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Abstrak :
Penelitian ini membahas tentang Bilangan Reynolds pada dua fasa dari hasil percobaan dengan refrigeran berbeda. Percobaan dilakukan pada kondisi perpindahan panas konveksi didih pada kanal mini horizontal dengan refrigeran R-290 dan R-600a. Test section terbuat dari pipa stainless steel dengan diameter dalam 3 mm, panjang 1000 mm dan dipanaskan secara merata di sepanjang pipa tersebut dengan heat flux divariasikan antara 5 kW/m2 sampai dengan 8 kW/m2. Dari penelitian didapat perubahan temperatur yang terjadi pada dinding dalam test section dengan metoda konduksi dan Nilai Reynolds number dibandingkan dengan kualitas Massa Uap. Fluktuasi Nilai Reynolds number menggambarkan kondisi aliran tiap fasa didalam test section. Dari hasil perbandingan dua Reynolds number untuk masing-masing refrigeran, Isobutana memiliki nilai Reynolds number lebih rendah dibandingkan dengan Propana pada kondisi mass flux dan heat flux yang relatif sama. Nilai Reynolds number ini selanjutnya akan digunakan untuk menentukan Chisolm Number dalam menghitung friction multiplayer. ......This study discusses the Reynolds Number of two phase flow in Horizontal Mini Channel. Experiments were performed on the convective boiling in Horizontal minichannel with R-290 and R600a. The test section was made of stainless steel tube with inner diameter of 3 mm, length of 1000 mm and it is uniformly heated along the tube with heat flux was varied from 5 kW/m2 up to 8 kW/m2. From the experiments, taken data was results the temperature of test section inner diameter and Reynolds Number of liquid phase and gas phase. The Reynolds Number represent flow of the two phases in test section. Comparison of Reynolds Number from the two refrigerant shows that Isobutana have better value than Propana since its Reynolds Numbers is lower than Propana in similar mass flux and heat flux condition. Based on the Reynolds Number, Chisolm Number will concluded to determine two phase friction multiplayer.

Abstrak :
Kerugian jatuh tekanan (pressure drop) memiliki kaitan dengan koefisien gesek dan merupakan hal penting dari sistem aliran fluida di dalam pipa karena berhubungan dengan penggunaan energi. Air murni merupakan salah satu dari fluida-fluida sederhana yang digunakan pada penelitian kerugian jatuh tekan. Air merupakan fluida newtonian dimana viskositasnya hanya berpengaruh oleh perubahan temperatur. Penelitian ini dilakukan untuk mengetahui kerugian jatuh tekan yang terjadi pada aliran fluida dengan penambahan serat abaca. Dari pengujian ini didapatkan data debit aliran, perbedaan ketinggian air, dan kecepatan aliran. Spesifikasi dari alat pengujian yang diperlukan juga didapatkan untuk diolah menggunakan persamaan-persamaan empiris sehingga didapatkan hasil pengolahan. Tampilan grafik hasil pengolahan akan dibandingkan dengan grafik secara teoritis. Grafik yang ditampilkan merupakan hubungan antara bilangan Reynolds dengan beda tekanan dan bilangan Reynolds dengan koefisien gesek. ......Pressure drop has a relevancy with the coefficient of friction and it?s significant case of the system of fluid rate in the pipeline cause it?s related with energy consumption. Pure water is one of plain fluids used on pressure drop research. Water is newtonian fluid which its viscosity depends on temperature change only. This research done in order to understand the pressure drop use abaca fibres. From the research obtains the capacity of rate, difference of water height, and velocity of rate. Specification of the equipment required is also getting to processing that uses empirical equations, so it will get the processing result. Processing result graphic will be compared with the theoritical graphic. The graphic being appeared is relation between Reynolds number with difference of pressure and Reynolds number with coefficient of the friction.

Abstrak :
ABSTRAK
Kerugian jatuh tekanan (pressure drop) memiliki kaitan dengan koefisien gesek dan merupakan hal penting dari sistem aliran fluida di dalam pipa karena berhubungan dengan penggunaan energi. Air murni merupakan salah satu dari fluida-fluida sederhana yang digunakan pada penelitian kerugian jatuh tekan. Air merupakan fluida newtonian dimana viskositasnya hanya berpengaruh oleh perubahan temperatur.

Penelitian ini dilakukan untuk mengetahui kerugian jatuh tekan dan karakteristik yang terjadi pada penampang pipa bulat dengan Æ sebesar 2mm, Bilangan Reynolds dan koefisien gesek. Aliran fluida memiliki karakteristik pokok (laminer atau turbulen). Nilai Bilangan Reynolds 2000-4000 menunjukan aliran laminer dan diatas nilai 4000 menunjukan turbulen. Nilai Bilangan Reynolds yang tinggi berarti ada kecepatan aliran yang tinggi, perluasan fluida dan viskositas yang kecil. Gesekan antara fluida dan dinding pipa dapat diabaikan karena yang digunakan adalah pipa mulus dan koefisien gesek adalah antara partikel fluida yang diam dan yang bergerak.

Dari pengujian ini didapatkan data debit aliran, perbedaan ketinggian air, kecepatan aliran dan viskositas fungsi temperatur. Spesifikasi dari alat pengujian yang diperlukan juga didapatkan untuk diolah menggunakan persamaanpersamaan empiris sehingga didapatkan hasil pengolahan, tampilan grafik hasil pengolahan yang akan dibandingkan dengan grafik secara teoritis. Grafik yang ditampilkan merupakan hubungan antara Bilangan Reynolds dan koefisien gesek dimana semakin kecil Bilangan Reynolds (laminer) maka akan semakin tinggi koefisien gesek. Perbedaan ketinggian air melalui alat ukur (manometer) juga menunjukan besar kecilnya kerugian energi tersebut. Semakin tinggi perbedaan ketinggian air antar tiap titik alat pengukur tekanan maka kerugian energi semakin besar.

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ABSTARCT
Pressure drop has a relavancy with the coefficient of friction adn it?s significant case of the system of fluid rate in the pipeline cause it?s related with energy consumption. Pure water is one of plain fluids used on pressure drop research. Water is newtonian fluid which its viscosity depends on temperature change only.

This research done in order to understand the pressure drop occurs at fluid rate and the characteristic from of round pipe with Æ = 2 mm, Reynolds Number and coefficient of friction. Fluid rate has a fundamental characteristic (laminar or turbulent). The value of Reynolds Number 2000 up to 4000 appears the laminar rate and more than 4000 for turbulent. High value of Reynolds Number appears high velocity of fluid rate, fluid expansion and low viscosity. Friction between the fluid and the pipe wall can be neglected because the pipe used in this research is a smooth pipe and friction is between static fluid and moving fluid.

From the research obtains the capacity of rate, difference of water height, velocity of rate and viscosity depended on temperature change. Specification of the equipment required is also getting to processing that uses empirical equations, so it will get the processing result, processing result graphic will be compared with the theoritical graphic. The graphic being appeared is relation between Reynolds Number and coefficient of the friction, where on teh wane of Reynolds Number (laminar), so then the coefficient of friction increased. A difference of water height through the measuring instrument (pressure gauge) also appears amount of losses. The higher a difference of water height inter each point of pressure gauge, so the losses become bigger.

Abstrak :
Transportasi merupakan salah satu hal yang berkaitan dengan pemanfaatan energi. Transportasi fluida pada sistem perpipaaan merupakan salah satu contohnya yang sering ditemui di Industri-industri besar. Pengurangan hambatan gesek diperlukan untuk menghemat energi pada transportasi di aliran dalam pipa. Tujuan dari penelitian ini adalah mencari karakter aliran dari penambahan ekstrak konjac pada air yang dialiri dalam pipa spiral dengan ratio pi/d 14.6 dan diameter hidrolis 6 mm serta pipa bulat berdiameter 4 mm dan 2 mm. Perhitungan hambatan gesek yang diinginkan didapatkan melalui perbedaan tekanan dari kedua pressure tap dengan jarak 0.9 meter. Perbedaan tekanan dihasilkan melalui variasi konsentrasi campuran 100 ppm, 200 ppm, dan 400 ppm serta lama pencampuran 15 menit dan 60 menit. Hasil eksperimen menunjukan bahwa Pressure drop terjadi pada setiap pipa uji, dan nilai pressure drop tersebut semakin menurun dengan adanya penambahan ekstrak konjac setiap konsentrasinya. Reynold Number pada pipa bulat spiral pada pengadukan 60 menit terkecil adalah 1609, terbesar adalah 11698, sedangkan Drag reduction terkecil adalah 12.94, terbesar adalah 49.33. ......Transportation is one of the things related to energy utilization. Fluid transport in pipe systems is one such example that is often encountered in large industries. Reduction of the frictional resistance is required to save energy on transport in the pipeline flow. The purpose of this research is to find the character of flow from addition of konjac extract to water which is flowed in spiral pipe with ratio of pi d 14.6 and diameter of hydraulic 6 mm and round pipe with diameter 4 mm and 2 mm. The calculation of the desired friction resistance is obtained through the pressure difference of the two pressure taps with a distance of 0.9 meters. The difference in pressure was generated through mixed concentration variations of 100 ppm, 200 ppm, and 400 ppm as well as mixing time of 15 minutes and 60 minutes. The experimental results show that the Pressure drop occurs in each test tube, and the pressure drop value decreases with the addition of conjac extract of each concentration. Reynold Number on spiral round pipe at 60 minute smallest stirring is 1609, biggest is 11698, while the smallest Drag reduction is 12.94, biggest is 49.33.

Abstrak :
Since B A Tom 's found out the drag reduction phenomena, which occurs in polymer solutions in 1948 many studies, have been done for it because we can apply to the economizing energy system the phenomena. The drag reduction is the application of the turbulent modification of the flow and we can apply it for the turbulent flow region. We measured the turbulent pressure loss in the square ducts and circular pipe flow of a guar gum solution by manometer, and found that the friction factor in the ducts flow ware expressed by Re. Pressure loss in ducts ware measured for various concentrations of guar gum and various diameters of pipes in water to study the effect of the additive on drag reduction, It is found that guar gum acts like other drag reduction polymer additives because it constant the friction factor in laminar regime, modify the transition to turbulent flow, and reduces the friction factor the fully turbulent regime.

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