Dr.Ir.Zuryati Djafar, MT - Academia.edu (original) (raw)

Papers by Dr.Ir.Zuryati Djafar, MT

Nucleation and Atmospheric Aerosols, 2022

International Journal of Design & Nature and Ecodynamics, Aug 30, 2023

Given Indonesia's average atmospheric humidity of 75% to 85%, this study explores the potential o... more Given Indonesia's average atmospheric humidity of 75% to 85%, this study explores the potential of atmospheric air as an alternative clean water source to mitigate water shortage. The research employs a thermoelectric cooler (TEC 1-12706), supplemented with a heatsink and fan on its hot side to enhance heat dissipation. A copper-made cooling coil serves as both a heat absorber and a condenser for atmospheric air passing through it. The cooling source for the coil (diameter=7.9mm; length=1000mm) is derived from a waterblock attached to the cooler's cold side. Experiments were conducted across three environmental conditions: laboratory, residential area, and coastal area, with the air flow rate of the heatsink cooling fan varied. Data collection spanned a humidity range of 72.27%-83.01%. Findings revealed a direct correlation between the air mass flow rate of the heatsink cooling fan and the amount of water extractable from the air. In initial testing at the Laboratory, at a mass flow rate of 0.046 kg/s it produced 4.25 ml/hour and at 0.069 kg/s it produced 4.625 ml/hour and at 0.092 kg/s it produced 5.5 ml/hour. Furthermore, from the three environmental conditions tested, more water can be extracted on the coast than in laboratories and residential areas. In coastal areas, the air mass flow rate is 0.092 kg/s, water that could be extracted is 7.75 ml/hour, while in the laboratory environment it is 5.5 ml/hour and in residential areas it is 4.75 ml/hour. These promising results encourage further research to augment water extraction by maximizing the contact surface between the air cooler and the coil surface, potentially offering a viable solution for clean water shortage.

International Journal of Design & Nature and Ecodynamics

Lecture notes in mechanical engineering, Sep 2, 2022

International Journal of Heat and Technology

Solar energy can be converted into electrical energy using photovoltaic (PV) and thermoelectric g... more Solar energy can be converted into electrical energy using photovoltaic (PV) and thermoelectric generators (TEG). In order to increase the effectiveness of energy absorption, a hot mirror or cold mirror spectrum separator is used. In this study, a simulation was carried out to see the effect of the cold mirror and hot mirror spectrum separator on the performance of the PV-TEG hybrid. Simulations are carried out using the LabVIEW program. The standard for the solar radiation spectrum used is AM1.5D. The incoming radiation is transmitted using a Fresnel lens to make it more focused and then transmitted to a cold mirror or hot mirror, where the spectral irradiance will be halved. Spectral irradiance with a wavelength of 400-690 nm will be directed to PV and a wavelength of 710-1150 nm will be directed to TEG. From the PV-TEG hybrid modeling and simulation using the LabVIEW program, the resulting power and efficiency are 240.635 W/m2 and 27% respectively for cold mirror and 228.835 W/m2...

International Journal of Design & Nature and Ecodynamics, 2022

The performance analysis of the biomass briquette stove has been carried out. The research was co... more The performance analysis of the biomass briquette stove has been carried out. The research was conducted with three variations of stove wall materials (clay, steel, and aluminum) and with several variations of shell diameter of the burning chamber (140mm, 150mm, 160mm, 170mm, and 180mm). The fuel used is coconut shell briquettes. The results showed that the maximum fire temperature of clay, steel, and aluminum stoves was obtained, respectively 798℃, 617℃, 508℃ and thermal efficiency of 73.66% for clay followed by a steel stove of 38.98% and the lowest is obtained on an aluminum-based stove, which is only 11.49%. Furthermore, the diameter of the shell optimum is 180 mm for clay, 160 for steel, and 170 for aluminum.

EPI International Journal of Engineering, 2018

The thermoelectric generator (TEG) has long been used to produce electrical energy where when a t... more The thermoelectric generator (TEG) has long been used to produce electrical energy where when a temperature difference occurs between two different semiconductor materials, this thermoelectric element will produce a voltage difference and flow an electric current. This principle is known as the 'Seebeck effect'. This research was conducted to determine the electrical energy potential of the TEG module as an alternative energy source by utilizing chimney heat from an incinerator. The test was carried out with a variation of 1, 2 and 3 m chimney height with treatment without compaction and compaction of waste. The test results show that with 12 TEG modules arranged in series electricity can produce an output voltage with a maximum temperature difference of each ΔV 3,31 Volt ; ΔT 15,0 °C (1 m), ΔV 3,92 Volt; ΔT 17,8 °C (2 m), ΔV 4,84 Volt ; ΔT 22,0 °C (3 m) while the compaction of each value ΔV 6,34 Volt ; ΔT 29,2 °C (1 m), ΔV 7,69 Volt ; ΔT 35,2 °C (2 m), ΔV 9,09 Volt ; Δ...

This device is designed by using hot air from the results of the use of rice husks and then passe... more This device is designed by using hot air from the results of the use of rice husks and then passed into the heat exchanger (heat exchanger) to convert the hot air that is still dirty into hot air which is then used for the next exploration process in the drying chamber. The study was conducted with 4 variations of environmental air blower speeds (2600 rpm, 2700 rpm, 2800 rpm, 2900 rpm) and 4 variations of hot air blower rotational speed (2600 rpm, 2700 rpm, 2800 rpm, 2900 rpm). The results showed that the hot air flow velocity with 4 variations of air flow velocity obtained the best drying room efficiency occurred at 2600 rpm at 2.26%. For a constant environment air flow with 4 variations of hot air flow velocity obtained the best space efficiency occurs at 2900 rpm of 2.55%. Abstrak. Alat ini dirancang dengan memanfaatkan udara panas dari hasil pembakaran sekam padi kemudian dialirkan ke penukar kalor (heat exchanger) untuk mengubah udara panas hasil yang masih kotor menjadi udara ...

Usage of type alcohol of etanol in gasoline fuel proves a number of machine achievements in terms... more Usage of type alcohol of etanol in gasoline fuel proves a number of machine achievements in terms of parameters, namely actual horsepower, specific fuel consumption, mean effective pressure and thermal efficiency compared to use pure premium fuel. Level of such repair gyrate 73% from maximum energy according to machine specification. In yielding etanol, fermentation process with yeast mixture then destiltaion. Etanol mixed with premium with certain ratio. In this research, variation of mixing of alcohol premium, namely: 95%+5%; 90%+10% and 85%+15% by 3 variation throttle opening: 20%, 40% and 60%. The result indicates that with usage of concentration mixing of premium + etanol, reached actual horsepower by Kijang machine 7k experiencing with maximum value equal to 17,347 kW that happened at condition of opening of throttle 60% at rotation 2100 rpm with usage of mixing 95% premium + 5% etanol. With usage of concentration mixing of premium + etanol, specific fuel consumption also exp...

EPI International Journal of Engineering, 2021

The subsidized gasoline conversion to LPG 3 kg in 2006 became the Indonesian Government’s policy ... more The subsidized gasoline conversion to LPG 3 kg in 2006 became the Indonesian Government’s policy to reduce reliance on fuel oil. The increasing LPG consumption and obstacle distribution have been the scarcity of the LPG in all regions of Indonesia. The gasoline fueled stove has overcome from the LPG scarcity. The purpose of this research was to compare the use of Gasoline types Pertalite and Pertamax with the use of LPG fuel. The research method was carried out by comparing the three types of fuel in the process of boiling 1 (one) litre of water using a gas stove, with several variations in pressure from 1.5 kPa to 2.5 kPa. The results showed that the highest fire temperature for Pertalite was 430 °C fuel, Pertamax 530 °C fuel and LPG 578 °C fuel. Fuel consumption for Pertalite 0,025 kg, Pertamax 0,027 kg and LPG 0,061 kg. The boiling time is 682 s for Pertalite, 669 s Pertamax and 503 s for LPG. The least compaction efficiency value occurs at 1.5 kPa pressure, for Pertalite 6,136 ...

EPI International Journal of Engineering, 2020

This research was conducted to determine the character of the TEG module as a source of electrica... more This research was conducted to determine the character of the TEG module as a source of electrical energy in utilizing heat in the chimney wall of an egg rack drying machine that uses rice husk as engine furnace fuel. The test is carried out by utilizing heat on 2 pieces of chimney (upper chimney and lower chimney) separated by a Heat Exchanger (HE) with a furnace blower speed of 2600 rpm and environmental blower speed of 2800 rpm with the amount of thermoelectric used as many as 44 units. The results show that the TEG module in the upper chimney obtained temperature difference (∆T), voltage difference (∆V) and power (P) respectively ∆T 38.75 ° C; ∆V 3.68 Volts; P 0.796 Watt and for the lower chimney respectively ∆T 73.25 ° C; ∆V 12.26 Volts; P 2.446 Watt.

Journal of the Japan Institute of Energy, 2020

JTT (Jurnal Teknologi Terapan), 2018

Modul termoelektrik merupakan suatu alat yang bekerja untuk menghasilkan dingin dengan memanfaatk... more Modul termoelektrik merupakan suatu alat yang bekerja untuk menghasilkan dingin dengan memanfaatkan energi listrik. Pemilihan modul ini didasarkan pada beban kalor, beda temperatur dan daya listrik yang digunakan. Termoelektrik pendingin memiliki beberapa kelebihan diantaranya tidak berisik, mudah perawatan, tidak memerlukan banyak komponen tambahan dan ramah lingkungan. Penerapan termoelektrik dengan dua tingkat atau lebih yang dikombinasikan pada mesin pendingin merupakan metode penting untuk meningkatkan kinerja termoelektrik. Pada penelitian ini akan dilakukan pengujian kinerja modul termoelektrik pendingin pada dispenser air minum dengan memanfaatkan tegangan listrik DC. Model termoelektrik yang akan diuji adalah modul ganda yang dirangkai secara seri listrik dan paralel listrik dengan meninjau temperatur air yang didinginkan, daya listrik yang digunakan termoelektrik dan kecepatan pendinginan. Hasil penelitian menunjukkan bahwa modul terbaik dari segi temperatur air, kecepatan...

JTT (Jurnal Teknologi Terapan), 2017

The most important component in the refrigerator is the refrigerant. The refrigerant absorbs heat... more The most important component in the refrigerator is the refrigerant. The refrigerant absorbs heat from one side and throw it to another side through the mechanism of evaporation and condensation. This research aims to develop a refrigeration machine using different refrigerants that can be observed with the performance of the compressor, evaporator performance and COP, and hoped this research can show the installation as a medium of learning in applying the working principle of refrigerator. The research method was experimental at setting 8 refrigeration machine with data collection for the pressure and temperature of R-12 and R-134a were measured at the compressor inlet and outlet for 300 minutes. Determining the value of the enthalpy at any point by using REFPROP program. The use of different refrigerants in a refrigeration machine indicates that the refrigerant R-134a better than R-12. It can be seen after 300 minutes for R-134a, compressor performance 29.4 kJ / kg, the performan...

Journal of Physical Science, 2018

International Journal of Biomaterials, 2019

Biochars from bamboo leaves as a potential energy resource were synthesized by annealing in the o... more Biochars from bamboo leaves as a potential energy resource were synthesized by annealing in the oxygen-free environment. Samples were characterized using proximate analysis, Fourier-transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). Heating temperatures are 250°C, 300°C, and 350°C and for each temperature, the time was varied between 30, 60, and 90 minutes. The heating time for 30 minutes results in FC 30.777% and calorific value 15 MJ/Kg at temperature 250°C and decreased to 4.004% and 6 MJ/Kg at temperature 350°C, respectively. EDS shows the time of heating is an important parameter which shows the carbon and nitrogen contents were decreasing with the increase in the heating time, and silicon and oxygen contents were increasing with increase in the heating time. XRD shows broad (002) reflections between 20° and 30°, which indicated disordered carbon with small domains of coherent and parallel stacking o...

Journal of Physics: Conference Series, 2019

The amount of photon energy becomes a key parameter that determines the release of electron bonds... more The amount of photon energy becomes a key parameter that determines the release of electron bonds which is often called a band-gap in photovoltaic cells (PV) to generate electricity. This paper presents the results of measurements of photon energy from radiation sources of artificial light Halogen, Incandescent and Xenon which aims to adjust the bad gap type of solar cell material. Simulations of measuring 50 watts of bulb radiation were carried out repeatedly with the Spectrometer sensor and the application software Spectragryph 1.2.8 on each electron Volt the bulb light. The incoming radiation form the bulb is concentrated with a Polymethylmetacrylate (PMMA) Fresnel lens with an optimal light transmission capability of 92%. The results of this light transmission will be divided after illuminating at the Cold mirror (CM) spectrum splitterr, partly reflected in the PV module and partially transmitted to the thermoelectric generator (TEG) in the PV-TEG hybrid. The measurement of phot...