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PENGGUNAAN PARAFFIN WAX SEBAGAI PENYIMPAN KALOR PADA PEMANAS AIR TENAGA MATAHARI THERMOSYPHON Nadjib, Muhammad
ROTASI Vol 18, No 3 (2016): VOLUME 18, NOMOR 3, JULI 2016
Publisher : Departemen Teknik Mesin, Fakultas Teknik, Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (479.195 KB) | DOI: 10.14710/rotasi.18.3.76-85

Abstract

Pemanas Air Tenaga Matahari (PATM) konvensional umumnya menggunakan air sebagai penyimpan energi termal. Pemakaian sensible heat storage (SHS) ini memiliki kekurangan, diantaranya adalah densitas energinya rendah. Di sisi lain, latent heat storage (LHS) mempunyai sifat khas yaitu densitas energinya tinggi karena melibatkan perubahan fasa dalam penyerapan atau pelepasan kalor. Material LHS sering disebut phase change material (PCM). Penggunaan PCM pada PATM menarik dilakukan untuk meningkatkan densitas energi sistem. Penelitian ini bertujuan untuk menyelidiki perilaku termal penggunaan paraffin wax di dalam tangki PATM jenis thermosyphon. Penelitian menggunakan kolektor matahari pelat datar dan tangki thermal energy storage (TES) yang dipasang secara horisontal di sisi atas kolektor. Di dalam tangki terdapat alat penukar kalor yang terdiri dari sekumpulan pipa kapsul dimana di dalamnya berisi paraffin wax. Air digunakan sebagai SHS dan heat transfer fluid (HTF). Termokopel dipasang di sisi HTF dan sisi PCM. Piranometer dan sensor temperatur udara luar diletakkan di dekat kolektor matahari. Pengambilan data dilakukan selama proses charging. Temperatur HTF, PCM dan intensitas radiasi matahari direkam setiap 30 detik. Data ini digunakan untuk mengetahui evolusi temperatur HTF dan PCM. Berdasarkan evolusi temperatur ini kemudian dianalisis perilaku termal PATM. Hasil dari penelitian ini adalah bahwa paraffin wax telah berfungsi sebagai penyimpan energi termal bersama air di dalam tangki PATM jenis thermosyphon. PCM memberi kontribusi yang cukup signifikan terhadap kapasitas penyimpanan energi sistem. Efisiensi kolektor lebih optimal karena PCM dapat mempertahankan stratifikasi termal sampai akhir charging. Adanya PCM mampu mengendalikan penurunan efisiensi pengumpulan energi saat intensitas radiasi matahari menurun. Alat penukar kalor yang digunakan cukup efektif yang ditandai dengan kecepatan pemanasan rata-rata antara HTF dan PCM yang tidak berbeda jauh.
Unjuk Kerja Mesin Diesel Berbahan Bakar Campuran Biodiesel Jatropha- Jelantah 1:9 Wahyudi, Wahyudi; Nadjib, Muhammad; Aji, Yogi Purnomo
TURBO [Tulisan Riset Berbasis Online] Vol 12, No 2 (2023): TURBO: Jurnal Program Studi Teknik Mesin
Publisher : Universitas Muhammadiyah Metro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24127/trb.v12i2.2843

Abstract

In the context of a rapidly growing industry and increasing energy needs, the dwindling sources of fossil fuels prompt the necessity for alternative fuels. This study focuses on the performance of diesel engines running on a blended biodiesel made from jatropha oil and waste cooking oil in a 1:9 ratio. The aim of this study is to investigate the effects of biodiesel fuel made from jatropha oil and waste cooking oil on diesel engine performance and fuel physical properties. The tests include an evaluation of the fuels physical properties, injection characteristics, engine speed, generated power, and specific fuel consumption (SFC). Results indicate that although this blended biodiesel has higher density and viscosity compared to diesel, it offers promising calorific value and spray angle. Moreover, engines using this fuel showed relatively stable engine speeds and power outputs, along with efficient SFC at higher loads. The jatropha-waste cooking oil biodiesel blend shows potential as a sustainable and environmentally-friendly alternative fuel
Pembuatan Mesin Pengisian Botol Sirup Aloe Vera Low Budget di UKM SMK Muhammadiyah 2 Turi Yogyakarta Riyanta, Bambang; Kusuma Yudha, Fitroh Anugrah; Nadjib, Muhammad; Susetyorini, Jurit Tri
Humantech : Jurnal Ilmiah Multidisiplin Indonesia Vol. 1 No. 7 (2022): Humantech : Jurnal Ilmiah Multidisiplin Indonesia
Publisher : Program Studi Akuntansi IKOPIN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32670/ht.v1i7.1718

Abstract

Pengolahan sumber daya alam dengan pemanfaatan panen aloevera yang dilakukan UKM SMK Muhammadiyah 2 Turi dari penanaman bibit aloevera, masa panen aloevera serta pengolahan aloevera masih mempunyai permasalahan misalnya, pengelolahan aloevera sebagai minuman bergizi menjadi sirup dan dikemas kedalam botol, untuk pengisian mengalami permasalahan pertama dalam pengisian botol sirup masih terdapat takaran yang tidak sama antara botol satu dengan botol yang lainnya. Permasalahan yang kedua terdapat pada pengemasan tutup botol, dalam tutup botol yang dikerjakan secara manual akan menghabat untuk tercapainya target yang sesuai pesanan produk. Solusi untuk permasalahan tersebut Berdasarkan permasalahan mitra diatas, berikut ini adalah solusi yang ditawarkan dalam pengabdian masyarakat. Pertama pembuatan mesin pengisian botol yang bisa membantu produksi dengan harga mesin yang sederhana dan terjangkau dengan manajemen keuangan UKM SMK Muhammadiyah 2 Turi Yogyakarta, dengan harga yang terjangkau atau berkisar dibawah 2 juta. Untuk solusi yang kedua pembuatan alat bantu untuk pengemasan tutup botol yang bisa membantu produksi supaya produksi bisa sesuai dengan target yang ditentukan. Kegiatan pengabdian masyarakat ini direncanakan untuk pembuatan mesin pengisian volume cairan dalam botol, dengan hasil yang diinginkan dengan ukuran volume yang berbeda-beda yaitu 100ml, 200ml, 250ml, 300ml, dan 500ml, dan alat bantu penutup botol.
Study of UiO-66 and UiO-66 Modulated with Acetic Acid as the Adsorbent for Eriochrome Black T Dye Pambudi, M. Anugrah Rizky; Prayogo, Nanda; Nadjib, Muhammad; Ediati, Ratna
Indonesian Journal of Chemical Research Vol 8 No 3 (2021): Edition for January 2021
Publisher : Jurusan Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598/ijcr.2021.8-riz

Abstract

UiO-66, as one of the metal-organic framework (MOF) compounds, has been used to treat some anionic and cationic dye waste. In order to determine the adsorption selectivity decisively, the synthesis of UiO-66 and UiO-66 modulated with acetic acid had been carried out, along with their adsorption tests for Eriochrome Black T (EBT) dye solution. The synthesis was performed by utilizing a solvothermal method with the reaction mixtures of zirconium (IV) chloride (ZrCl4) and terephthalic acid (H2BDC) as a ligand heated at 120 oC for 24 hours. Both UiO-66 (without acetic acid) and acetic acid modulated UiO-66 were obtained as a white powder. Acetic acid as a modulator was added and being investigated for the adsorption capability compared to the normal UiO-66. This study showed that normal UiO-66 exhibited better adsorption than acetic acid modulated UiO-66 with a mmol ratio of acetic acid:ligand varied from 50:1, 100:1, and 150:1. Acetic acid modulated UiO-66 with a mmol ratio of 50 exhibited the best crystallinity as observed by using x-ray diffraction. It can be concluded that the adsorption of EBT using normal and acetic acid modulated UiO-66 obeyed the pseudo-second-order reaction rate law as well as the Langmuir adsorption isotherm pattern.
Thermal Stratification Characteristics of Storage Tanks on Solar Water Heater Inserted with Latent Heat Material Nadjib, Muhammad; Wahyudi, Wahyudi; Santosa, Tito Hadji Agung; Hidayat, Yaafi
Semesta Teknika Vol 27, No 1 (2024): MEI
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/st.v27i1.21753

Abstract

As a latent heat medium, phase change material (PCM) can be applied to heat storage for solar water heaters (SWH). The method used to place PCM is to put it in a capsule. Thermal stratification is critical in generating SWH thermal efficiency. Installation of horizontal capsules in the tank has no known effect on thermal stratification. This paper aims to study the thermal stratification in active-type SWH incorporating PCM. A cylindrical capsule containing the PCM was placed inside the tank. The thermocouple was installed on both the water and PCM sides. The charging process was conducted indoors, and the water flow rate varied from 1, 2, and 3 LPM. Water temperature data for each variation was analyzed to evaluate the thermal stratification. Richardson number analysis proved that thermal stratification was formed in all water flow rates. It was found that a low water flow rate results in high thermal stratification.
Investigasi Kapasitas Energi Termal pada Solar Water Heater Berbasis Kalor Laten dengan Variasi Debit Air Nadjib, Muhammad; Caroko, Novi; Thoharudin, Thoharudin; Darmawan, Hanifan
Semesta Teknika Vol 26, No 1 (2023): MEI
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/st.v26i1.18196

Abstract

Material penyimpan kalor pada solar water heater adalah air sebagai kalor sensibel. Kekurangan air adalah densitas energinya rendah. Material lain adalah dari golongan kalor laten (phase change material, PCM) yang memiliki densitas energi tinggi. Unjuk kerja termal SWH tipe aktif dengan tangki horizontal dan memakai PCM jenis paraffin wax terhadap perubahan debit aliran air belum pernah diungkap. Tujuan penelitian ini adalah untuk mendapatkan karakteristik pengaruh perubahan debit air terhadap kapasitas penyimpanan energi termal di tangki. Penelitian menggunakan SWH dengan tangki yang di dalamnya diletakkan kapsul silinder berisi paraffin wax RT55. Termokopel dipasang di sisi air dan PCM. Eksperimen dilakukan secara indoor memakai solar simulator. Debit aliran air yang digunakan adalah 1 lpm, 2 lpm dan 3 lpm. Penelitian ini mendapatkan hasil yaitu kapasitas energi termal untuk debit aliran tersebut masing-masing adalah 10,45 MJ, 10,59 MJ dan 10,71 MJ. Semakin besar debit air maka kapasitas penyimpanan energi termal semakin tinggi.
Correlation between Physical Properties and Specific Fuel Consumption in Jatropha -Used Cooking Oil Biodiesel Mixtures Wahyudi, Wahyudi; Nadjib, Muhammad; Apriyanto, Apriyanto
Semesta Teknika Vol 26, No 2 (2023): NOVEMBER
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/st.v26i2.20163

Abstract

This study was motivated by the need to understand the influence of using waste jatropha biodiesel on the physical properties of fuel and the performance of diesel engines. The primary aim was to determine the relationship between the fuel's physical properties, spray angle, and specific fuel consumption (SFC) at various load levels. The methodology employed included measurements of density, viscosity, flash point, calorific value, spray angle, and SFC for different blends of waste jatropha biodiesel and diesel (B5, B10, B15, B20). The research results demonstrate an increase in density, kinematic viscosity, and flash point, along with a decrease in calorific value, as the biodiesel content increases. The density of the biodiesel mixture ranges from 823 kg/m³ at B5 to 836.50 kg/m³ at B20. The kinematic viscosity increases from 3.9 cSt at B5 to 5.2 cSt at B20, and the flash point rises from 112.9°C at B5 to 128.7°C for B20. Meanwhile, the calorific value decreases from 10308.2670 cal/g at B5 to 10133.8280 cal/g for B20. A strong correlation exists between density and kinematic viscosity with the spray angle, exhibiting R2 values of 0.9141 and 0.8287, respectively. The correlation between the fuel's physical properties and the specific fuel consumption (SFC) is also substantial, marked by high R2 values above 0.93. These findings provide a solid foundation for the development of more optimal biodiesel formulations.
Effect of Density and Viscosity on Injection Characteristic of Jatropha - waste Cooking Oil Biodiesel Mixture. Mariono, Mariono; Wahyudi, Wahyudi; Nadjib, Muhammad
JMPM (Jurnal Material dan Proses Manufaktur) Vol. 7 No. 1 (2023): Juni
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/jmpm.v7i1.17896

Abstract

Biodiesel has an important role in the world of transportation and its existence is taken into account. So the availability of biodiesel fuel in the future will be difficult to eliminate and must continue to be fulfilled. Therefore, it is necessary to innovate to increase the availability of biodiesel fuel. Biodiesel can be made from biological materials and includes renewable energy as a substitute for diesel oil. The production of biodiesel in this study jatropha and waste cooking oil as raw materials. This study aims to determine the effect of density and viscosity on the injection characteristics of jatropha-waste cooking oil biodiesel mixtures (1:4 and 4:1) on various B5-B40 fuels. Production of biodiesel from jatropha and waste cooking oil through degumming, esterification and transesterification processes. The results showed that the jatropha-waste cooking oil biodiesel mixed with 1:4 level B15 and 4:1 mixed with B10 level complied with SNI 7182-2015 biodiesel standards. The higher the density and viscosity values of jatropha-waste cooking oil biodiesel, the narrower the spray angle and the longer the spray penetration
Effect of Temperature on Co-Pyrolysis of Palm Kernel Shell and Plastic Waste under Natural Catalysts Thoharudin, Thoharudin; Nadjib, Muhammad; Ayatullah, Maulana Wahyu
JMPM (Jurnal Material dan Proses Manufaktur) Vol. 8 No. 2 (2024): Desember
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/jmpm.v8i2.22053

Abstract

Pyrolysis is a potential process for converting solid waste, such as biomass and plastic waste, into useful fuels and chemicals in liquid, solid, and gas forms. The pyrolysis temperature is a critical factor that influences the amount and quality of the product. Furthermore, the use of natural catalysts such as calcium oxide and natural zeolite affects the pyrolysis products. Thus, the purpose of this study is to evaluate the influence of temperature on the amount and quality of pyrolysis products, especially pyrolysis oil, using calcium oxide and natural zeolite catalysts. Pyrolysis was carried out in a stainless steel fixed-bed reactor. The temperature was kept at 400, 450, and 500 oC. The pyrolysis vapor was cooled with a water-jacket condenser, and the oil and wax were collected in an oil chamber. This study found that the pyrolysis temperatures had a substantial impact on the pyrolysis product yields by reducing the char product from 31.25% to 13.9% when the temperature rose in tandem with the fluctuations of other products (wax, liquid, and non-condensable gas). At 450 oC, the liquid product acquired its maximum density, viscosity, heating value, and acidity, which were 906.7 kg/m3, 2.2 cSt, 37.83 MJ/kg, and pH 6.2, respectively. Furthermore, increased temperature promoted the formation of aliphatic hydrocarbons..
POTENSI RISET MASA DEPAN DALAM KONTEKS RIBA Majduddin, Muhammad; Nadjib, Muhammad; Asnawi, Nur; Farid, Muhammad; Danila, Nevi
IQTISHODUNA: Jurnal Ekonomi Islam Vol. 14 No. 1 (2025): April
Publisher : LPPM, Universitas Islam Syarifuddin Lumajang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.54471/iqtishoduna.v14i1.2465

Abstract

This paper investigates the changing function of digital zakat inside Islamic social finance and emphasizes its ability to solve economic inequity and poverty in environments with a majority of Muslims. While zakat systems are fundamental to social justice, conventional management approaches struggle with inefficiency, lack of openness, and low public confidence. Digital technologies include blockchain, artificial intelligence, and integrated zakat platforms provide interesting answers with the rise of financial technology, but need appropriate alignment with maqashid al-shariah and governance systems to guarantee ethical outputs. This study maps important theme trends, methodological developments, and current research gaps in digital zakat studies utilizing a Systematic Literature Review (SLR) paired with bibliometric analysis. The results highlight the need for inclusive, data-driven, sharia-compliant digital zakat systems that strike a balance between social and ethical issues and technical developments. This paper offers both theoretical analysis and pragmatic suggestions for improving responsible zakat administration