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Abstrak :
ABSTRAK
Tesis ini akan membahas mengenai kemampuan mahasiswa Fakultas Teknik Mesin Universitas Indonesia angatan 2012 dalam menganalisa dinamika fluida pada sudu turbin uap yang terdapat pada Laboratorium Departemen Teknik Mesin Universitas Indonesia. Penulisan skripsi ini akan membahas mengenai analisa perhitungan jumlah energi yang terjadi sejak sesaat masuk nosel hingga kepada keluar turbin yang nantinya akan digunakan sebagai pembangkit listrik dengan superheater pemanas lanjut dan aspek variable beban pada turbin yang berbeda. Selengkapnya variable beban yang terdapat pada turbin ini di Laboratorium Departemen Teknik Mesin lantai 1, terdapat 4 jenis beban pada turbin. Namun perhitungan dan pengolahan data yang dilakukan dalam pembahasan skripsi ini hanya dibatasi untuk variable beban 350 watt dan 450 watt. Tujuan pembuatan skripsi ini adalah penulis mampu menjelaskan tentang instalasi sistem turbin uap, prinsip kerja pesawat penggerak mula bertenaga uap, menghitung potensial energi uap keseluruhan yang masuk turbin dan keluarannya dalam bentuk yang sudah dikonversi energi listrik , serta dapat menjelaskan diagram T-s dan membandingkan entalpi total sesaat masuk dan keluar turbin, dengan energi kinetik yang terjadi pada sudu turbin/nosel. Dari hasil perhitungan yang dilakukan pada skripsi ini akan didapatkan beberapa kesimpulan mengenai nilai efisiensi pada sudu turbin dan nilai efisiensi turbin dan generator.Kata kunci : Turbin Uap, Segitiga Kecepatan, Energi Kinetik, Efisiensi.

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ABSTRACT
This thesis will discuss the ability of students of Faculty of Mechanical Engineering, University of Indonesia Rear 2012 to analyze the fluid dynamics in the steam turbine blade contained in the Department of Mechanical Engineering Laboratory of the University of Indonesia. This paper will discuss the analysis of the calculation of the amount of energy going on since just sign up to the exit nozzle turbine, which will be used as a power plant with superheater heating up and variable aspects of different loads on turbines. variable load contained on this turbine at the Laboratory Department of Mechanical Engineering 1st floor, there are four types of loads on the turbine. However, calculations and data processing is done in the discussion of this paper is limited to a variable load of 350 watts and 450 watts. The purpose of making this paper is the authors were able to explain about the installation of steam turbine systems, the working principle of the best prime movers steam powered, calculate the potential energy of steam overall turbine inlet and output in the form of the already converted electrical energy , and can explain the T s diagram and comparing the enthalpy total moment in and out of the turbine, the kinetic energy that occur on turbine blades nozzle. From the results of calculations performed in this thesis will be obtained several conclusions regarding the efficiency of the turbine blade and the efficiency of the turbine and generator.Keyword Steam Turbine, Triangle Speed, kinetic energy, efficiency.

Abstrak :
This book addresses a range of basic and essential topics, selected from the author's teaching and research activities, offering a comprehensive guide in three parts: Statics, Kinematics and Kinetics. Chapter 1 briefly discusses the history of classical and modern mechanics, while Chapter 2, presents preliminary knowledge, preparing readers for the subsequent chapters. Chapters 3 to 7 introduce statics, force analysis, simplification of force groups, equilibrium of the general coplanar force group, and the center of the parallel force group. The Kinematics section (Chapters 8 to 10), covers the motion of a particle, basic motion and planar motion of a rigid body. Lastly, the Kinetics section (Chapters 11 to 14) explores Newton’s law of motion, theorem of momentum, theorem of angular momentum, and theorem of kinetic energy. With numerous examples from engineering, illustrations, and step-by-step tutorials, the book is suitable for both classroom use and self-study. After completing the course, students will be able to simplify complex engineering structures and perform force and motion analyses on particles and structures, preparing them for further study and research. The book can be used as a textbook for undergraduate courses on fundamental aspects of theoretical mechanics, such as aerospace, mechanical engineering, petroleum engineering, automotive and civil engineering, as well as material science and engineering.

Abstrak :
Metode cold spray adalah proses disposisi kecepatan tinggi dimana partikel kecil (1 - 50 _m) dalam keadaan padat dipadu dengan gas yang dipanaskan dan dipercepat hingga kecepatan supersonik. Adhesi partikel hanya disebabkan oleh energi kinetik pada saat tumbukan. Proses ini menggunakan kecepatan tinggi ketimbang temperatur tinggi untuk menghasilkan coating, dan karenanya mengurangi reaksi-reaksi yang tidak menguntungkan dari proses thermal spray. Serbuk aluminium dengan kemurnian 99.9 % disemprotkan dengan metode cold spray pada tiga jenis substrat yang berbeda; paduan magnesium ZE41A-T5, paduan AA7075 dan baja 4130. Kemudahan untuk permulaan deposisi partikel coating sangat bergantung pada karakteristik substrat. Oleh karena itu pada penelitian ini dilakukan karakterisasi cold spray coating pada ketiga substrat untuk mempelajari pengaruh karakteristik substrat pada kualitas ikatan antara substrat dan coating. Karakterisasi dilakukan dengan pengamatan struktur mikro, dan kekerasan mikro yang difokuskan pada daerah antar muka. Hasil penelitian ini menunjukkan bahwa: (i) terbentuk lapisan Al2O3 pada daerah antar muka ketiga sampel; (ii) coating pada substrat paduan Mg memiliki kekerasan tertinggi dan persentase porositas terendah, yang dapat menunjukkan ikatan antar substrat dan coating yang berkualitas baik; (iii) mekanisme ikatan yang mungkin terjadi adalah penguncian secara mekanis (mechanical interlocking).

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Abstract: Cold spray is a recent development by which a high-rate deposition process of small particles in solid state are mixed with heated gas and accelerated to supersonic velocities through a nozzle. The particles impact the target surface with sufficient kinetic energy to cause plastic deformation and consolidation with the substrate material to bond together, rapidly building up a layer of deposited material. This process uses high velocity rather than high temperature to produce coatings, and thereby minimize many disadvantages of high temperature reactions, which are characteristics of typical thermal sprayed coatings. Aluminium powder of 99.9 wt. % purity has been sprayed by using cold spray method onto a range of substrates; which are ZE41A-T5 magnesium alloy, AA7075 aluminium alloy and 4130 steel. The ease of initiation of deposition depends critically upon substrate type. Hence, this research was carried out to characterize the substrate materials and investigate the possible bonding mechanism at the interface. It was concluded that the possible mechanism of bonding is mechanical interlocking, which is supported by the evidence that the interface at the entire samples is not a straight line that may due to generation of interface curvature. It was also observed that 1 ' 2 _m thickness of Al2O3 layer has formed at the interface of all samples, which due to the reaction of aluminum particles with oxygen.

Abstrak :
This book gives a mathematical insight--including intermediate derivation steps-into engineering physics and turbulence modeling related to an anisotropic modification to the Boussinesq hypothesis (deformation theory) coupled with the similarity theory of velocity fluctuations. Through mathematical derivations and their explanations, the reader will be able to understand new theoretical concepts quickly, including how to put a new hypothesis on the anisotropic Reynolds stress tensor into engineering practice. The anisotropic modification to the eddy viscosity hypothesis is in the center of research interest, however, the unification of the deformation theory and the anisotropic similarity theory of turbulent velocity fluctuations is still missing from the literature. This book brings a mathematically challenging subject closer to graduate students and researchers who are developing the next generation of anisotropic turbulence models.

Abstrak :
Kendaraan listrik merupakan sebuah perkembangan teknologi pada bidang otomotif untuk mengatasi permasalahan energi fosil yang semakin menipis di bumi. Energi akibat pengereman konvensional pada kendaraan sebagian besar terbuang menjadi energi panas sehingga diperlukan strategi pengereman yang optimal. Pengereman regeneratif merupakan mekanisme pengembalian energi yang terbuang saat proses pengereman. Pada pengereman regeneratif energi kinetik diubah menjadi energi listrik dengan bantuan generator. Metodologi yang digunakan pada penelitian ini, yaitu melakukan pengujian pengereman regeneratif dengan variasi beban resistif yang dihubungkan pada generator arus searah. Beban yang digunakan sebesar 12 Ω, 18 Ω, 22 Ω, 30 Ω, 38 Ω, 56 Ω, 80 Ω, dan 100 Ω. Perbedaan beban resistif mempengaruhi jumlah energi listrik yang dihasilkan dan waktu yang dibutuhkan untuk melakukan pengereman. Semakin kecil nilai resistansi pada generator maka semakin besar energi yang dihasilkan dan waktu yang dibutuhkan untuk melakukan pengereman semakin cepat. ......Electric vehicles are a technological development in the automotive sector to overcome the problem of depleting fossil energy on earth. Most of the energy due to conventional braking on vehicles is wasted into heat energy, so an optimal braking strategy is needed. Regenerative braking is a mechanism to recover energy wasted during the braking process. In regenerative braking, kinetic energy is converted into electrical energy with the help of a direct current generator. The methodology used in this study is to test regenerative braking with variations in resistive loads connected to a generator. The loads used are 12 Ω, 18 Ω, 22 Ω, 30 Ω, 38 Ω, 56 Ω, 80 Ω, and 100 Ω. The difference in resistive load affects the amount of electrical energy generated and the time it takes to brake. The smaller the resistance value on the generator, the greater the energy produced and the time it takes to brake faster.