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"This book comprises selected papers from the International Conference on Numerical Heat Transfer and Fluid Flow (NHTFF 2018), and presents the latest developments in computational methods in heat and mass transfer. It also discusses numerical methods such as finite element, finite difference, and finite volume applied to fluid flow problems. Providing a good balance between computational methods and analytical results applied to a wide variety of problems in heat transfer, transport and fluid mechanics, the book is a valuable resource for students and researchers working in the field of heat transfer and fluid dynamics."

"Fraktal adalah penggalan sebuah bentuk geometri yang bisa dibagi lagi menjadi bagian-bagian. Setiap bagian tersebut akan terlihat mirip dengan bentuk keseluruhannya. Derajat dari batas penggalan suatu fraktal disebut dimensi fraktal. Fraktal mempunyai tiga tingkat keserupaan diri: serupa diri secara persis, lemah dan statistic. Metode-metode yang dapat digunakan untuk perhitungan dimensi fraktal dapat digunakan: Metode Segitiga Planar, Covering Blanket, Flat Structuring Element dan Box-Counting. Aplikasi dari Fraktal analisis dapat digunakan dalam penentuan kualitas resapan bahan berserat. Pada penelitian ini analisis fraktal digunakan pada proses fingering yang terjadi pada aliran celah sempit dengan fluida non-newtonian dengan divariasikan pada lebar celah (b), sudut kemiringan (?), dan jarak heater (dT/dx). Dengan menggunakan software MATLAB akan didapatkan nilai dimensi fraktal (Df) yang digunakan untuk menganalisa penelitian yang dilakukan. Dari penelitian ini dihasilkan pola aliran karakteristik pada fluida non-newtonian dimana nilai dimensi fraktal menunjukkan pertumbuhan fingering yang terjadi pada waktu spesifik tertentu. Pada gradien negatif (dT/dx0) dan tanpa gradien (dT/dx=0). Selain itu didapatkan bahwa perbedaan sudut kemiringan dan lebar celah tidak mempengaruhi karakteristik fluida. Nilai t/t* terletak pada jangkauan 0.25 - 3.5 dan nilai Df terletak pada 0.8 - 2. Viskositas fluida menurun ketika terjadi kenaikan temperatur dan berhubungan dengan meningkatnya dimensi fractal (Df). Karakteristik fluida Newtonian dan non Newtonian berbeda. Dengan perbandingan antara dimensi fractal (Df) dan t/t*, nilai maksimal pada penelitian ini diperoleh pada fluida non Newtonian t/t* = 3.5 sedangkan pada fluida Newtonian dapat mencapai t/t* = 10 pada nilai Df yang sama.

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Fractal geometry is a fragment of a form which can be subdivided into parts. Each section will look similar (at least approximately) overall shape. Degrees from the boundary of a fractal fragment is called fractal dimension. Fractal self-similarity has three levels: self-similar precisely, weak and statistics. The methods can be used for the calculation of fractal dimension can be used: Method of Planar Triangle, Covering Blanket, Flat Structuring Element and Box-Counting. Application of Fractal analysis can be used in determining the quality of absorbing fibrous material.

In this study, fractal analysis is used to fingering processes that occurred in the narrow gap flow with non-Newtonian fluid with variation in gap width (b), inclination angle (?), and the distance between heater (dT / dx). By using MATLAB to obtain the fractal dimension (Df) used to analyze the research undertaken.

Results from this study resulted in the flow pattern characteristic of non-Newtonian fluid in which the value of fractal dimension shows the growth of fingering which occurs at a specific time. On the negative gradient (dT / dx 0) and without a gradient (dT / dx = 0). In addition it was found that the difference angle and width of the gap does not affect the characteristics of the fluid. The value of t / t * lies in the 0.25 range - 3.5 and Df value lies in the 0.8 - 2. Inversely proportional to fluid viscosity decreases with increasing temperature and is associated with increasing the fractal dimension (Df). Characteristics of Newtonian and non Newtonian fluids are different. By comparison between fractal dimension (Df) and t / t *, a maximum value in this study non-Newtonian fluid was obtained at the t / t * = 3.5, while in Newtonian fluids can reach the t / t * = 10 at the same value of Df."

"This book presents a set of new developments in the field of basic and applied research work on the physical and chemical aspects of heat and mass transfer phenomena in a porous medium domain, as well as related material properties and their measurements. The book contents include both theoretical and experimental developments, providing a self-contained major reference that is appealing to both the scientists and the engineers. At the same time, these topics will encounter of a variety of scientific and engineering disciplines, such as chemical, civil, agricultural, mechanical engineering, etc. The book is divided in several chapters that intend to be a short monograph in which the authors summarize the current state of knowledge for benefit of professionals."

"ABSTRACTInvestigasi karakteristik fluida dalam skripsi ini mempunyai tujuan untuk membuktikan bahwa fluida ice slurry dengan Freezing Point Depressant menggunakan Ethyl Alcohol etOH adalah fluida Non Newtonian tetapi belum diketahui jenisnya antara Pseudoplastic atau Dilantant. Percobaan dilakukan dengan mengukur Pressure Drop dan juga debit untuk nantinya dihitung hubungan antara shear stress dan shear strain untuk mendapatkan gradien power law index yang digunakan untuk mengkategorikan jenis dari fluida ini. Percobaan pertama dilakukan dengan pipa uji 1 inchi, variasi kecepatan 25-29 Hz dan variasi konsentrasi etOH 5, 7 dan 10 dalam 30 liter air menghasilkan rentang power law index n sebesar 1,04-,1,23. Lalu percobaan kedua menggunakan pipa uji inchi menghasilkan n sebesar 1,138-2,244 dan percobaan ketiga menggunakan pipa uji inchi menghasilkan n sebesar 1,7518-3,1. Dimana jika suatu fluida non newtonian mempunyai n>1 maka bisa dikategorikan fluida tersebut adalah fluida Non Newtonian bentuk Dilantant. Dan tipe ice slurry ini terbukti adalah fluida non newtonian bentuk Dilantant karena mempunyai rentang n>1.

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ABSTRACTInvestigation of fluid characteristics in this thesis has a purpose to prove ice slurry fluid with Ethyl Alcohol etOH as Freezing Point Depressant is categorized as Non Newtonian fluids but not known the type between Pseudoplastic or Dilantant. The experiments were performed by measuring Pressure Drop and also the flow rate to calculate the relationship between shear stress and shear strain to obtain the power law index gradient that used to categorize the type of non newtionian fluid. The first experiments were performed in 1 inch test tube, variation of pump speed 25 ndash 29 hz, and variation of freezing point depressants are 5, 7, and 10 etOH concentration in 30 liters of water solutions yielded power law index range of 1,04 ndash 1,23. The second experiments using 3 4 inch test pipe yielded power law index range of 1,138 2,244. And the third experiments using 1 inch test pipe yielded power law index range of 1,7518 ndash 3,1. If Non Newtonian fluid has n 1 then it can be categorized as Non Newtonian fluid, Dilantant form. And this type of ice slurry is prooved as a Non Newtonian fluid, Dilantant form because has range of power law index more than one n 1."

"The book provides an easy way to understand the fundamentals of heat transfer. The reader will acquire the ability to design and analyze heat exchangers. Without extensive derivation of the fundamentals, the latest correlations for heat transfer coefficients and their application are discussed. The following topics are presented, steady state and transient heat conduction, free and forced convection, finned surfaces, condensation and boiling, radiation, heat exchanger design, problem-solving. After introducing the basic terminology, the reader is made familiar with the different mechanisms of heat transfer. Their practical application is demonstrated in examples, which are available in the Internet as MathCad files for further use. Tables of material properties and formulas for their use in programs are included in the appendix. "