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"This paper present the results of modeling study of two dimensions turbulent flow in an expansion canal by using depth averaged K-E model....."

"A single phase, incompressible turbulent flow through a 90º pipe bend with/without guide vane conditions has been studied here. The present work deals with the numerical simulation to investigate the change in flow separation and velocity distribution at the downstream section due to the effect of the guide vane. The k-? turbulence model has been adopted for simulation purposes to obtain the results. After the validation of existing experimental and numerical results, a detailed study has been performed for three different Reynolds number and four different positions of the guide vane. The value of the Curvature ratio (Rc/D) has been considered as one factor for the present study. The curvature ratio can be defined as the ratio between the bend curvature radius and hydraulic diameter of the pipe. The results obtained from the present study have been presented in graphical form. A flow separation region has been found at the bend outlet for flow through 90º pipe bend without the guide vane. This flow separation region was absent for the cases which dealt with the flow through 90º pipe bend with the guide vane. Velocity distribution at four different downstream positions for different cases and different Reynolds numbers have been compared and reported in the present study."

"Skripsi ini membahas mengenai Pengurangan Koefisien Gesek Larutan PEG 4000 800 PPM, 1000 PPM, 1200 PPM. Eksperimen ini menggunakan pipa bulat acrylic berdiameter luar 12,7 mm dan diameter dalam pipa 11 mm pada aliran Turbulen. Aliran dalam pipa tersebut diuji dengan menambahkan Larutan PEG 4000 kedalam air murni pada konsentrasi 800 ppm, 1000 ppm dan 1200 ppm dengan aliran Turbulen. Dari hasil data, tabel, dan grafik menunjukkan bahwa dengan penambahan Larutan PEG 4000 pada konsentrasi 800 ppm, 1000 ppm, dan 1200 ppm kedalam air murni terjadi Drag Reduction. Dari hasil data eksperimen penambahan dengan konsentrasi 800 ppm Larutan PEG 4000 yang dicampurkan kepada air murni dapat menurunkan koefisien gesekan sebesar 16,7 % pada f 12 dan 18,5 % pada f 23, sedangkan dengan konsentrasi 1000 ppm Larutan PEG 4000 dapat menurunkan koefisien gesekan sebesar 17,4 % pada f 12 dan 18,9 % pada f 23, dan dengan konsentrasi 1200 ppm Larutan PEG 4000 dapat menurunkan gesekan sebesar 19,2 % pada f 12 dan 19,8 % pada f 23 dengan Bilangan Reynold 21.222.

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This thesis discusses about Reduction Coefficient of Friction with solution of PEG 4000 with concentration of 800 PPM, 1000 PPM, 1200 PPM. This experiment uses a round acrylic tube outer diameter 12,7 mm and 11 mm inner diameter of the pipe in Turbulent flow. The flow in the pipe tested by adding a solution of PEG 4000 into pure water at a concentration of 800 PPM, 1000 PPM and 1200 PPM with a Turbulent flow. From the data, tables, and graphs show that with the addition of PEG 4000 solution at a concentration of 800 PPM, 1000 PPM, and 1200 PPM into pure water occurs Drag Reduction. From the experimental data with the addition of concentrations 800 PPM solution of PEG 4000 are mixed to pure water can decrease the friction coefficient of 16,7 % at f 12 and 18,5 % at f 23, while a concentration of 1000 PPM solution of PEG 4000 can reduce the coefficient of friction 17,4 % at f 12 and 18,9 % at f 23, and a concentration of 1200 PPM solution of PEG 4000 can reduce friction by 19,2 % at f 12 and 19,8 % at f 23 with Reynold's Numbers 21.222."

"This is the proceedings of the Second International Workshop on Flow Induced Noise and Vibration (FLINOVIA), which was held in Penn State, USA, in April 2016. The authors’ backgrounds represent a mix of academia, government, and industry, and several papers include applications to important problems for underwater vehicles, aerospace structures and commercial transportation. The book offers a valuable reference guide for all those working in the area of flow-induced vibration and noise.Flow induced vibration and noise (FIVN) remains a critical research topic. Even after over 50 years of intensive research, accurate and cost-effective FIVN simulation and measurement techniques remain elusive. This book gathers the latest research from some of the most prominent experts in the field.The book describes methods for characterizing wall pressure fluctuations, including subsonic and supersonic turbulent boundary layer flows over smooth and rough surfaces using computational methods like Large Eddy Simulation; for inferring wall pressure fluctuations using inverse techniques based on panel vibrations or holographic pressure sensor arrays; for calculating the resulting structural vibrations and radiated sound using traditional finite element methods, as well as advanced methods like Energy Finite Elements; for using scaling approaches to universally collapse flow-excited vibration and noise spectra; and for computing time histories of structural response, including alternating stresses."

"Proses pencampuran pupuk dan air sangat penting dalam pertanian jagung dan padi. Untuk memenuhi kebutuhan campuran pupuk dan air dalam skala besar dan konstan, diperlukan sistem pencampuran dengan memanfaatkan aliran turbulen. Alat yang dapat digunakan yaitu gabungan antara nozel jet dan pipa venturi. Interaksi antara kedua alat ini dalam mencampurkan pupuk dan air perlu dianalisa. Analisa dilakukan dengan simulasi computational fluid dynamics (CFD). Tujuan dari studi ini adalah untuk menganalisa akibat dari posisi nozel jet di dalam pipa venturi terhadap proses pencampuran pupuk dan air. Simulasi numerik dilakukan dengan model multifasa dan sifat termofisik konstan. Bentuk sistem yaitu pipa venturi klasik berdasarkan standar ISO 5167-4 2003 dengan nozel jet dipasangkan pada salah satu diantara dua posisi. Simulasi dilakukan dalam kondisi turbulen model Eulerian k-epsilon. Variasi simulasi dilakukan dengan beberapa kecepatan aliran masuk air dan pupuk dengan fraksi volume kedua fluida konstan. Hasil yang didapatkan adalah bahwa kedua geometri memiliki pola dispersi pupuk yang berbeda. Variasi fraksi volume pupuk pada kedua geometri berada pada rentang 0,18% hingga 1,79%. Kata Kunci: Pertanian, Pencampuran, CFD, Fraksi Volume, Pupu

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Water and fertilizer mixing is very important in paddy and corn agriculture. To fulfill a large and constant amount of fertilizer-water mixture, it requires a mixing system that utilizes turbulent flow. The tools that will be used are a combination of jet nozzle and venturi pipe. The interaction of these tools in fertilizer-water mixing need to be analyzed. The analysis will be done with CFD simulations. The goal of these study us to analyze the effect of jet nozzle position in venturi pipes against fertilizer-water mixing process. Numerical simulation is proceeded with multiphase model and constant thermophysical properties. The system shape is a classic venturi pipe based on ISO 5167-4 2003 standards with nozzle jet placed in one of two positions. The simulation is running on Eulerian kepsion turbulence model. These simulations are varied with several water and fertilizer inlet flow rate with volume fraction of both fluids constant. The results that acquired are that both geometries have different fertilizer dispersion pattern which tends to be inversed. The fertilizer volume fraction on both geometries is appear in 0,18% to 1,79% interval."

"Pendekatan eksperimen dan model simulasi telah dilakukan untuk mengetahui perilaku partikel halus yang menempel pada lapisan cairan di dinding dalam aliran dua fase gas padat. Polimetil metaklirat dengan diameter 20 um dan 50 um digunakan pada pengukuran ini. Dengan menggunakan sistem pengumpan kontinyu, partikel halus dimasukkan dan dicampur dengan udara di dalam ducting. Eksperimen aliran dua fase dengan gas dan partikel halus padat dalam temperatur ruangan telah dilakukan untuk mengamati efek penempelan partikel yang menempel di dinding yang memiliki lapisan cairan dengan viskositas tinggi. Hasil percobaan menunjukkan bahwa kuantitas partikel melekat tergantung pada kecepatan pengumpanan partikel. Hasil model simulasi juga menunjukkan kecenderungan yang sama. Hubungan laju pengumpanan bermacam-macam partikel dan tingkat penangkapannya dibahas disini."

"Since B A Tom 's found out the drag reduction phenomena, which occurs in polymer solutions in1948 many studies, have been done for it because we can apply to the economizing energy system thephenomena. The drag reduction is the application of the turbulent modification of the flow and we canapply it for the turbulent flow region. We measured the turbulent pressure loss in the square ducts andcircular pipe flow of a guar gum solution by manometer, and found that the friction factor in the ductsflow ware expressed by Re. Pressure loss in ducts ware measured for various concentrations of guargum and various diameters of pipes in water to study the effect of the additive on drag reduction, It isfound that guar gum acts like other drag reduction polymer additives because it constant the frictionfactor in laminar regime, modify the transition to turbulent flow, and reduces the friction factor the fullyturbulent regime."

"Luminar flow and turbulent of dilute polymer guar gum (fatter) solutions in smooth and in rough pineswas studied This experiment use in 25.4 mm of diameter pipe (PVC), which roughened by (k) 0, 34. 0,8and 1, 59 mm roughness value of sand grain and 250, 500 and 1000 ppm for additive concentration. Theresults show that flow properties ore influenced by polymer addition and surface roughness. In thetransition and turbulent flow regime without additive the increasing of friction coefficient appeared to beeffcted by wall condition alone. Addition of polymer to water is effective for rough pipe. For examplewith addition of 1000 ppm of polymer reduced drag in k/D = 0,03 rough pipe by 24 percent at Reynoldsnumber 2 x 10 , whereas in 250 ppm addition tested drag was reduced only 5 percent"