Article Per Year (5 Year)
p-Index From 2021 - 2026
2.024
P-Index
This Author published in this journals
All Journal Jurnal Penelitian dan Pengembangan Pendidikan Rekayasa Mesin Journal of Engineering and Management in Industrial System ROTOR: JURNAL ILMIAH TEKNIK MESIN Journal of Energy, Mechanical, Material and Manufacturing Engineering Prosiding Seminar Nasional Teknik Mesin International Journal of Mechanical Engineering Technologies and Applications (MECHTA) Asean Journal of Science and Engineering (AJSE) Prosiding SNPBS (Seminar Nasional Pendidikan Biologi dan Saintek) Prosiding SEMNAS INOTEK (Seminar Nasional Inovasi Teknologi) Jurnal Polimesin
Widya Wijayanti
Department of Conservative Dentistry, Faculty of Dentistry, Universitas Indonesia, Jakarta 10430
Aerospace Engineering Agriculture, Biological Sciences & Forestry Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Education Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mathematics Mechanical Engineering Transportation

Published : 34 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 34 Documents
Search

 1   2   3   4 
Pengaruh Temperatur Terhadap Entalpi dan Kinetic Rate Gas Pirolisis Kayu Mahoni Suwandono, Purbo; Wijayanti, Widya; Hamidi, Nurkholis
Jurnal Rekayasa Mesin Vol 6, No 1 (2015)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (563.683 KB) | DOI: 10.21776/ub.jrm.2015.006.01.9

Abstract

This study was conducted to determine the effect of temperature on gas enthalpy and kinetic rate of mahogany wood powder pyrolysis results. Research process carried out experimentally with the temperature 673 K, 773 K, 873K, 973 K and 1073 K. Pyrolysis process is carried out for 2 hours with a particle size of sawdust from 0.5 to 1 mm. The results showed that the enthalpy value increase as the temperature increase. Highest enthalpy value achieved at 1073 K, with enthalpy value is 35015.97J.Kinetic rate for temperature 873 K, 973 K and 1073 K is 𝑘 = 1,484𝑒 −2759/𝑇 , kinetic rate for temperature 673 K and 773 K is 𝑘 = 16,5306𝑒 −5368/𝑇 and 𝑘 = 3,0373𝑒 −2980/𝑇 respectively. As the temperature increase, activation energy (Ea) to decompose biomass into gases is decrease.
Pengaruh Prosentase Etanol terhadap Torsi dan Emisi Motor Indirect Injection dengan Memodifikasi Engine Control Module Rahmad, Hadi; Sasongko, Mega Nur; Wijayanti, Widya
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 | Full PDF (531.641 KB) | DOI: 10.21776/ub.jrm.2016.007.02.2

Abstract

This research present the torque and exhaust emission level from four stroke indirect injection fuel system engine. An engine fueled by ethanol gasoline blend. The original Engine Controle Module injected lean mixture into Combustion Chamber. Lean Mixture decreased Torque drastically. Therefore, the Engine Controle Module was modified to produce stoichiometric mixture. Injector was controlled by digital pulse of Fuel Controller. Ethanol was added into gasoline 0% - 100% at 1500 rpm-5000 rpm. The result demonstrate that increasing ethanol concentration into gasoline fuel system, decreasing Torque, and CO, HC, CO2 emission. By increasing ethanol concentration also increase CO2 emission to 34.6%.
Pengaruh Campuran Sampah Plastik dengan Katalis Alam terhadap Hasil Produk Pyrolisis Nuryosuwito, Nuryosuwito; Soeparman, Sudjito; Wijayanti, Widya; Sasongko, Mega Nur
Rekayasa Mesin Vol 9, No 2 (2018)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (333.192 KB) | DOI: 10.21776/ub.jrm.2018.009.02.3

Abstract

Currently, various methods have been developed to overcome the problems caused by garbage. Pyrolysis is one methode of waste processing which is considered to be prospective enough to be developed. It?s because some advantages such as high conversion ratio and high energy content and potency as an alternative fuel in the future. Therefore, in this paper characteristics of pyrolysis will be studied. The waste materials used are catalyst and plastic waste. The resultant products of the pyrolysis process analyzed by Gas Chromatography / Mass Spectroscopy (GC / MS), while the thermal decomposition analysis was performed using Thermo Gravimetric Analysis (TGA). The results of pyrolysis process in isothermal conditions of a single component and a mixture of plastic waste and natural catalyst show that the final temperature of pyrolysis and the rate of heating affects to the distribution of pyrolysis products for all samples. As pyrolytic temperatures increase, liquid and gas products increase, while solid products tend to decrease. In the temperature range of 300°C, 400°C, 500°C, 600oC pyrolysis temperature with a heating rate of 100°C / min is the ideal temperature for obtaining the pyrolysis product of the liquid fraction and and the maximum gas fraction for all waste types studied.
Identifikasi Komposisi Kimia Tar Kayu Mahoni untuk Biofuel pada Berbagai Temperatur Pirolisis Wijayanti, Widya
Jurnal Rekayasa Mesin Vol 9, No 3 (2018)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (540.097 KB) | DOI: 10.21776/ub.jrm.2018.009.03.5

Abstract

This study indentified the tar yield of pyrolysis of mahogany wood. The produced tar would be analyzed using GC-MS (Gas Chromatograph-Mass Spectrometry) to understand their chemical properties affected by temperature pyrolysis. It would be identified if the elements are flammable matters or not. It is due to the fact that the yields of pyrolysis desire the flammable matters as much as possible as a biofuel. The experiment was conducted at a fixed bed reactor. The needle particle of mahogany wood was used as the pyrolysis feedstock having weight of 200 gram, sizing of mesh 20 hm, and containing 2% moisture content. The variations of pyrolysis temperature influencing the mahogany wood decompositions are 250°C, 350°C, 450°C, 500°C , 600°C, 700°C and 800°C. The pyrolysis was carried out during 3 hours almost without Oxygen. The result of tar yields show that a getting higher of the pyrolysis temperature caused the volume and mass of tar formed by condensation in cold trap would increase up to 500°C and then decrease. The increasing of tar yields would also increase some acetic acid compounds and reach a peak at 350°C in which the acetic acid compound is a flammable substance. From the GC-MS results, it was also presented that at any pyrolysis temperatures, the amount of the flammable tar compounds were higher than the unflammable one. It can be interpreted that the tar yield is very potential as liquid fuel (bio-oil) because the main elements of tar is acetic acid having flash point (flash point) equal to 39°C.
Identifikasi Efek Heating Rate terhadap Laju Kinetika Reaksi Pirolisis Kayu Mahoni dengan Thermal Analysis dan Termogravimetry Wijayanti, Widya
Rekayasa Mesin Vol 10, No 1 (2019)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jrm.2019.010.01.9

Abstract

The study was conducted to investigate the biomass pyrolysis using mahogany wood as the feedstock. Chemically, mahogany wood contained complex biomass compounds, consisting of cellulose, hemicellulose, and lignin. Each biomass compound had its degradation at a certain temperature. Therefore, their compounds will be pyrolyzed at some different temperatures to understand the certain one. In the experiment, the biomass was hydrolyzed based on the temperature differences from room temperature to a temperature around 1000ºC (1273 K). We identified pyrolysis kinetic rate and measured some appropriate pyrolysis temperatures to accomplish the pyrolysis process. Afterward, the investigation of its thermal degradation used Thermal Analysis and Thermogravimetric (TGA) analysis. It would be obtained the estimation of energy needed to obtain a mathematical equation determined by the dependencies of the pyrolysis temperature by using LINSEIS STA Platinum Series. The mathematical equation was gained by using the temperature difference profiles (differential thermal analysis-DTA) and the biomass weight loss (difference thermogravimetry-DTG) by means of TGA. It was measured under the inert condition without Oxygen at the heating rate of 400°C/h and 800°C/h. By using order-1 differential equations, the activation energy, and pre-exponential factors also were determined in the mathematical equation of the kinetic reaction rate equation as k1 = 7.9033  for a heating rate of 400°C/h and k2 = 9.7745  for heating rate 800°C/h.
Pengaruh Temperatur terhadap Laju Reaksi Tar Hasil Pirolisis Serbuk Kayu Mahoni pada Rotary Kiln Nugroho, Andi; Wijayanti, Widya; Sasongko, Mega Nur
Rekayasa Mesin Vol 10, No 2 (2019)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jrm.2019.010.02.2

Abstract

Pyrolysis is a thermochemical process chemical decomposition of organic substances through the heating process without oxygen. It produced char, tar, and gas. Rotary kiln Pyrolysis is horizontal stove with biomass that being moved in certain rotary along the stove. Biomass particle movement in rotary kiln concentrated at the wall of the kiln in the passive layer. This layer will reach the surface where the layer will move to the bottom of the active layer. This research is an experimental study done with temperature variation 2500 C, 350OC, 450OC,500OC and 600oC, the nitrogen flow rate 3 ml/min and the pyrolysis time is 180 minutes. The equipment that used is built and developed for better result of observation using rotary klin. The rotary kiln will rotate uses an electric motor with velocity 3 rpm. Then a kinetic rate enumeration process is done. The experiment result shows that the temperature is so influential to the tar volume, the higher the temperature, the more tar volume we got. The highest number is at temperature variation 500o C with heating rate 1073 km/hour. The number of tar kinetic rate that produced from enumeration shows that the higher the temperature so the kinetic rate resulted is greater and the analysis result shows that tar volume from the enumeration approximates the actual number of tar volume.
EXPERIMENTAL INVESTIGATION ON COMBUSTION CHARACTERISTICS OF REFINE CORN OIL WITH ARECA CATECHU EXTRACT AS ADDITIVE Wardoyo, Wardoyo; Widodo, Agung S.; Wijayanti, Widya; Wardana, I. N. G.
Journal of Energy, Mechanical, Material, and Manufacturing Engineering Vol 5, No 1 (2020)
Publisher : University of Muhammadiyah Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (723.925 KB) | DOI: 10.22219/jemmme.v5i1.11990

Abstract

The need for vegetable oils as alternative energy reserves increases with the depletion of fossil energy sources. Vegetable oil is the strongest candidate to replace the fossil energy. However, the use of vegetable oil directly as fuel is limited by high viscosity. Viscosity like this results in non-ideal atomization, challenging to evaporate, and cannot burn completely. Among the methods that have been studied by previous researchers and which have proven to be effective, cheaper, and can reduce the viscosity of vegetable oils better is the mixing method. In this study, corn oil was mixed with areca extract as an additive. Areca extract contains polyphenols which are polar types of epicatechin. Epicatechin has three aromatic rings and several hydroxyl groups. Delocalisation of electrons in aromatic rings can produce London forces on vegetable oil molecules, thereby increasing the reactivity of burning vegetable oil droplets. The burning characteristics of corn vegetable oil affected by areca extract have been studied experimentally at room temperature and atmospheric pressure. The results showed that the rate and temperature of combustion increased, as well as the presence of micro explosions. The London force that appears causes the bonds in the triglyceride molecules to weaken so that the combustion becomes reactive, the rate of heat transfer in the droplets gets better, facilitates the appearance of micro explosions and increases the combustion temperature. Vegetable oil from corn has been studied experimentally at atmospheric pressure and room temperature. The results show an increase in the rate of combustion, an increase in combustion temperature, and the presence of micro explosions. London force that appears causes the bonds in the triglyceride molecules to weaken so that combustion becomes more reactive, the rate of heat transfer in the droplet gets better, facilitates the appearance of micro explosions and raises the combustion temperature.
Pengaruh Temperatur Reformer Bed terhadap Performa Propane Steam Reformer Menggunakan Comsol Multiphysics 5.3ª Kusumastuti, Rizky; Tseng, Chung-Jen; Wijayanti, Widya; Sasmoko, Sasmoko
Jurnal Rekayasa Mesin Vol 11, No 2 (2020)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jrm.2020.011.02.8

Abstract

Steam reforming is a method for producing hydrogen gas as a solution for renewable energy generation. One source of hydrogen in a steam reformer is propane gas. The advantage of propane gas is the ease of transportation and storage. The production of hydrogen gas in a steam reformer is certainly influenced by supporting factors such as the temperature of the reformer. In this study, propane steam reforming was simulated in 3D with COMSOL Multiphysics 5.3ª software with bed reformer temperatures varying from 600, 650, 700, 700, 750, 800 and 850 oC with steam to carbon (S/C) ratio 3. The results show that increasing the temperature causes the density of the reformer to decrease, which in turn results in increased gas velocity. In addition, an increase in temperature in the bed reformer increases propane conversion to 87.8% and produces about 40% hydrogen at 850 oC.
Pengembangan Media PowerPoint IPA Untuk Siswa Kelas IV SD Negeri Samirono Wijayanti, Widya; Christian Relmasira, Stefanus
Jurnal Penelitian dan Pengembangan Pendidikan Vol 3, No 2 (2019): Juli
Publisher : LPPM Undiksha

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23887/jppp.v3i2.17381

Abstract

Penelitian ini merupakan penelitian Research and Development yang menghasilkan media  berupa media pembelajaran berbasis teknologi terutama media PowerPoint IPA untuk siswa kelas IV.  Penelitian ini bertujuan untuk kebutuhan sekolah, meningkatkan ketertarikan dan menghasilkan media PowerPoint untuk peserta didik yang layak. Pengembangan media PowerPoint dilakukan dengan 3 langkah pokok yang harus dilakukan yaitu yang Pertama, studi pendahuluan untuk mengetahui kebutuhan Sekolah Dasar dan pentingnya media. Kedua, penyusunan draft produk memulai tahap pembuatan desain PowerPoint, validasi materi, validasi media. Ketiga,  uji coba produk untuk siswa kelas IV. Hasil penelitian ini berupa media pembelajaran berbasis Teknologi terutama PowerPoint yang berisi materi pendidikan IPA Subtema 2 yang telah divalidasi oleh ahli media, ahli materi, dan dinyatakan layak. Media PowerPoint telah diuji cobakan kepada siswa Sekolah Dasar dan siswa mampu memahami materi IPA tentang Selalu Menghemat Energi. Pada tujuan Pengembangan Media PowerPoint IPA menggunakan model AADIE untuk mengetahuo seberapa tinggi validasi produk model oleh ahli. Valdasi materi pembelajaran oleh ahli materi diperoleh sebesar 75,5% dengan kategori tinggi dan validasi media pembelajaran oleh ahli media diperoleh sebesar 46,25% dengan kategori tinggi. Selain mengetahui seberapa tinggi validasi ahli juga untuk melihat apakah media PowerPoint dapat menarik siswa dalam pembelajaran menggunakan teknologi.
Efek Intermolecular Forces: Perubahan Physical Properties pada Campuran Premium dan Bio-Additive Orange Peel Musyaroh, Musyaroh; Wijayanti, Widya; Sasongko, Mega Nur; Rizaldy, Ahmad Difal
Jurnal Rekayasa Mesin Vol 12, No 1 (2021)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jrm.2021.012.01.15

Abstract

The addition of bio-additive in gasoline was needed in order to improve the anti-knock quality. The bio-additive used was orange peel in the form of essential oil. Nevertheless, it make any changes of fuel properties affecting standard compliances: physical properties, engine performances and exhaust gas emissions due to some main compound effects of orange oil; limonene up to 90%. The recent study aimed to analyze the blends of bio-additives and premium gasoline  experimentally related to improve the fuel properties theoretically. By verifying the blends, they were tested at blending concentration ratio from 1% to 75%. For each blend, the physical properties; kinematic viscosity, density, and calorific value were measured using ASTM D 445, ASTM D 92, and ASTM D 250.  The results show that the limonene gave many impacts on the change of properties fuel. Limonene is a non-polar compound with high intramolecular force intensity. It causes a spontaneous dipole and gave propagation effect on premium gasoline molecular compound. The effect influences dynamic molecular distribution by increasing the attractive force between opposite pole of premium gasoline and bio-additives blend. The decrease of intermolecular movement intensity will decrease the viscosity of the mixture. In contrary, the kinematic viscosity of the mixture will increase with increasing bio-additive concentration. In other pysical properties, the premium gasoline-bio-additive blends have low density at 1%, 5%, 10% and 25% addition concentration but it has high heating value of fuel blends.
Co-Authors A.A. Ketut Agung Cahyawan W Ahmad Yani Akbar, Dzulfikar Johan Akhlis Rizza, Muhammad AM Mufarrih Amir, Ahmad Ihwan Andi Nugroho, Andi Christia Meidiana Christian Relmasira, Stefanus Denny Widhiyanuriyawan Dody Candra Kumara, Dody Candra Dwi Irawan Eko Siswanto Farid Majedi, Farid Hamidi, Nurcholis I Nyoman Gede Wardana I.N.G. Wardana Ikhwanul Qiram ING Wardana Kusumastuti, Rizky Kusumo, Herma Nugroho rono adi Lilis Yuliati Mega Nur Sasongko Musyaroh, Musyaroh Nova Risdiyanto Ismail Nurkholis Hamidi Nuryosuwito, Nuryosuwito Nuzullis Lailatul Kamaliyah Pambudi, Wisnu Setyo Catur Pratikto Pratikto Purbo Suwandono Rahmad, Hadi Razi, Misru Razi, Misru Rizaldy, Ahmad Difal Rudy Soenoko S., Sudjito Sangkilang, Elvinda Sasmoko, Sasmoko Setiadhi, David Slamet Wahyudi Sofana, Ilyas Stefanus Christian Relmasira Sudjito Soeparman Sugiono Sugiono Tseng, Chung-Jen Wardana, I. N. G. Wardoyo Wardoyo Wibowo, Moh. Muhyidin Agus Widodo, Agung S. Wijayanto, Vera Dwi