadu
Publisher : Universitas Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/pepadu.v6i3.7883

Abstract

RT 04 RW 16, Ngenep Village, Karangploso District, Malang Regency faces environmental vulnerability due to a damaged security fence, allowing outsiders to enter and exit freely, increasing the risk of safety disturbances. This problem is worsened by the fact that the housing estate management was abandoned after the developer was declared bankrupt, forcing residents to manage the environment independently. This situation raises concerns about neighborhood security and urges the need for a concrete, collective solution to mitigate the issue. This community service activity aims to reduce environmental vulnerability by designing and constructing a permanent safety fence in a vacant lot prone to security risks as a preventive measure to enhance neighborhood safety. The methods include analyzing the partner's problems, determining priority issues, designing the fence using AutoCAD, and constructing a 7 x 3.25-meter fence consisting of stone foundations, cast pillars, and lightweight brick walls. The results showed that the safety fence was successfully installed as planned, serving as a physical barrier that limits outsider access, enhances residents' sense of security, and fosters community awareness regarding environmental safety. An evaluation of the project revealed a cost efficiency of 17% compared to the initial Budget Plan (RAB). This activity is expected to serve as a practical solution model for other areas facing similar challenges in community-based environmental security management. Moreover, this project has had a positive impact by increasing community solidarity and encouraging a spirit of mutual cooperation among residents to protect their neighborhood environment.
Effect of turbo cyclone vane angles on performance and emissions of a 1000 cc engine Monasari, Ratna; Qosim, Nanang; Jaya, Kukuh Laksana; Pratama, Argiansyah Bayu
Jurnal Polimesin Vol 23, No 4 (2025): August
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v23i4.7075

Abstract

The installation of a turbo cyclone in the intake manifold aims to increase airflow turbulence, thereby improving the air–fuel mixture process inside the combustion chamber. This study investigates the effects of turbo cyclone implementation on the performance, fuel consumption, and exhaust emissions of a 1000 cc engine. The cyclone was designed with six fixed vanes at angles of 30°, 45°, and 60°, and tested using two fuels: RON 90 and RON 92. Engine performance was measured with a dynamometer across 1000–6000 rpm, fuel consumption was evaluated using Specific Fuel Consumption (SFC), and exhaust emissions were analyzed with a gas analyzer. Results indicate that the 60° vane angle delivers the best overall performance, achieving a maximum power of 34.1 HP, peak torque of 57.4 Nm, and the lowest SFC of 93.33 g/kWh. Additionally, CO and HC emissions were reduced by up to 40% compared to the baseline (non-cyclone) condition. Among the tested fuels, RON 92 consistently provided better performance and lower emissions, highlighting its higher combustion efficiency. These findings demonstrate that the turbo cyclone (particularly at a 60° vane angle) effectively improves engine efficiency, enhances output, and reduces harmful emissions.
UPAYA PENINGKATAN PRODUKTIVITAS UMKM HASIM FURNI SIDOARJO MELALUI MODIFIKASI MESIN AMPLAS KAYU Mufarrih, AM.; Rohman, Fatkhur; Monasari, Ratna; Amrullah, Utsman Syah; Hartono, Moh.
Community Development Journal : Jurnal Pengabdian Masyarakat Vol. 5 No. 5 (2024): Vol. 5 No. 5 Tahun 2024
Publisher : Universitas Pahlawan Tuanku Tambusai

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31004/cdj.v5i5.35608

Abstract

UMKM Hasim Furni adalah salah satu industri kerajinan kayu di Kabupaten Sidoarjo yang bergerak di bidang manufaktur furniture setengah jadi, khususnya dalam pembuatan kaki-kaki kursi, kaki-kaki lemari, kaki-kaki meja, dan hiasan lain untuk pesanan perusahaan manufaktur furniture. Proses produksi furnitur setengah jadi tidak terlepas dari tahap pengamplasan. Ketidaknyamanan posisi kerja memperlambat penyelesaian pekerjaan, yang pada akhirnya mengurangi produktivitas mesin amplas kayu. PPM ini dilakukan untuk memodifikasi mesin amplas kayu supaya lebih produktif dan nyaman digunakan. Metode penyelesaiannya meliputi; survey lapangan, analisis ergonomis menggunakan RULA, modifikasi mesin amplas kayu, pemasangan mesin amplas kayu hasil modifikasi, pembuatan SOP pengoperasian mesin amplas kayu, dan pelatihan penggunaan mesin amplas kayu. Hasil modifikasi mesin amplas kayu ini berhasil membuat posisi kerja yang nyaman sehingga produktivitas kerja dan kapasitas produksi meningkat. Analisis ergonomis menggunakan RULA dijadikan referensi untuk menentukan dimensi mesin amplas yang dirancang. Aspek ergonomi dipertimbangkan dalam perancangan fasilitas dan lingkungan kerja agar lebih efektif dan nyaman, sehingga produktivitas dapat meningkat.
STUDI PENGGUNAAN MANIPULATOR TEGANGAN PADA SENSOR TEKANAN BAHAN BAKAR MESIN DIESEL COMMON RAIL DITINJAU DARI DAYA & KONSUMSI BAHAN BAKAR Farida, Nike Nur; Monasari, Ratna; Gunawan, Chandra; Aji, Supa K.
Otopro Vol 19 No 2 Mei 2024
Publisher : Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/otopro.v19n2.p71-77

Abstract

In a common rail diesel engine system, the entire fuel system is regulated electronically by a computer device called the ECU.  With this sensor manipulator tool, it is hoped that you will be able to change the output of the fuel pressure sensor to modify the ECU input. This makes it possible to change the power produced by the vehicle and reduce fuel consumption. This research is using experimental methods. The initial step is to take vehicle power test data under normal conditions, with the fuel pressure sensor output voltage at 1.28 V, reduced by 0.2 (1.08 volts), decreased by 0.1 (1.18 volts), increased by 0,1 (1.38 volts), and up 0.2 (1.48 volts). The results of this research show that the highest power at a speed of 80 km/h occurs at a voltage of 1.38 volts and 1.48 volts, with a power of 103 HP. Optimal fuel pressure produces good misting, ensures the mixture of fuel and air in the combustion chamber is homogeneous, and produces maximum power. The results of the fuel consumption test show that the lowest fuel consumption occurs at a vehicle speed of 40 km/hour with a fuel pressure sensor voltage of 1.38 volts, which is around 0.615 cc/second. It can be concluded that a voltage of 1.38 volts produces the most optimal fuel pressure. The throttle valve and pedal openings are still slightly open, so the amount of fuel entering the combustion chamber is also limited, so fuel consumption is very economical.
THE The Effect of Mixing Plastic Pyrolysis Oil with Pertamax and Variation Of Ignition Timing on Performance and Emissions Naufal Hana Rizqullah; Monasari, Ratna; Utami Handayani, Sri; Aditya, Candra
Evrimata: Journal of Mechanical Engineering Vol. 01 No. 01, 2024
Publisher : PT. ELSHAD TECHNOLOGY INDONESIA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.70822/evrmata.vi.18

Abstract

One source of energy that has not been utilized optimally is waste. One of the abundant waste materials is plastic waste. Processing plastic waste in the form of plastic pyrolysis oil affects the performance and emissions of motor vehicles when mixed with Pertamax fuel, as well as variations in ignition timing. The purpose of this research is to determine the influence of changes in ignition timing on engine power, as well as to investigate the impact of using Pertamax mixed with pyrolysis fuel results on engine power. The fuel mixture is prepared based on volume ratios (0%, 10%, 20%, 30%, 100%) of pyrolysis to gasoline, with engine speeds ranging from 6500 to 9000 rpm. The experiment results, when the ignition timing was set at 6⁰, 8⁰, and 10⁰, there was a slight decrease in power and less stable results in some engine speed.
EPOKSIDASI MINYAK JARAK JATROPHA CURCAS L. UNTUK MENINGKATKAN STABILITAS DAN PERFORMA PELUMAS NABATI RAMAH LINGKUNGAN Agus Dwi Putra; Farida, Nike Nur; Monasari, Ratna; Rakhmaddian, Nicko Nur; Fadhilah, Intan; Prasetyo, Heru
RING ME Vol 5 No 2 (2025): RING Mechanical Engineering
Publisher : Universitas Islam Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33474/rme.v5i2.24145

Abstract

The decline of petroleum reserves and environmental issues from petroleum-based lubricants have driven interest in biolubricants. Jatropha curcas L. oil is a promising candidate due to its availability and non-edible nature, but it lacks sufficient oxidative stability and thermal performance. This study aims to improve jatropha oil quality through in situ epoxidation. The research included oil extraction, initial chemical analysis (acid value, moisture, saponification value, iodine value), epoxidation with varied reactant ratios and reaction times, and post-modification tests of viscosity and flash point. Results indicated that oil yield from dehulled seeds was higher (60%) than hulled seeds (25%). Epoxidation improved viscosity from 2.39 cSt to 34.2 cSt at 40°C and raised the flash point from 109°C to 270°C. These enhancements demonstrate improved physicochemical properties, making epoxidized jatropha oil a potential eco-friendly lubricant comparable to modern synthetic lubricants.
Co-Authors Abikusna, Setia Afifa, Ulfiana Ihda Agus Dwi Putra Ahmad Hanif Firdaus Aini, Fica Aida Nadhifatul Aji , Supa Kusuma Aji, Supa K. Aji, Supa Kusuma Akhlis Rizza, Muhammad AM Mufarrih Amalia, Zakiyah Amrullah, Radhi Nurvian Amrullah, Utsman Syah Anggit Murdani Astuti, Fina Andika Frida Candra Aditya Dharsono, Ekky Yovianto Emzain, Zakki F Etik Puspitasari, Etik Farida, Nike Nur fatazar, iqbal irza Fatkhur Rohman Gunawan, Chandra Intan Fadhilah, Intan Jaya, Kukuh Laksana Khaerudin, Dian Noorvy Khambali, Khambali Kurniawan, Alfian Seina Lisa Agustriyana Moh. Hartono N. R., Siti Duratun Nanang Qosim Naufal Hana Rizqullah Nicko Nur Rakhmaddian, Nicko Nur Nila Alia Nurhadi Pratama, Argiansyah Bayu Putra, Agus Dwi Raharjo, Nain D Rizki Priya Pratama, Rizki Priya Sri Utami Handayani Susanto Susanto Syamsiar, Syamsiar Talifatim Machfuroh, Talifatim Walid, Achmad Yanuar Mahfudz Safarudin Yuniarto Agus Winoko, Yuniarto Agus Zainuri, Ach. Muhib Zakki Fuadi Emzain