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"Gas Tungsten Arc Welding (GTAW) atau dapat disebut juga tungsten inert gas (TIG) merupakan proses pengelasan yang memberikan kualitas hasil lasan yang baik dengan biaya yang relatif lebih rendah. Namun, kemampuan proses pengelasan ini terbatas pada pada kapasitas penetrasi yang berujung pada produktivitas yang rendah. Dengan itu, pengembangan harus dilakukan untuk meningkatkan kemampuan penetrasi. Untuk pengembangan tersebut, metode penggunaan fluks pengaktif diperkenalkan pertama kali oleh Paton Welding Institute untuk pengelasan TIG yang digunakan pada material sebelum pengelasan. Dapat diketahui bahwa adanya peningkatan penetrasi dari pengamatan geometri hasil lasan dan sejak itu penggunaan fluks pengaktif yang disebut A-TIG menjadi banyak digunakan dan memberikan pengaruh besar.Penelitian kali ini meninjau proses pengelasan A-TIG yang mencakup beberapa kegiatan eksperimental yang sudah diteliti sebelumnya pada material baja tahan karat SUS 304. Dalam pengelasan A-TIG, parameter-parameter seperti arus, tegangan, kecepatan pengelasan, gas pelindung, dan jenis fluks mempengaruhi kualitas lasan. Selain itu, beberapa pengujian telah dilakukan pada struktur makro dan sifat mekanik untuk memiliki pemahaman yang lebih baik tentang pengelasan A-TIG.......Gas Tungsten Arc Welding (GTAW) or can also known as tungsten inert gas (TIG) is one of the welding processes that provide good weld quality with relatively lower costs. However, this welding process is limited to penetration capacity which results in low productivity. With that regard, a development must be done to improve the ability of penetration. In this case, the method of using activated flux was first introduced by Paton Welding Institute for TIG welding by using it on the material before welding. It was obsereved that there was an increase in penetration on the weld geometry and by that the use of activated flux, called A-TIG, becomes more widely used and has a major influence.In this study, the A-TIG welding process is discussed from several experimental activities that have been previously carried out on stainless steel SUS 304. In A-TIG welding, parameters process such as current, voltage, welding speed, gas shield, and type of flux affect weld quality. In addition, several testings was made on the macrostructure and mechanical properties to have a better understanding on A-TIG welding."

"ABSTRAKDeposit logam las SMAW 308L dengan variasi ferrit, nitrogen dan fluk basicity dievaluasi untuk meneliti pengaruhnya terhadap kekuatan mekanik dan perilaku korosi. Sifat mekanik diteliti melalui kekuatan tarik pada suhu kamar, charpy impak V-notch dan lateral expansion (LA) di suhu kriogenik -196oC. Polarisasi siklik potensiodinamik dilakukan pada lingkungan NaCl 3.5%w.t untuk mengamati potensial pitting dan hysteresis loop.Peningkatan ferrit dari 2-10FN, secara umum meningkatkan kekuatan logam lasan sebesar 0.5-4.9%. Pengurangan ferrit dari 4FN menjadi 2FN, meningkatkan secara signifikan charpy impak sebesar 21% dan LA sebesar 69%. Lasan dengan kandungan nitrogen yang lebih rendah memiliki charpy impak 10% lebih tinggi dan LA 37% lebih tinggi. Fluk tipe basa memiliki charpy impak 16% lebih besar dan LA 51% lebih besar.Positif hysteresis loop menunjukkan bahwa logam 308L rawan terhadap korosi pitting pada lingkungan NaCl 3,5%wt. Keberadaan ferrit mengurangi ketahanan terhadap korosi sumuran yang ditandai oleh penurunan nilai Epit. Nitrogen yang lebih rendah mengakibatkan Epit menjadi lebih aktif sementara itu Fluk tipe basa memiliki Epit yang lebih noble.Ketangguhan kriogenik dan ketahanan korosi pada logam las 308L dikontrol oleh kandungan ferrit yang rendah, kandungan nitrogen yang rendah dan fluk yang lebih basa. Sementara itu kekuatan mekanik dikontrol oleh kandungan ferrit yang tinggi

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ABSTRACTSMA (Shielded Metal Arc) welds metal 308L with variation in ferrite, nitrogen and flux basicity were evaluated in order to study its influence to mechanical and corrosion behavior. Mechanical behaviors were investigated by using tensile strength at room temperature, charpy impact V-notch and lateral expansion(LA) at cryogenic temperature -196oC. Cyclic polarization potensiodynamic was performed at 3.5% NaCl to observe pitting potential and hysteresis loop.Increment ferrite from 2-10 FN, in general increased 0.5- 4.9% welds strength. Reduction from 4FN to 2 FN had significantly increased charpy impact and LA to 21% and 69% respectively. Weld with lower nitrogen content had 10% higher charpy impact and 37% higher LA. Basic flux significantly increased charpy impact to 16% and LA to 51%.Positive hysteresis loop showed that 308L welds were prone to pitting corrosion at 3.5%w.t chloride solution. Present of ferrite reduced pitting corrosion resistance which indicated by Epit reduction. Lower nitrogen showed more active Epit. Weld with higher flux basicity resulted noble Epit.Cryogenic toughness and corrosion resistance at SMA 308L weld metal are controlled by low ferrite content, low nitrogen content and more basic flux. Meanwhile weld metal strength are controlled by high ferrite content."

"Kebakaran di tangki timbun yang berisi bahan bakar berbasis hidrokarbon jarang terjadi, namun begitu terjadi, kerugian yang diderita cukup besar baik secara ekonomi, manusia dan lingkungan. Ini disebabkan oleh kebakaran api di satu tangki dapat menyebar ke tangki lain yang berdekatan karena efek radiasi panas. Pendinginan permukaan menggunakan sistem berbasis air merupakan cara yang efektif dan sederhana. Penelitian ini merupakan studi perbandingan atas metode-metode pendinginan permukaan tangki, yaitu yang terdiri atas metode semprotan air, metode kabut air, dan metode aliran air pada permukaan tangki. Pengujian tersebut akan menunjukkan pengaruh dari masing-masing metode dalam mengurangi pengaruh radiasi panas yang diterima oleh tangki yang berdekatan. Hasil yang diperoleh adalah untuk melihat sistem mana yang paling efektif menyerap radiasi panas dan efisien dalam penggunaan air.......Fires in storage tanks containing hydrocarbon-based fuels are rare, but once they occur, the losses suffered are quite large. This is because a fire in one tank can spread to other adjacent tanks due to the radiant heat flux effect. A common idea that surface cooling by using a water-based system is an effective and simple way, whatever the material to be cooled. This research is conducted to provide a study of reducing heat flux of tank surface adjacent a burning tank by using three different methods which are by using water film, water mist and water spray as cooling system on the surface of adjacent fuel tank. The three methods will be compared each other and shall show the effect to cool the surface, whether each method can effectively reduce the radiant heat flux received by the adjacent tanks. The study shows that water spray method has a most effective method to reduce radiant heat flux on the surface of an adjacent tank."

"Karakteristik refrigerant natural (Propane) perlu dikaji lebih dalam saat ini, karena penggunaan refrigerant konvensional (sintetis) sudah mulai dibatasi karena tingginya Ozone Depletion Potential (ODP) dan Global warming potential yang berbahaya untuk keberlangsungan ozon dan menaikkan peluang naiknya suhu bumi. Karakteristik yang ditinjau dalam penelitian ini adalah penurunan tekanan dari masing-masing refrigerant yang dilakukan dengan memvariasikan fluks massa dan fluks kalor. Variasi fluks kalor untuk kedua refrigerant pada penelitian ini adalah 0.20 KW/m2 - 0.69 KW/m2. Sementara untuk fluks massa dari kedua refrigerant diatur supaya mendekati nilai yang sama. Hasil yang didapat adalah penurunan tekanan dipengaruhi oleh fluks kalor danfluks massa serta R-290 mempunyai penurunan tekanan lebih rendah dibanding R-22.......The characteristics of natural refrigerants (Propane) need to be studied more deeply at this time, because the use of conventional (synthetic) refrigerants is starting to be limited due to the high Ozone Depletion Potential (ODP) and Global warming potential which are dangerous for the sustainability of ozone and increase the chance of rising earth temperatures. The characteristic reviewed in this research is the pressure reduction of each refrigerant which is carried out by varying the mass flux and Heat flux. The variation in Heat flux for the two refrigerants in this study was 0.20 KW/m2 - 0.69 KW/m2. Meanwhile, the mass flux of the two refrigerants is adjusted to approach the same value. The results obtained are that the pressure drop is influenced by Heat flux and mass flux and R-290 has a lower pressure drop than R-22. This predicted result is in accordance with research conducted by A.S Pamitran et al (2010) in testing pressure drops for 5 types of refrigerants."

"[ABSTRAKMotor BLDC menjadi motor yang sangat banyak digunakan sekarang karena kelebihannya dibandingkan dengan motor lainnya dalam hal efisiensi, kecepatan dan torsi yang lebih baik, serta umur yang cenderung lebih panjang. Banyak dilakukan penelitian untuk meningkatkan kinerja dari motor BLDC. Penelitian ini bertujuan untuk mencari rancangan motor yang paling optimal, dengan membuat rancangan yang divariasikan pada bagian stator. Penelitian ini dilakukan dengan simulasi motor tanpa beban dan dengan beban.Pada penelitian ini dibuat empat variasi bukaan alur yang dilakukan pada simulasi tanpa beban dan berbeban. Variasi yang dilakukan adalah membuat lengkungan pada alur dan memvariasikan ukuran bukaan alur pada stator. Pada penelitian ini didapatkan nilai-nilai flux linkage, Back EMF kemudian diolah untuk mendapat Ke pada keadaan tanpa beban dan torsi ripple pada keadaan berbeban untuk dibandingkan agar dapat mengetahui rancangan mana yang memiliki performa terbaik. Pada penelitian ini ditemukan bahwa dengan rancangan ukuran yang tepat pada bagian bukaan alur di stator dapat mengurangi daerah saturasi, sehingga pada daerah yang terdapat saturasi dapat diminimalisir panas pada bagian daerah stator motor tersebut dan dapat memperkecil nilai torsi ripple hingga persentase sebesar 6.78% dengan rata-rata torsi ripple sebesar 0.583596818 Nm.ABSTRACTBLDC motors which becoming very widely used now because of its advantages compared to other motor in terms of efficiency, speed and better torque and life tend to be longer. Many research to improve the performance of the BLDC motor. This study aims to find the most optimal motor design, to create designs that varied in the stator. This research was conducted by simulating the motor no load and load.In this study is made of four variations of slot opening performed on the no load and load simulation. Variations to do is make the fillets in the slot opening and varying the size of the slot opening in the stator. In this study obtained values of flux linkage, Back EMF and then processed to obtain Ke in the load simulationand torque ripple at the load simulation of each design are compared to determine which designs that have the best performance.This research found that the design of the right size in the slot opening in the stator can reduce the saturation region, so that in the area there is saturation can be minimized heat in the area of the motor stator and can minimize torque ripple value up to a percentage of 6.78% with an average of 0.583596818 Nm of torque ripple.;BLDC motors which becoming very widely used now because of its advantages compared to other motor in terms of efficiency, speed and better torque and life tend to be longer. Many research to improve the performance of the BLDC motor. This study aims to find the most optimal motor design, to create designs that varied in the stator. This research was conducted by simulating the motor no load and load.In this study is made of four variations of slot opening performed on the no load and load simulation. Variations to do is make the fillets in the slot opening and varying the size of the slot opening in the stator. In this study obtained values of flux linkage, Back EMF and then processed to obtain Ke in the load simulationand torque ripple at the load simulation of each design are compared to determine which designs that have the best performance.This research found that the design of the right size in the slot opening in the stator can reduce the saturation region, so that in the area there is saturation can be minimized heat in the area of the motor stator and can minimize torque ripple value up to a percentage of 6.78% with an average of 0.583596818 Nm of torque ripple.;BLDC motors which becoming very widely used now because of its advantages compared to other motor in terms of efficiency, speed and better torque and life tend to be longer. Many research to improve the performance of the BLDC motor. This study aims to find the most optimal motor design, to create designs that varied in the stator. This research was conducted by simulating the motor no load and load.In this study is made of four variations of slot opening performed on the no load and load simulation. Variations to do is make the fillets in the slot opening and varying the size of the slot opening in the stator. In this study obtained values of flux linkage, Back EMF and then processed to obtain Ke in the load simulationand torque ripple at the load simulation of each design are compared to determine which designs that have the best performance.This research found that the design of the right size in the slot opening in the stator can reduce the saturation region, so that in the area there is saturation can be minimized heat in the area of the motor stator and can minimize torque ripple value up to a percentage of 6.78% with an average of 0.583596818 Nm of torque ripple., BLDC motors which becoming very widely used now because of its advantages compared to other motor in terms of efficiency, speed and better torque and life tend to be longer. Many research to improve the performance of the BLDC motor. This study aims to find the most optimal motor design, to create designs that varied in the stator. This research was conducted by simulating the motor no load and load.In this study is made of four variations of slot opening performed on the no load and load simulation. Variations to do is make the fillets in the slot opening and varying the size of the slot opening in the stator. In this study obtained values of flux linkage, Back EMF and then processed to obtain Ke in the load simulationand torque ripple at the load simulation of each design are compared to determine which designs that have the best performance.This research found that the design of the right size in the slot opening in the stator can reduce the saturation region, so that in the area there is saturation can be minimized heat in the area of the motor stator and can minimize torque ripple value up to a percentage of 6.78% with an average of 0.583596818 Nm of torque ripple.]"

"[ABSTRAKSejak teknologi magnet permanen ini mulai banyak dikembangkan, motor BLDC telah digunakan untuk berbagai aplikasi . Motor BLDC dengan kapasitas daya yang besar banyak digunakan untuk penggerak utama mobil listrik, sepeda listrik, mesin penggerak pada industri-industri. Bentuk atau geometri serta dimensi dari bagian-bagian motor adalah salah satu topik yang umum dibahas dan diteliti dalam riset pengembangan perancangan motor BLDC. Motor BLDC menggunakan magnet permanen pada rotornya sebagai sumber medan magnet. Aliran fluks mempengaruhi torque ripple. Salah satu yang paling mempengaruhi aliran fluks magnet pada motor BLDC adalah bentuk dari stator. Stator sendiri dapat divariasikan bentuknya yang dapat mengatur aliran fluks dari magnet. Pada penelitian ini divariasikan perancangan bentuk stator untuk perancangan rotor yang sama. Variasi yang dilakukan adalah variasi ukuran lebar gigi dan yoke. Pada penelitian ini ditemukan bentuk ukuran yang optimal dari enam variasi yang digunakan adalah bentuk perancangan payung lengkungan stator yang memiliki lebar gigi 10 mm, ukuran lebar yoke 125 mm dan ukuran lebar alur bukaan sebesar 2.4 mm. Pada penelitian ini ditemukan bahwa dengan perancangan ukuran yang tepat dan dengan memberikan lengkungan pada bagian kaki stator dapat mengurangi daerah saturasi, sehingga pada daerah yang terdapat saturasi dapat diminimalisir panas pada bagian daerah stator motor tersebut dan dapat memperkecil nilai torsi ripple hingga persentase sebesar 2.31% dengan rata-rata torsi ripple sebesar 0.579770359 Nm.ABSTRACTSince the permanent magnet technology is starting much developed, BLDC motors have been used for various applications. BLDC motors with high power capacity widely used for main propulsion electric vehicles, electric bike, the engine of the industries. Shape or geometry and dimensions from parts of motors is one of the general topics discussed and studied in the research design development BLDC motor. BLDC motors use permanent magnets in the rotor as the source of the magnetic field. Flux flow affects the torque ripple. One of the most affecting the flow of magnetic flux in BLDC motors is the shape of the stator. Stator can be varied forms which can regulate the flow from magnetic flux. In this research designs varied forms of stator for the same rotor design. A variation performed are wide variations tooth thickness and yoke. This research found optimal size form of the six variations used is a forms of umbrella design opening stator which has a tooth width of 10 mm, 125 mm widths yoke and the size of the slot opening width of 2.4 mm. In this research it was found that the design of the right size and by providing fillet on the legs stator can reduce the saturation region, so that the area contained saturation can be minimized heat in the area of the motor stator and can reduce torque ripple to a percentage value of 2.31% with an average of 0.579770359 Nm of torque ripple., Since the permanent magnet technology is starting much developed, BLDC motors have been used for various applications. BLDC motors with high power capacity widely used for main propulsion electric vehicles, electric bike, the engine of the industries. Shape or geometry and dimensions from parts of motors is one of the general topics discussed and studied in the research design development BLDC motor. BLDC motors use permanent magnets in the rotor as the source of the magnetic field. Flux flow affects the torque ripple. One of the most affecting the flow of magnetic flux in BLDC motors is the shape of the stator. Stator can be varied forms which can regulate the flow from magnetic flux. In this research designs varied forms of stator for the same rotor design. A variation performed are wide variations tooth thickness and yoke. This research found optimal size form of the six variations used is a forms of umbrella design opening stator which has a tooth width of 10 mm, 125 mm widths yoke and the size of the slot opening width of 2.4 mm. In this research it was found that the design of the right size and by providing fillet on the legs stator can reduce the saturation region, so that the area contained saturation can be minimized heat in the area of the motor stator and can reduce torque ripple to a percentage value of 2.31% with an average of 0.579770359 Nm of torque ripple.]"

"Perpindahan kalor selalu terjadi dalam kehidupan sehari-hari manusia dan dapat dirasakan manfaatnya maupun kerugiannya. Perpindahan kalor sendiri terbagi menjadi tiga menurut media perantaranya, yaitu konduksi, konveksi, dan radiasi. Salah satu contoh kasus dimana terdapat ketiga proses dari pepindahan panas adalah saat terjadi kebakaran dalam suatu ruangan. Saat kebakaran, panas dari api akan berpindah ke lingkungan sekitar dan mengenai benda-benda di sekitarnya dengan radiasi, konduksi, dan konveksi. Kalor yang berpindah melalui radiasi tentunya tidak memerlukan media penghantar karena kalor tersebut berpindah dalam bentuk gelombang elektromagnetik dan dapat berpindah sampai jarak yang jauh. Jarak, faktor pandang, dan penempatan dari suatu benda akan mempengaruhi besarnya radiasi yang akan diterima dari kalor api. Oleh karena itu, untuk menguji pengaruh dari jarak, faktor pandang dan penempatan benda terhadap radiasi dirancang alat dengan sensor fluks kalor multi-axis. Alat dengan sensor fluks kalor multi-axis atau dengan nama Radiometer Multi-Axis akan dirancang yang kemudian akan diuji untuk mengetahui hasil dari rancangan. Alat disebut Multi-Axis karena meja kerja dari alat dapat diputar 90o. Pengujian dari alat akan meliputi temperatur pemanas, jarak sensor terhadap pemanas, offset sensor terhadap pemanas, sudut pandang sensor terhadap pemanas, dan orientasi meja kerja alat. Hasil dari pengujian jarak dan offset divalidasi dengan perhitungan teoritis dan simulasi numerik Fire Dynamics Simulation. Hasil dari pengujian memiliki tren yang sama dengan perhitungan teoritis dan simulasi Fire Dynamics Simulation. Hasil dari penelitian ini juga menunjukkan bahwa jarak dan sudut pandang benar berpengaruh terhadap fluks radiasi yang diterima. ......Heat transfer always occurs in the daily life of human beings and can be felt its benefits as well as disadvantages. Heat transfer itself is divided into three according to medium, namely conduction, convection, and radiation. One example of a case where there is a third process of heat transfer is the event of a fire in a room. During a fire, the heat from the fire will travel into the surrounding environment and affect the objects around it with radiation, conduction, and convection. Heat that travels through radiation certainly does not require a medium of delivery because the heat is traveled in the form of electromagnetic waves and can travel to a very long distance. Distance, view factor, and placement of an object will affect the amount of radiation to be received from the heat of fire. Therefore, to examine the effect of distance, the viewing factor and the placement of objects against radiation, writer designs a multi axis heat flux sensors. Instrument with multi axis heat flux sensors or by the name of a Multi Axis Radiometer will be designed which will then be tested to determine the results of the design. Instrument called Multi Axis because the workbench of the instrument can be rotated 90o. Testing of the apparatus will include the heating temperature, the distance of the sensor to the heater, the sensor offset to the heater, the viewing angle of the sensor to the heater, and the orientation of the workbench. The results of testing distance and offset are validated by the theoretical calculations and numerical simulations of Fire Dynamics Simulation. The results of the test have the same charts trend with the theoretical calculations and simulations of Fire Dynamics Simulation. The results of this study also indicate that the distance and point of view affect the received radiation flux."

"Dewasa ini banyak studi yang mempelajari tentang sistem kabut air, berbagai eksperimen dilakukan dengan berbagai tujuan, seperti yang telah dilakukan oleh Jean-Marie Buchlin (2005) yang mengkaji tentang pengaruh water mist sebagai perisai panas dari tangki penimbunan bensin, Y.Gao, P.Liu, S.S.Li, dan W.K.Chow (2009) membahas tentang pengaruh water mist terhadap sebuah lingkungan yang dipengaruhi oleh pool fire, dan juga interaksi water mist terhadap pool fire yang dilakukan oleh Wang Xishi, Liao Guangxuan, Yao Bin, dan Fan Weicheng (2000). Kajian tentang sistem tirai kabut air dalam suatu kompartemen api ini dimaksudkan untuk mengetahui sejauh mana pengaruh sistem tirai kabut air dalam menghalangi panas yang dihasilkan dari pool fire di dalam suatu ruangan. Penggunaan kabut air dalam penelitian ini tidak untuk pemadaman api secara langsung dengan menyemprotkan kabut air ke pusat nyala api melainkan sebagai penghalang panas yang berupa tirai kabut air dan diletakkan jauh dari sumber api. Penelitian ini menggunakan suatu model kompartemen berukuran 1m x 0,5m x 0,5m yang terbuat dari Calcium Silicad sebagai tempat terjadinya kebakaran dengan salah satu sisinya yang terbuka. Bahan bakar yang digunakan dalam penelitian ini adalah bensin premium sebanyak 8 ml yang ditempatkan pada suatu wadah dengan diameter 6.3 cm dengan tinggi 4.3 cm. Dalam penelitian ini dibahas tentang pengaruh penggunaan kabut air dalam suatu kebakaran ruangan seperti: perbandingan nilai heat flux dan perbandingan nilai temperatur ruangan dimana variasi data dilakukan dengan melakukan pengukuran nilai heat flux dan temperatur ruangan sebelum dan sesudah pengaplikasian kabut air. Transduser heat flux yang digunakan bertipe Schmidt-Boelter yang dimanufaktur oleh Medtherm Corporation dengan no.seri 64-10SB-20. Dari hasil pengujian penggunaan sistem kabut air dihasilkan suatu grafik temperatur dan heat flux dengan dan tanpa pengaplikasian kabut air. Data dan hasil grafik yang diperoleh dari hasil eksperimen akan dibandingkan dengan hasil simulasi dengan menggunakan FDS (Fire Dynamic Simulator) pada kondisi yang kurang lebih sama dengan eksperimen. ......In this recent years, a lot of study performed to know about water mist system, varied experiments with various objective are done, like Jean ?Marie Buchlin (2005) who studied about thermal shielding by spray water curtain to a storage tank fire, Y.Gao, P.Liu, S.S.Li, dan W.K.Chow (2009) studied about the effect of water mist to an evironment iduced by pool fire, and interaction of water mist to a pool fire by Wang Xishi, Liao Guangxuan, Yao Bin, dan Fan Weicheng (2000). A study about water mist curtain in a compartment fire is performed to know about the enclosure effect of the water mist curtain to suppress the heat from a pool fire in a compartment. In this research the water mist system isn?t designed to extinguish the fire directly by spraying it to the center of the fire but it is designed to be a barrier for the heat from the fire and it is placed far from the fire source. We used a compartment fire model (1m x 0,5m x 0,5m) that is made from Calcium Silicad as a place of fire case with one opened side. The fuel that is used in this research is gasoline with 8 mL of volume and the pool diameter is 6,3 cm and 4,3 cm height. The heat flux and the distribution of temperature are measured in condition before and after using watermist system. Heat flux transducer in this experiment is Schmidt-Boelter type manufactured by Medtherm Corporation with serial number 64-10SB-20. The result of the experiment shows a graphic of heat flux and temperature. The data and the graphic obtained are compared with the result from FDS (Fire Dynamic Simulator) with the same condition of the experiment."

"[Pada paper ini void fraction dari R-290 di investigasi. Penggunaan R-290 ditujukan untuk menggantikan R-22, dikarenakan R-22 memiliki nilai ODP (Ozone Depletion Potential) sebesar 0.05 dan nilai GWP (Global Warming Potential) sebesar 1700. Nilai void fraction dibutuhkan karena berhubungan dengan prediksi nilai dari jatuh tekanan, yaitu pada jatuh tekanan akibat akselerasi. Sehingga, merupakan suatu kebutuhan untuk melakukan studi komprehensif mengenai void fraction pada aliran didih dua fase pada pipa konvensional berdiameter dalam 7.6 mm. Data primer didapatkan dengan melakukan eksperimen pada kondisi: Fluida kerja R-290, pipa horizontal berdiameter dalam 7.6 mm, temperatur saturasi pada rentang 5 hingga 15ºC, fluks kalor pada rentang 9 hingga 20 kW/m2 dan fluks massa pada rentang 300 hingga 420 kg/m2.s. Hasil jatuh tekanan eksperimen yang di dapatkan kemudian dibandingkan dengan jatuh tekanan prediksi., In this present paper the void fraction of R-290 was investigated. The use of R-290 is to replace R-22, since R-22 has 0.05 Ozone Depletion Potential (ODP) and 1700 Global Warming Potential (GWP). The relevancy to obtain the void fraction was related to predict the value of pressure drop, especially accelerational pressure drop. Therefore, it is a necessity to conduct a comprehensive study about void fraction in two-phase flow boiling in conventional pipe with 7.6 mm inner diameter. To obtain the primary data, the experiment was conducted with the experimental conditions of R-290 working fluid, 7.6 mm inner diameter horizontal tube, 5 to 15ºC saturation temperature, 9 to 20 kW/m2 heat flux, and 300 to 420 kg/m2.s mass flux. The recent results of pressure drop were compared to some existing method of pressure drop calculations]"