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"The flow behavior of fluids such as molten plastics, biological fluids, and paints is much more varied and complex than that of traditional Newtonian fluids. The role of numerical simulation in the study of such flows has increased tremendously over the past fifteen years, and the phenomena and numerical difficulties in complex flows have led to new and challenging mathematical questions. Studying such flows presents a host of problems, as well as opportunities for mathematical analysis, including questions of asymptotics, qualitative dynamics, and adequacy of numerical methods. Mathematical Analysis of Viscoelastic Flows presents an overview of mathematical problems, methods, and results relating to research on viscoelastic flows. This monograph is based on a series of lectures presented at the 1999 NSF-CBMS Regional Research Conference on Mathematical Analysis of Viscoelastic Flows. It begins with an introduction to phenomena observed in viscoelastic flows, the formulation of mathematical equations to model such flows, and the behavior of various models in simple flows. It also discusses the asymptotics of the high Weissenberg limit, the analysis of flow instabilities, the equations of viscoelastic flows, jets and filaments and their breakup, as well as several other topics."

"This book treats the numerical analysis of finite element computational fluid dynamics. Assuming minimal background, the text covers finite element methods; the derivation, behavior, analysis, and numerical analysis of Navier-tokes equations; and turbulence and turbulence models used in simulations. Each chapter on theory is followed by a numerical analysis chapter that expands on the theory. The chapters contain numerous exercises."

"Describes general mathematical modeling of viscoelastic materials as systems with fading memory. Discusses the interrelation between topics such as existence, uniqueness, and stability of initial boundary value problems, variational and extremum principles, and wave propagation. Demonstrates the deep connection between the properties of the solution to initial boundary value problems and the requirements of the general physical principles. Discusses special techniques and new methods, including Fourier and Laplace transforms, extremum principles via weight functions, and singular surfaces and discontinuity waves."

"Fluida lumpur mempunyai banyak jenis yang terdiri dari banyak campuran material dimana ditunjukan sebagai fluida non-Newtonion atau fluida viscoelastic. Tujuan penelitian ini adalah untuk menguji sifat-sifat kekentalan aliran dan membuat kurva aliran untuk lumpur lapindo brantas dengan menggunakan pipa bulat dan pipa spiral P/Di=4,3. Diameter tabung adalah 12.7 mm. tegangan geser dan gradient kecepatan didapatkan dengan perhitungan, dari data pengukuran variasi kecepatan aliran pada masing-masing gradient tekanannya. Nilai power low eksponen di dapat untuk masing-masing perubahan konsentrasi larutan lumpur. Hasil menunjukan kekentalan sesaat dari larutan Lumpur tidak proposional dengan tegangan geser dan gradient kecepatan tetapi berhubungan dengan model power law.

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Mud fluid have many type consisted of many material mixture, where as fluid of non-Newtonian or fluid viscoelastic. Target of this research is to test the nature of stream viscosity and make the stream curve for the mud of lapindo brantas by using circular pipe and spiral pipe P/Di = 4,3. Diameter is 12.7 mm. tension shift and gradient speed got with the calculation, from data of measurement of variation of stream speed at each its gradient pressure. Assess the power low exponent in earning to the each change of concentration of mud condensation. momentary result as viscosity from mud condensation don?t proposional with the tension shift and gradient speed but relating to model of power law."

"Interfacial fluid mechanics: a mathematical modeling approach provides an introduction to mathematical models of viscous flow used in rapidly developing fields of microfluidics and microscale heat transfer. The basic physical effects are first introduced in the context of simple configurations and their relative importance in typical microscale applications is discussed. Then, several configurations of importance to microfluidics, most notably thin films/droplets on substrates and confined bubbles, are discussed in detail. Topics from current research on electrokinetic phenomena, liquid flow near structured solid surfaces,evaporation/condensation, and surfactant phenomena are discussed in the later chapters."

"Indonesia sebagai negara dengan risiko gempa bumi yang besar memiliki permasalahan yang tinggi pada kerusakan bangunan gedung akibat gempa. Hal tersebut perlu diselesaikan dengan menggunakan teknologi tahan gempa, dimana secara umum teknologi tahan gempa yang digunakan adalah shearwall namun dibeberapa bangunan gedung dapat menggunakan peredam. Pada penelitian ini akan menganalisis penggunaan teknologi peredam gempa berjenis viscoelastic rubber damper yang diaplikasikan pada bangunan gedung SGLC FT UGM berbasis risiko pada pelaksanaan teknologi tersebut untuk meningkatkan kinerja biaya. Penelitian bermula dengan mengidentifikasi komparasi antara teknologi tahan gempa shearwall dan viscoelastic rubber damper dari berbagai aspek, menganalisis aktivitas yang memiliki tujuan dan sasaran pada pekerjaan viscoelastic rubber damper, serta risiko-risiko pada pekerjaan tersebut. Metode yang digunakan pada penelitian ini adalah studi literatur, arsip, validasi pakar, dan pengolahan statistik. Analisis data yang digunakan pada penelitian ini adalah analisis deskriptif dan pengujian statistik untuk mendapatkan risiko dominan pada pekerjaan viscoelastic rubber damper pada bangunan gedung.

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Indonesia as a country with a large earthquake risk has a high problem of damage to buildings due to earthquakes. This needs to be solved by using earthquake-resistant technology, where in general the earthquake-resistant technology used is shearwall, but some buildings can use dampers. This study will analyze the use of earthquake damper technology of the viscoelastic rubber damper type which is applied to the SGLC FT UGM building which has risks in the implementation of this technology to improve cost performance. The research begins by identifying the comparison between earthquake resistant shearwall technology and viscoelastic rubber damper from various aspects, analyzing activities that have goals and objectives in viscoelastic rubber damper work, as well as the risks involved in the work. The methods used in this research are literature studies, archives, expert validation, and statistical processing. Data analysis used in this study is descriptive analysis and risk statistical testing to get the dominant effect on the work of viscoelastic rubber dampers in buildings."

"Masalah polusi saat ini menjadi fokus utama dalam terjadinya global warming di dunia. Salah satu penyumbang utama dari polusi itu ada pada industri perkapalan. Penggunaan bahan bakar minyak yang masif oleh kapal diseluruh dunia, terutama kontainer dan tanker yang menyumbang 40% total polusi dunia. Salah satu cara untuk mengatasi masalah ini adalah peningkatan efisiensi bahan bakar dengan menggunakan metode lubrikasi udara untuk meningkatkan drag reduction dari kapal tersebut. Pada skripsi ini digunakan metode Winged Air Induction Pipe untuk melubrikasi bagian bawah kapal. Winged Air Induction Pipe adalah sebuah alat yang menggunakan foil pada bagian bottom kapal untuk menghasilkan bubble dengan memproduksi udara rendah pada bagian atas foil tersebut. Udara yang terhisap ini nantinya akan masuk melalui pipa yang selanjutnya akan terperangkap pada aliran dan menjadi bubble. Bubble inilah yang nantinya akan melubrikasi plat kapal dan meningkatkan drag reduction pada kapal tersebut. Pada penelitian sebelumnya telah dilakukan metode yang sama namun pembahasan terkait variasi konfigurasi chord length foil dan bagaimana pengaruh viscous resistance pada foil terhadap pembentukan bubble belum lah dibahas. Penelitian ini dilakukan secara numerikal dengan menggunakan ANSYS CFD-Fluent dengan menggunakan metode k-w (Shear Stress Transport). Dengan membandingkanya dengan penelitian secara eksperimental yang dilakukan sebelumnya didapat tingkat error sebesar 1,49%. Selain itu digunakan pula NACA 653-618 yang sama yang digunakan oleh penelitain sebelumnya dengan tambahan variasi panjang chord length. Pada akhir penelitian ini didapatkan bahwa terdapat tendensi dari viscous resistance terhadap variasi konfigurasi yang mempengaruhi besar daya yang disimpan. Pada akhirnya daya yang disimpan oleh alat hingga 6 %.

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Pollution is a main focus in the status quo of global warming. One of those main contributors is the shipping industry. Massive usage in fuel oil by the ship around the world, especially the container and tanker ship produce more than 40% of total world pollution. One of those methods to solve this is problem is increasing the efficiency of ship using air lubrication method by increasing the drag reduction of the ship.

In this research, we used the device called as Winged Air Induction Pipe (WAIP) to lubricate the bottom of the ship. This device used foil to create bubbles by making low pressure area in the upper area of the foil which will suck the atmospheric air through the pipe and trap those air inside the flow which will became bubbles.

In the previous research the same method has been done, but the explanation about how the various configuration of chord length and the effect of viscous resistance will affect the creation of the bubbles were not explained yet. In this research, we used numerical simulation by using ANSYS CFD-Fluent with k-w SST (Shear Stress Transport) method. At the end the error occured only 1,49 % compared with experimental research done by previous studies.

This research also used the same NACA 653-618 which has been used by previous study within the addition of variation of the chord length of the foil. At the end of the research, there is a tendency between viscous resistance and net power saving by the device, which is at 6% of total power saving."