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"This book deals with rotordynamics of automotive turbochargers while encompassing the analysis of the dynamics of rotating machines at very high rotor speeds of 300,000 rpm and above. This interdisciplinary field involves 1. thermodynamics and turbo-matching knowledge to compute working conditions of turbochargers, 2. fluid and bearing dynamics to calculate various operating thrust loads and to design the rotating floating ring bearings (two-oil-film bearings), and 3. tribology to improve the rotor stability and to reduce the bearing friction. Mathematical background in modeling and simulation methods is necessary; however, the prerequisites have been kept to a minimum. The book addresses both practitioners working in the field of rotordynamics of automotive turbochargers and graduate students in mechanical engineering. "

"Mikroalga sangat potensial untuk dijadikan sebagai bahan baku berbagai produk komersil, namun terkendala dalam efisiensi produksi biomassa. Hal tersebut dapat ditingkatkan dengan mempelajari pencampuran di dalam fotobioreaktor melalui teknologi computational fluid dynamic (CFD). Dalam penelitian ini, fotobioreaktor pencahayaan dalam untuk kultivasi mikroalga dimodelkan secara 3 dimensi yang mencakup neraca momentum, neraca massa fasa cair dan fasa gas. Model divalidasi dengan data penelitian dari jurnal Pegallapati dan Nirmalakhandan (2012) untuk simulasi selama 8 hari dengan pengaturan parameter μmax dan kd. Parameter μmax dan kd yang digunakan dalam model adalah sebesar 1,2 hari-1 dan 0,6 hari-1, dengan persen error hasil simulasi paling rendah 6,30% dan paling tinggi 38,64%. Hasil simulasi menunjukkan bahwa konsentrasi alga terus meningkat hingga 25,9 mol/m3 pada hari kedelapan, tidak berbeda jauh dengan hasil eksperimen sebesar 28,37 mol/m3. Profil konsentrasi alga cenderung untuk menyebar merata, menunjukkan adanya pencampuran di dalam reaktor. Hasil simulasi juga menunjukkan bahwa konsentrasi CO2 terlarut berkisar di angka -1 x 10-4 mol/m3 dan 1 x 10-4 mol/m3 pada 4 hari pertama serta di angka -1 x 10-17 mol/m3 dan 1 x 10-16 mol/m3 di 4 hari selanjutnya, menunjukkan adanya kenaikan kemampuan fiksasi CO2. Persebaran konsentrasi CO2 terlarut cenderung mengikuti perpindahan massa CO2 dari fasa gas ke fasa cair.

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Microalgae have many potential as raw material for several commercial products, but still lacking in biomass production efficiency. The efficiency can be increased by studying mixing phenomena in photobioreactor using computational fluid dynamics (CFD) technology. In this research, an internally-illuminated bubble column photobioreactor is modeled in 3 dimensions which consist of momentum balance and mass balance in gas and liquid phase. The model is validated using experimental data from Pegallapati and Nirmalakhandan (2012) for eight days of cultivation with an adjustment in μmax and kd value. The model is using μmax value of 1.2 d-1 and kd value of 0.6 day-1 which has an error percentage of 6.30% at the lowest and 38.64% at the highest compared to the experimental data. Simulation shows that algae concentration increases everyday and reaching the value of 25.9 mol/m3 in the eighth day, compared to 28.37 mol/m3 algae in the experiment. The algae concentration has a tendency to spread evenly throughout the reactor, showing that there is mixing in the reactor. Simulation also shows that dissolved CO2 concentration value is ranging from -1 x 10-4 mol/m3 to 1 x 10-4 mol/m3 in the first four days, while its value is ranging from -1 x 10-17 mol/m3 to 1 x 10-16 mol/m3 in the next four days, showing increase in CO2 fixation ability. Dissolved CO2’s concentration spreading tends to follow the spreading of CO2 mass transfer from gas phase to liquid phase.

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"The book develops a descriptive mathematical model articulated through continuum mechanics concepts for these non-Newtonian, viscoelastic fluids and turbulent flows. Each complex fluid and flow is examined in this continuum context as well as in combination with the turbulent flow of viscoelastic fluids. Some details are also explored via kinetic theory, especially viscoelastic fluids and their treatment with the Boltzmann equation. Both solution and modeling strategies for turbulent flows are laid out using continuum concepts, including a description of constructing polynomial representations and accounting for non-inertial and curvature effects."

"In many plants, vibration and noise problems occur due to fluid flow, which can greatly disrupt smooth plant operations. These flow-related phenomena are called flow-induced vibration.This book explains how and why such vibrations happen and provides hints and tips on how to avoid them in future plant design.The world-leading author team doesn?t assume prior knowledge of mathematical methods and provides the reader with information on the basics of modeling.The book includes several practical examples and thorough explanations of the structure, the evaluation method and the mechanisms to aid understanding of flow-induced vibrations."

"Sebagai salah satu sumber energi terbarukan generasi ke-tiga, mikroalga dapat menjadi alternatif solusi krisis energi nasional. Dalam skala industri, pembuatan fotobioreaktor kolom gelembung untuk kultivasi mikroalga sangat sulit dan cukup mahal. Oleh karena itu, pada penelitian ini fotobioreaktor akan dimodelkan dan disimulasikan untuk menurunkan risiko kegagalan scale-up. Dalam penelitian ini, fotobioreaktor pencahayaan dalam untuk kultivasi mikroalga Nannochloropsis salina dimodelkan secara 2 dimensi aksisimetri yang mencakup neraca massa fasa cair dan fasa gas, serta pemodelan intensitas cahaya pada fotobioreaktor. Model telah divalidasi dengan data penelitian dari jurnal Pegallapati dan Nirmalakhandan (2012) selama 16 hari. Proses validasi dengan laju alir 800 mL/min dan konsentrasi gas CO2 masuk 0.5%, 1%, dan 2% berturut-turut memberikan persen deviasi rata-rata sebesar 5%, 12%, dan 4%. Hasil simulasi menunjukkan adanya pertumbuhan alga di dalam reaktor yang ditandai dengan kenaikan konsentrasi mikroalga, yakni dari 0.08 g/L pada hari pertama hingga 0.51 g/L pada hari ke 16. Hasil simulasi menunjukkan bahwa pertumbuhan mikroalga didalam fotobioreaktor dipengaruhi oleh konsentrasi CO2 terlarut, intensitas cahaya, konsentrasi nutrisi, dan suhu. Model yang valid kemudian disimulasikan dengan berbagai parameter, yang mencakup konsentrasi CO2, intensitas cahaya, suhu, tekanan, laju alir gas, konsentrasi nutrisi, perubahan tinggi, diameter, dan lebar sparger udara

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As one source of third generation renewable energy, microalgae can be an alternative solution to the national energy crisis. In the industry, the manufacturing of a bubble column photobioreactor for cultivation is very difficult and quite expensive. Therefore, in this study photobioreactor will be modeled to reduce the risk of failure to scale-up. An internal illuminated photobioreactor is modeled in two dimensiona asymmetry which also includes mass balance in both liquid phase and gas phase, as well as the light intensity model inside the photobioreactor. The model has been validated with research data from Pegallapati and Nirmalakhandan (2012) for 16 days of cultivation. The validation with 800 mL/min gas flow rate and the ratio of incoming CO2 gas 0.5%, 1% and 2% respectively have a percent of average deviation of 5%, 12%, and 4%. The simulation results showed the growth of algae in the reactor is marked by microalgae concentration, which is 0.08 g/L on the first day and become 0.51 g / L on the day 16. The distribution of dissolved CO2 rise rapidly during the first day until the concentration reached 0.775 mol / m3 and tended to decrease up to day 10 and returned an increase of up to 16 days. The microalgae growth is affected by the concentration of dissolved CO2, light intensity, the concentration of nutrients, and temperature. Then the valid model is simulated with some variety of parameters, which include CO2 concentration, light intensity, temperature, gas pressure, gas flow rate, nutrients concentration, the change in height, diameter, and the width of the air sparger"

"Renewable diesel atau bahan bakar diesel terbarukan adalah bahan bakar diesel alternatif yang dibuat dari hydrotreating minyak nabati dan memiliki struktur kimia yang sangat mirip dengan bahan bakar diesel konvensional, yaitu alkana rantai lurus C15-C18. Penelitian ini difokuskan pada pemodelan trickle-bed reactor skala besar untuk memproduksi renewable diesel melalui reaksi hydrotreating minyak nabati non-pangan dengan katalis NiMoP/Al2O3.Model yang dibuat adalah model trickle-bed reactor 2D axissymmetric berbentuk silinder tegak dengan diameter 1,5 m dan tinggi 6 m dengan mempertimbangkan perpindahan massa, momentum, dan energi di fasa gas, cair, dan padatan katalis. Reaktor yang dimodelkan berisi katalis berbentuk bola dengan diameter 1/8 inch, dengan kondisi operasi: tekanan 500 psig dan suhu umpan 325oC. Triolein dengan konsentrasi sebesar 5% wt di dalam pelarut dodekana diumpankan ke dalam reaktor sebagai fasa cair, dan hidrogen dengan perbandingan 188 mol hidrogen/ mol triolein diumpankan sebagai fasa gas. Kecepatan umpan gas masuk adalah sebesar 0,2 m/s.Hasil simulasi menunjukkan bahwa konversi minyak nabati (triolein) adalah sebesar 10,6%, yield produk sebesar 2,17% wt, dan kemurnian produk sebesar 2,14% wt. Untuk mencapai konversi dan kualitas produk yang lebih tinggi, simulasi lebih lanjut dilakukan dengan memvariasikan kecepatan gas umpan pada kondisi isotermal. Kondisi optimum yang diperoleh untuk reaktor isotermal adalah kecepatan gas umpan sebesar 0,005 m/s dengan konversi 99,1%, yield 81,7%, dan kemurnian produk 56,1% wt.

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Renewable diesel is an alternative fuel used in diesel engines which is mainly made from vegetable oils and has very similar chemical structure with fossil diesel fuel. Renewable diesel consists mainly of straight-chain alkanes in the range of diesel fuel (C15-C18). This research is focused on modeling a large-scale trickle-bed reactor to produce renewable diesel via non-edible vegetable oil hydrotreating with NiMoP/Al2O3 catalyst.

The two-dimensional axisymmetry of a non-isothermal vertical cylindrical trickle-bed reactor with the diameter of 1.5 m and the height of 6 m was modeled using computational fluid dynamics by considering mass, momentum, and energy transfer in gas, liquid and solid phases. The reactor is packed with spherical catalyst particles of 1/8-inch diameter under the the pressure of 500 psig and the inlet temperature of 325 oC. Triolein of 5% wt in dodecane is fed as liquid phase, and hydrogen of 188 mol hydrogen/triolein is fed as gas phase. The inlet gas velocity is 0.2 m/s.

The simulation results show that the vegetable oil (triolein) conversion is 10.6%, the product yield is 2.17% wt and the product purity is 2.14% wt. To achieve higher conversion and product quality, further simulation is conducted by varying the inlet gas velocity for isothermal condition. The optimum condition is reached at inlet gas velocity of 0.005 m/s, with 99.1% conversion, 81.7% wt yield, and 56.1% wt product purity."

"The research aims to scale up a small-scale stirred batch reactor to a large-scale stirred batch reactor in order to degum crude palm oil for use as a raw material in biodiesel production. The scale-up is based on the similarity of fluid Reynolds numbers in the two differently sized reactors. To achieve this aim, computational fluid dynamic modeling and simulations of the two reactors were performed. A small-scale palm oil degumming process was carried out in a 250 cc autoclave reactor using a magnetic stirrer at 500 rpm. The simulation results of this small reactor yielded a fluid Reynolds number in the range of 5 to 3,482. The large-scale reactor proposed in this research is 1.25 m3 in volume and is equipped with two impellers: a pitched blade impeller and a Rushton turbine impeller. The pitched blade impeller is placed over the Rushton turbine impeller. They are rotated at 100 rpm. Under this setting and operation, the resulting fluid Reynolds number was in the range of 486 to 202,000. This result indicates that the large-scale reactor was able to reproduce the reaction performance obtained in the small-scale reactor."

"Addresses external biofluiddynamics concerning animal locomotion through surrounding fluid media - and internal biofluiddynamics concerning heat and mass transport by fluid flow systems within an animal."

"This second edition, like the first, attempts to arrive as simply as possible at some central problems in the Navier-Stokes equations in the following areas: existence, uniqueness, and regularity of solutions in space dimensions two and three; large time behavior of solutions and attractors; and numerical analysis of the Navier-Stokes equations. Since publication of the first edition of these lectures in 1983, there has been extensive research in the area of inertial manifolds for Navier-Stokes equations. These developments are addressed in a new section devoted entirely to inertial manifolds. Inertial manifolds were first introduced under this name in 1985 and, since then, have been systematically studied for partial differential equations of the Navier-Stokes type. Inertial manifolds are a global version of central manifolds. When they exist they encompass the complete dynamics of a system, reducing the dynamics of an infinite system to that of a smooth, finite-dimensional one called the inertial system. Although the theory of inertial manifolds for Navier-Stokes equations is not complete at this time, there is already a very interesting and significant set of results which deserves to be known, in the hope that it will stimulate further research in this area. These results are reported in this edition. Part I presents the Navier-Stokes equations of viscous incompressible fluids and the main boundary-value problems usually associated with these equations. The case of the flow in a bounded domain with periodic or zero boundary conditions is studied and the functional setting of the equation as well as various results on existence, uniqueness, and regularity of time-dependent solutions are given. Part II studies the behavior of solutions of the Navier-Stokes equation when t approaches infinity and attempts to explain turbulence. Part III treats questions related to numerical approximation. In the Appendix, which is new to the second edition, concepts of inertial manifolds are described, definitions and some typical results are recalled, and the existence of inertial systems for two-dimensional Navier-Stokes equations is shown."

"The relatively recent increase in computational power available for mathematical modeling and simulation raises the possibility that modern numerical methods can play a significant role in the analysis of complex particulate flows. This introductory monograph focuses on basic models and physically based computational solution strategies for the direct and rapid simulation of flowing particulate media. Its emphasis is primarily on fluidized dry particulate flows in which there is no significant interstitial fluid, although fully coupled fluid-particle systems are discussed as well. An introduction to basic computational methods for ascertaining optical responses of particulate systems also is included.The successful analysis of a wide range of applications requires the simulation of flowing particulate media that simultaneously involves near-field interaction and contact between particles in a thermally sensitive environment. These systems naturally occur in astrophysics and geophysics; powder processing pharmaceutical industries; bio-, micro- and nanotechnologies; and applications arising from the study of spray processes involving aerosols, sputtering, and epitaxy."