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"This monograph is focused mostly on the exposition of analytical methods for the solution of problems of strong phase change. A new theoretical model is proved useful in describing, with acceptable accuracy, problems of strong evaporation and condensation. The book is the first to treat the problem of asymmetry for evaporation/condensation. A semi-empirical model for the process is proposed for purposes of practical calculation of the process of strong evaporation. The limiting schemes of the vapor bubble growth are analyzed. The thermo-hydrodynamic problem of evaporating meniscus of a thin liquid film on a heated surface is considered. A theoretical analysis of the problem of evaporation of a drop levitating over a vapor cushion is performed. The problem of vapor condensation upon a transversal flow around a horizontal cylinder is considered. "

"Dalam penelitian ini akan dibahas tentang perancangan alat uji aliran evaporasi dua fase dengan menggunakan kanal mini horizontal. Adapun alat ujinya terdiri atas bagian test section yang terbuat dari pipa stainless steel dengan diameter dalam 3 mm, diameter luar 5 mm dan panjang 1000 mm yang diberikan flux kalor yang seragam disepanjang pipa tersebut dengan mengalirkan arus listrik dan memberikan insulasi pada bagian luar test section untuk meminimalisasi kalor yang terbuang ke lingkungan. Dimana flux kalor yang diberikan pada test section besarnya dapat divariasikan mulai dari 5 kW/m2 s/d 15 kW/m2. Untuk perancangannya dilakukan perhitungan perhitungan terhadap berbagai komponen yang akan digunakan, serta menggunakan software pembantu perancangan CATIA V5R17, sebagai perencanaan alat uji yang akan dibangun. Alat uji ini terdiri dari be berapa komponen penting diantaranya adalah refrigerant kerja (R-22) Tube in tube Heat Exchanger sebagai penukar kalor, Test Section sebagai area yang diamati, dan Receiver tank yang digunakan untuk menampung refrigerant yang kemudian akan ditimbang menggun akan timbangan digital.

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In this study will be discussed about the design of test equipment evaporative twophase flow by using a mini horizontal channel. As for the test equipment consists of the test section is made of stainless steel pipe with a diameter of 3 mm, outer diameter 5 mm and length 1000 mm which provided a uniform heat flux along the pipe with a current of electricity and provide insulation on the outside of the test section to minimize the heat lost to the environment. Where the heat flux is given on a test section can be varied from 5 kW/m2 s / d 15 kW/m2. For the design made the calculation of the various components to be used, as well as using CATIA V5R17 software design assistant, as the planning of test equipment that will be built. This test tool consists of several important components of which are working refrigerant (R - 22) Tube in tube heat exchanger as a heat exchanger, Test Section as the observed area, and receiver tanks are used to accommo date the refrigerant, which then weighed using digital scales."

"Cold storage untuk kebutuhan biomedis disyaratkan dapat mencapai -80oC dan untuk itu digunakan sistem refrigerasi cascade (Tianing et al, 2002). Sistem refrigerasi cascade masih menggunakan refrigeran CFC dan HCFC. Campuran azeotropis karbondioksida dan ethane merupakan refrigeran alternatif yang menjanjikan. Studi simulasi dan eksperimen mengindikasikan campuran karbondioksida dan ethane mampu mencapai temperatur -80oC (Darwin et.al, 2008). Namun demikian, temperatur minimum tersebut masih belum stabil. Hal ini diduga karena pengaruh temperatur evaporasi High Stage /HS yang tidak optimal dalam mngalirkan panas ke sistem Low Stage. Berdasarkan hal tersebut maka penelitian ini akan berkonsentrasi pada pengaruh temperatur evaporasi terhadap kerja sistem cascade dengan variasi pembebanan.

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AbstractCold storage for biomedical needs required to achieve-it's -80 ° C and used for cascade refrigeration system (Tianing et al, 2002). Cascade refrigeration system is still using CFC and HCFC refrigerants. Azeotropis mixture of carbon dioxide and Ethane is a promising alternative refrigerants. Simulation and experimental studies indicate a mixture of carbon dioxide and Ethane capable of reaching temperatures -80 ° C (Darwin et.al, 2008). However, the minimum temperature is still not stable. This is presumably because the effect of temperature evaporation Stage High / HS that is not optimal in transferring heat to Low Stage system. Based on these two studies will concentrate on the effect of temperature on the evaporation cascade system works with a variety ofloading."

"ABSTRAKTelah berhasil dibuat sebuah alat yang dapat berfungsi sebagai stasiunpenguapan/evaporasi otomatis yang telah terintegrasi dengan pengamatanparameter iklim lainnya yang berhubungan dengan proses evaporasi. Alat inidiberi nama ?Automatic Evaporation Station (AES)?, dengan kemampuanmengukur 6 (enam) parameter klimatologi seperti penguapan, suhu permukaanair, suhu udara, kelembaban udara, curah hujan dan kecepatan angin. Selain itualat AES ini juga dilengkapi dengan 2 (dua) buah sistem kontrol untukmempertahankan ketinggian air di Open Pan Evaporimeter agar tetap 5 cm daribibir panci (sesuai ketentuan dari World Meteorological Organization, WMO).Keberadaan AES ini dapat menggantikan sistem pengamatan penguapankonvensional yang masih dilakukan oleh Badan Meteorologi Klimatologi danGeofisika (BMKG), atau dapat pula digunakan untuk menggantikan stasiun hujankerjasama yang dimiliki BMKG. Pengantian stasiun hujan kerjasama denganstasiun evaporasi otomatis diharapkan akan lebih bermanfaat bila ditinjau darisegi biaya, kemudahan pengoperasian, jumlah parameter klimatologi yang dapatdiukur dan tingkat keakurasian data yang tetap terjaga walau diamati olehpetugas/observer yang tidak memiliki latarbelakang pendidikan khusus dibidangmeteorologi/klimatologi."

"Laju penguapan tetesan bahan bakar yang disemprotkan pada ruang bakar penting untuk diketahui pada proses pembakaran. Banyak penelitian dilakukan untuk melakukan simulasi pada ruang bakar dengan menggunakan software DNS atau atau OpenFoam. Simulasi pada software DNS dan OpenFoam menerapkan analogi Ranz-Marshall dengan pendekatan film stagnan untuk mendapatkan laju penguapan bahan bakar. Penelitian ini dilakukan untuk mengetahui apakah model analogi ini dapat digunakan pada tetesan premium yang memiliki bilangan Lewis 3,6 dan membandingkan dengan model modifikasi E. A. Kosasih.Metode penelitian ini menggunakan jarum suntik untuk membuat tetesan bahan bakar yang diletakkan pada termokopel. Kemudian dialirkan udara dengan variasi kecepatan pada temperatur 50ºC dan 75ºC. Setelah dianalisa akan didapat hubungan antara bilangan Reynold (Re), Prandtl (Pr), Schmidt (Sc), Nusselt (Nu) dan bilangan Sherwood (Sh). Model Modifikasi oleh E. A. Kosasih ternyata mempunyai korelasi yang lebih kuat dibandingkan dengan model film stagnan.

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Fuel droplet evaporation rate sprayed in combustion chamber is important to know for combustion process. The simulation in combustion chamber in many research use DNS or Open Foam software. The simulation using DNS and OpenFoam apply analogy of Ranz-Marshall with model of stagnant film approach as basis for calculating fuel evaporation rate. This study aimed to see whether the analogy model can be used on premium which has Lewis numbers 3,6 and compare with model modification (E.A Kosasih).

This research is using a nozzle to results fuel droplet on thermocouple. Afterward the air is given with variations of velocity at temperature range 50ºC and 75ºC. After being analized, the relations between Reynold number (Re), Prandtl (Pr), Schmidt (Sc), Nusselt (Nu) and Sherwood number (Sh) will be found. The value of Sherwood and Nusselt number with modification model has stronger correlation than stagnant film model."

"Isolated atoms in group II-B such as zinc (Zn),cadmium (Cd), and mercury (Hg) are chemicallystable. These atoms are important in the formation of excimer. Zinc in particular has beeninvestigated by many researchers, as Zn2excimer holds promise because of its long lifetime andits potential as an energy-storage system. However, excimer?s benefits are based on excitationof the outermost electron. Our study confirmed the quantumdynamical condensation processesin which inner-core excitation arises due to ion-recombination between the vapor phase and thesolid phase. The X-ray diffraction of the condensedstructure of zinc film had included strongdiffuse scattering depending on theincident energies. In this research, we produced the excitedstate of zinc excimer characterized by an extremely long lifetime.Intriguingly, a feature of thezinc film is that it transformsfrom metallic to insulative. It is thought thatsuch a structure withthis characteristic has been affected by electron spin and atomic distortion by inner-coreexcitation. The structure obtained in our experiment is expected to prove promising inengineering applications, such as electronics, spintronics, and batteries."

"Kami telah membahas fungsi partisi dari kondensasi Bose-Einstein di dalam perangkap parabola yang dinyatakan oleh persamaan Gross-Pitaevskii satu dimensi. Fungsi partisi itu sendiri dirumuskan hanya dengan meninjau semua tingkat-tingkat energi dari osilator kuantum makroskopik yang mirip seperti di dalam mekanika statistika. Solusi-solusi dari tingkat-tingkat energi untuk kasus ini dapat diturunkan dengan mengikuti metode yang menggunakan teori perturbasi bebas waktu. Pada kasus ini, persamaan Gross-Pitaevskii satu dimensi dapat diperlakukan sebagai osilator kuantum makroskopik dengan menerapkan kondisi bahwa faktor nonlinearnya sangat kecil. Selain itu, perumusan analitik untuk energi tingkat dasar dapat diperoleh dengan menggunakan metode tersebut. Namun demikian, tingkat-tingkat eksitasinya tidak diberikan secara eksplisit. Saat ini, kami melanjutkan pekerjaan sebelumnya untuk menurunkan tingkat-tingkat keadaan lainnya supaya dapat merumuskan fungsi partisi. Akan tetapi, kami tidak mendapatkan bentuk analitik dari fungsi partisi karena integral dari suku-suku nonlinear tidak dapat membentuk hubungan rekursif. Akibatnya, tidak hanya fungsi partisi tetapi juga energi bebas Helmholtz dan entropi harus dikaji ulang untuk memeriksa sifat konvergennya.

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We have discussed the partition function of the Bose-Einstein condensation in parabolic trap associated to the one-dimensional Gross-Pitaevskii equation. The partition function itself is constructed by considering all the energy levels of the macroscopic quantum oscillator which is similar to statistical mechanics. The solutions of the energy levels for this case can be derived by pursuing the method that applies the time-independent perturbation theory. In this case, the one-dimensional Gross Pitaevskii equation can be treated as the one-dimensional macroscopic quantum oscillator on condition that the nonlinearity is very small. Moreover, the analytical expression for the ground state energy can be obtained by applying the method. However, the higher level states were not explicitly provided. In this research we followed up on the former work to derive explicitly the other states in order to formulate the partition function. However, we did not find the closed form of the partition function since the results of nonlinear term integral could not form the recursion relation. As a consequence, not only should the partition function but also the Helmholtz free energy and entropy should be reevaluated to check their convergences. "

"The high temperatures generated in gases by shock waves give rise to physical and chemical phenomena such as molecular vibrational excitation, dissociation, ionization, chemical reactions and inherently related radiation. In continuum regime, these processes start from the wave front, so that generally the gaseous media behind shock waves may be in a thermodynamic and chemical non-equilibrium state. This book presents the state of knowledge of these phenomena. Thus, the thermodynamic properties of high temperature gases, including the plasma state are described, as well as the kinetics of the various chemical phenomena cited above. Numerous results of measurement and computation of vibrational relaxation times, dissociation and reaction rate constants are given, and various ionization and radiative mechanisms and processes are presented. The coupling between these different phenomena is taken into account as well as their interaction with the flow-field. Particular points such as the case of rarefied flows and the inside of the shock wave itself are also examined. Examples of specific non-equilibrium flows are given, generally corresponding to those encountered during spatial missions or in shock tube experiments."