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Analysis of Unsteady Squeezing Flows

Thesis Info

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External Link

Author

Qayyum, Mubashir

Program

PhD

Institute

National University of Computer and Emerging Sciences

City

Islamabad

Province

Islamabad

Country

Pakistan

Thesis Completing Year

2017

Thesis Completion Status

Completed

Subject

Mathemaics

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/13691/1/mubashir.qayyum.phd.thesis.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676725493077

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The squeezing flow occurs due to the action of normal stresses that originate from different configurations of the plates movement. This context may resound to be profoundly simple from the onset, but has important applications in the areas of engineering, physics, biology, and material sciences. In the past few years, the study of rheometric properties of fluids has garnered profound attention due to its vast industrial applications. Examples include modeling of lubrication systems involved in squeezing of fluids, compression and injection molding processes of metals and polymers, hydrodynamical tools and machines, modeling of chewing and eating, and modeling of the functions of heart valves and blood vessels. As a result, it is a major focus of researchers working in fluid mechanics. This thesis presents the theoretical analysis of unsteady squeezing flow of Newtonian and nonNewtonian fluids between two parallel plates under various boundary conditions. Observation of the squeezing behavior and associated rheological properties of the fluid can be interpreted using various analytical and numerical techniques. Due to the simplicity of the geometry involved, these can also be realized experimentally, while obtaining measurements from sensors or feedback control loops. For the analytical and numerical approach, the squeeze behavior is based on various models like Newtonain, Casson, Power law etc which leads to various differential equations. For this purpose, the thesis goes into a detailed investigation of the rheological properties of fluid flow with various boundary conditions and fluid types. These properties include velocity profiles, pressure distribution, and skin-friction. This investigation starts initially with the analysis of an unsteady flow of Newtonian fluid squeezed between two circular plates with slip and no-slip at the boundaries. It then gradually extends to higher order problems and different boundary conditions. This includes firstly a case involving squeezing of an incompressible Newtonian fluid passing through porous medium, followed by another case involving squeezing of non-Newtonian Casson fluid having magnetohydrodynamical effect, and passing through porous medium. The Casson fluid model is further extended to analyze the slip effect at fluid-solid interface. All these cases are dealt in separate chapters. In all cases, similarity transformations are used for the conversion of PDEs to highly nonlinear ODEs. Various analytical techniques like Optimal Homotopy Asymptotic Method (OHAM), Homotopy Perturbation Method (HPM), Homotopy Perturbation Laplace Method (HPLM), and numerical schemes like Explict and Implicit Runge Kutta Method of order 4 (ERK4 & IRK4) and NDSolve (Mathematica Solver) are applied for the solution and analysis of the modeled problems. Convergence and validity of the obtained analytical solutions are checked by finding various order solutions along with residual errors, and comparing it with numerical results. In addition, the thesis also proposes a novel adaptation to a scheme that combines tradiiii tional perturbation techniques with Homotopy using a Laplace transform. This scheme is applied to a problem of squeezing flow of an incompressible Newtonian fluid through porous medium, and tested against various analytical and numerical schemes.
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خالد مسعود

آہ جناب خالد مسعود!!
یہ خبر علمی و دینی خصوصاً ترجمان القرآن مولانا حمید الدین فراہیؒ کے قدردانوں اور ان کے علوم و افکار کے شیدائیوں کے لیے بڑی غم ناک اور روح فرسا ہے کہ یکم اکتوبر ۲۰۰۳؁ء کو رسالہ تدبر لاہور کے مدیر جناب خالد مسعود صاحب کا انتقال ہوگیا، اناﷲ وانا الیہ راجعون۔
وہ مولانا امین احسن اصلاحی کے شاگرد رشید اور علمی وارث و جانشین تھے، انہوں نے اپنی زندگی فکر فراہی کی شرح و ترجمانی اور اس کی ترویج و اشاعت کے لیے وقف کردی تھی، ان کی وفات سے ہم قرآن و حدیث کے ایک بڑے خدمت گزار سے محروم ہوگئے۔
مرحوم کو جگر کی بیماری تھی، خون کی رگ بار بار پھٹ جاتی تھی اور خون کی قے ہونے لگتی تھی، آخر اس بیماری نے ان کا کام تمام کردیا۔
خالد مسعود صاحب ضلع جہلم کے ایک گاؤں ’’ﷲ‘‘ ۱۶؍ دسمبر ۱۹۳۵؁ء کو پیدا ہوئے، یہیں ابتدائی تعلیم حاصل کی اور ۱۹۵۱؁ء میں نوشہرہ سے فرسٹ ڈویژن میں میٹرک اور ۱۹۵۵؁ء میں اسلامیہ کالج لاہور سے فرسٹ ڈویژن میں بی۔ایس۔سی کیا، ۱۹۵۷؁ء میں پنجاب یونیورسٹی سے کیمسٹری میں ایم۔ایس۔سی کیا، ۱۹۵۸؁ء میں انڈسٹریل ریسرچ لیبارٹریز سے وابستہ ہوئے پھر مزید تعلیم کے لندن گئے اور ۱۹۵۹؁ء میں وہاں کے کنگز کالج سے کیمیکل انجینئرنگ میں ڈپلوما حاصل کیا، واپسی کے بعد ۱۹۷۴؁ء میں پنجاب یونیورسٹی سے علوم اسلامیہ میں ایم۔اے کیا، ۱۹۸۵؁ء میں قائداعظم لائبریری میں ملازمت کی، اس ے وابستگی کے زمانے میں بچوں کے لیے آسان زبان میں متعدد مفید اور معلوماتی کتابیں تحریر کیں، جو بہت مقبول ہوئیں اور بعض پر ان کو ایوارڈ بھی ملا، گو ان کتابوں میں فلکی طبعیات کی جدید ترین تحقیقات کے نتائج اور کائنات کے بارے میں نئے افکار و نظریات پیش کیے گئے ہیں تاہم اسلامی نقطہ نظر کو اوجھل...

Reconciliation Process in Afghanistan and Pakistan as Cardinal Player

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