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Article
A new Measuring Criterion of the Performance of the Electromagnetic Flow meter

Authors: Muneer A. Ismael --- Riadh H. AI-Rabeh
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2010 Volume: 10 Issue: 1 Pages: 133-144
Publisher: Basrah University جامعة البصرة

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Abstract

The weight function prescribing the sensitivity of the electromagnetic flowmeter (EMF) to the changes in the velocity profiles must be as much as possible uniformly distributed through the measuring volume. The most common used criterion of the weight function distribution is a statistical quantity (c criterion) which deals with only the axial component of the weight vector. In the present work an attempt to introduce more revealing and accurate criterion to the EMF performance was studied. The curl of the weight function vector over the measuring volume has been considered and formulated (and termed as in such a mathematical expression that takes into account the contributions of the three components of the weight vector regardless of thc geometry of cross-sectional area of the flow. In addition, a numerical solution of a previously defined criterion (sj is presented here for a first time in order to compare the validity of the newly introduced criterion. The results showed that the present new criterion e is closely harmonious with the previously defined criteria s and 8 in the conventional flow cases. The results and the configuration of the formula of the present criterion which is independent of the flow cross- sectional are led us to conclude that is more reliable and applicable than other existing criteria

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Article
Numerical and Experimental Study of the Performance of Electromagnetic Flowmeter in Annular Flow

Authors: Ihsaan Nadhum Jawaad --- Muneer A. Ismael
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2014 Volume: 14 Issue: 2 Pages: 122-136
Publisher: Basrah University جامعة البصرة

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Abstract

The present numerical and experimental work investigates the performance of electromagnetic flowmeter (EMF) for measuring the flow rate of annular flow. Adaptive finite difference technique is used for the numerical calculations and the experimental work is done by making some modification on an existing electromagnetic flowmeter and its testing rig. The performance of the modified EMF is evaluated using two criteria namely, the flowmeter sensitivity S and the conventional weight function non uniformity ε. These two criteria were checked against two parameters; thickness of flowing water (δ) and the electrodes angular position (θe). Experimentally, three different water thickness (δ/Ro = 0.216, 0.373, 0.218) and three electrode position (θe=0o, 11.25o, 45o) were studied. The theoretical and experimental results have showed that these devices work properly in the annular flow case, where the most suitable electrode position in the annular flow was found to be in the conventional position (θe =0o).


Article
NATURAL CONVECTION IN A WAVY POROUS ENCLOSURE HEATED BY AN INTERNAL CIRCULAR CYLINDER
الحمل الحر داخل وعاء مسامي متموج مسخن من الداخل بأسطوانة دائرية

Author: Dr. Muneer A Ismael د.منير عبد الجليل إسماعيل
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2011 Volume: 4 Issue: 3 Pages: 310-326
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

Natural convection fluid flow and heat transfer of fluid-saturated porous media heated by an internal circular cylinder inside a wavy enclosure is investigated numerically. The 2D enclosure is composed of two isothermal vertical wavy walls and two adiabatic horizontal flat walls. Darcy assumption and Boussinesq approximation were relied on in this steady, incompressible study. The governing equations were solved using Galerkin finite element method implemented in FlexPDE software package. The performance of enclosure was evaluated by three non-dimensional parameters namely, the Darcy-modified Rayleigh number Ram (100-1000), the waviness ratio λ (0-0.35), and the position of the inner heated cylinder ξ (0.45-1.05). The results were presented by visualization of the streamline and isothermal contours and by the local and average Nusselt numbers. It was found that the lower the position of the inner cylinder (ξ=0.45) is the largest the values of Nusselt number while the influence of the wall waviness ratio is found to be very small.

تم في هذا البحث دراسة عددية لجريان و انتقال الحرارة بالحمل الحر لمائع مشبع في وسط مسامي داخل وعاء متموج مسخن من الداخل بواسطة اسطوانة دائرية. يتكون هذا الوعاء المتموج من جدارين عموديين متموجين مثبتين عند درجة حرارة ثابتة و جدارين افقيين مستويين معزولين حراريا. بُنيت التحليلات على فرضية دارسي (Darcy assumption) وتقريبات باوسنك (Boussinesq approximation). تم حل المعادلات الحاكمة بأستخدام طريقة العناصر المحددة المزودة في حقيبة برمجية (FlexPDE). أُستخدمت ثلاثة معايير لا بعدية من اجل دراسة الأداء الحراري للوعاء المتموج هي: رقم دارسي- رايلي المعدل Ram (100-1000), نسبة التموج λ(0-0.35) و موقع الأسطوانة الداخلية المسخنة ξ(0.45-1.05). لقد مُثلت النتائج بواسطة معاينة خطوط الجريان (streamlines) و خطوط التحارر (isotherms) وكذلك عن طريق رقم نسلت الموقعي و المتوسط. لقد بَينت النتائج بأن الموقع الأدنى للأسطوانة الداخلية (ξ=0.45) يعطي أكبر قيم لرقم نسلت في حين وجد ان تأثير نسبة التموج قليل جدا.


Article
Study of Natural Convection in a Horizontal Square Enclosure with 4-Inner Heated Rods
دراسة نظرية للحمل الحر داخل فجوة افقية مسخنة بأربعة قضبان اسطوانية

Authors: Muneer A. Ismael --- Falah A. Abood --- Sana J. Yaseen
Journal: University of Thi-Qar Journal for Engineering Sciences مجلة جامعة ذي قار للعلوم الهندسية ISSN: 26645564/26645572 Year: 2011 Volume: 2 Issue: 3 Pages: 19-34
Publisher: Thi-Qar University جامعة ذي قار

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Abstract

Laminar, natural convection heat transfer of air filling horizontal space between isothermal (cold) square enclosure and four isothermal (hot) cylindrical rods has been theoretically studied. Finite element method has been used to solve the conservation of governing equations by using software package (FlexPDE).Parametric study has been conducted for the range of Rayliegh number10,Aspect ratio 0.11AR0.28. Results are presented in the form of streamlines, isotherms contours and Nusselt numbers. Results showed that the overall heat transfer increases with increasing of both Ra and AR. The values of mean Nusselt numbers are compared with datareported in Ref.[6] and [15] , and good agreement has been achieved.3 Ra10 5


Article
ADAPTIVE MEŠH NUMERICAL SOLUTION OF THE ELECTROMAGNETIC FLOWMETER FOR PARTIALLY- FILLED PIPES

Authors: Mr. Muneer A. Ismael --- Qais A. Rashak --- Saleh Esmael Najem
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2007 Volume: 7 Issue: 1 Pages: 33-43
Publisher: Basrah University جامعة البصرة

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Abstract

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Article
Effect of Magnetic Field Distribution on the Performance of the Electromagnetic Flow meter ia Partially- Filled Pipes

Authors: Muneer A. Ismael --- Qais A. Rashack --- S.E. Najem
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2009 Volume: 9 Issue: 1 Pages: 25-33
Publisher: Basrah University جامعة البصرة

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Abstract

Electromagnetic flowmeters have proven their merit in measuring the flow rate of conducting liquids in fully-filled pipes. In contrast with the most of the published works about the electromagnetic flowmeter. the attentions were focused in this work into the use of these devices in partially-filled pipes. In this application these devices suffer from the problem of different outputs with different liquid level for the same flow rate. We studied whether the process of changing the distribution of the magnetic field through the measuring section improves the flowmeter performance against this drawback or not. An adaptive numerical mesh was used in predicting the flow induced signal and its response to the liquid level. The induced signal was assumed to be picked up by a pair of point electrodes tested for different angular positions. The results showed that the performance of the electromagnetic flowmeter in partially- filled pipes could be appreciably improved by making the magnetic field progressively decreases from top to the bottom of the flowmeter. When the lower magnet coil is excited by a current one- half lower than the upper coil together with two point electrodes placed at 22° below the flowmeter horizontal centerline, the fiowrneter performance offer more stable sensitivity.

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Article
Natural Convection Heat Transfer in Arc Shape Wall Porous Cavity Filled with Nano-Fluid

Authors: Muneer A. Ismael --- Huda A. AL-Mayahi --- Ihsan N. Jawad
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2014 Volume: 14 Issue: 2 Pages: 137-148
Publisher: Basrah University جامعة البصرة

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Abstract

Natural convection heat transfer in porous cavity with arc shape wall filled with nanofluid is studied numerically. The right arc shape wall of the cavity is heated at constant temperature (Th) while the left wall is kept cold at constant temperature (Tc), and the other horizontal walls are thermally insulated. The governing equations of the heat transfer and nanofluid flow are solved Flex PDE software. A temperature independent nanofluids properties models are adopted. The investigated parameters are the nanoparticles volume fraction Ø= (0-0.2), Rayleigh number Ra (10-1000) and arc center Ce (1-∞). The results are presented by contour of streamlines, isotherms and the average Nusselt number. The results have showed that the average Nusselt number decreases with increasing Ce and increases with increasing Ra and Ø.


Article
MEASUREMENT OF LIQUID LEVEL IN PARTIALLY-FILLED PIPES USING A NOISE OF ELECTROMAGNETIC FLOWMETER

Authors: Muneer A. Ismael --- Rafil M. Laftah --- Mustafa N. Falih
Journal: Al-Qadisiyah Journal for Engineering Sciences مجلة القادسية للعلوم الهندسية ISSN: 19984456 Year: 2017 Volume: 10 Issue: 4 Pages: 550-564
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

This paper investigates the measurement of liquid level in partially filled pipes utilizing an electrical noise signal (transformer signal) generated in electromagnetic flowmeter namely, transformer signal. The study was conducted by experiments and the collected data were analyzed statistically using Artificial Neural Network (ANN). The experimental study was achieved by building a laboratory rig containing the main parts of electromagnetic flowmeter. The main parameters which have been studied were the liquid level, magnetic field strength ( = 0.00809T, 0.03308T, 0.05301T), liquid temperature ( = 11º to 21.5º ) and liquid electrical conductivity ( = 0.11225, 3.08, 210, mS/cm). The collected data were analyzed using the back propagation neural network technique included in Matlab software 2009. The results show that the transformer signal is greatly influenced by variations of the liquid level inside partially filled electromagnetic flowmeter. The electrode position of ( = 160º) has had the strongest response to liquid level. The electrode position effect on the transformer signal is the greatest compared with that of the liquid temperature and the strength of the magnetic field. Generally, the transformer signal was found to be an increasing function with decreasing of liquid level.


Article
Steady Laminar Natural Convection Heat Transfer inside Air-Filled Horizontal Triangular Enclosure Containing Three Cylindrical Rods

Authors: Muneer A. Ismael منير عبد الجليل اسماعيل --- Falah Assi Abood فلاح عاصي عبود
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2011 Volume: 11 Issue: 1 Pages: 57-71
Publisher: Basrah University جامعة البصرة

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Abstract

The natural convection heat transfer from horizontal isothermal three cylindrical rods inside equilateral triangular enclosure has been studied numerically. The enclosure is filled with air, and the heated rods are located at equal distances (E) from triangle center. A finite element software package (FLEXPDE) is used in the present study to solve the set of non-linear equations governing the process. Solutions are obtained for aspect ratio D/H=1/6 and range of distance E=0.2-0.6 and Rayleigh (Ra) number changes from 103 to 106. The effect of Ra and E were examined. Results are presented by streamlines, isotherms and Nusselt number and it indicates that the Nusselt number is significantly increase with increasing both Ra and E. A comparison of the Nusselt number was made with that obtained by [7], and showed substantial improvement to about 65% in some cases


Article
Conjugate Heat transfer in a Differentially Heated Porous Cavity Filled with Nanofluid
انتقال الحرارة المقترن خلال فجوة مسامية مشبعة بمائع نانوي و مسخنة تباينيا

Authors: Muneer A. Ismael منير عبد الجليل اسماعيل --- Ahmed Abdulkareem Mahdi احمد عبدالكريم مهدي
Journal: Basrah Journal for Engineering Science مجلة البصرة للعلوم الهندسية ISSN: Print: 18146120; Online: 23118385 Year: 2013 Volume: 13 Issue: 1 Pages: 123-139
Publisher: Basrah University جامعة البصرة

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Abstract

The conjugate natural convection-conduction heat transfer in a domain composed of nanofluids filled porous cavity heated by a vertical solid wall is studied under steady-state conditions. The vertical left wall of the solid is kept isothermal at hot temperature Th. The vertical right wall of the solid is in contact with the nanofluid saturated porous medium contained in the cavity. The right vertical wall of the cavity is kept isothermally at the lower temperature Tc. The upper and lower horizontal walls are kept adiabatic. The governing equations of the heat transfer in the solid wall and heat and nanofluid flow, based on the Darcy model, in the nanofluid-saturated porous medium together with the derived relation of the interface temperature are solved numerically using the over-successive relaxation finite-difference method. A temperature independent nanofluids properties model is adopted. The investigated parameters are the nanoparticles volume fraction (0-0.2), Rayleigh number Ra (10-1000), solid wall to base-fluid saturated porous medium thermal conductivity ratio kwf (0.1, 1, 10), and the solid wall thickness D (0.05-0.5). The results are presented in the conventional form; contours of streamlines and isotherms and the average Nusselt number. At a very low Rayleigh number Ra=10, an enhancement in heat transfer within the porous cavity with is observed. Otherwise, the heat transfer may be unchanged or deteriorated with depending on the wall thickness D and the conductivity ratio kwf.

تم في هذا البحث دراسة انتقال الحرارة المقترن (حمل-توصيل) خلال حيز مكون من فجوة مسامية مشبعة بمائع نانوي و مسخنة بجدار عمودي تحت ظرف الأستقرار. سطح الجدار العمودي الأيسر مثبت عند درجة حرارة ساخنة Th و سطحه الأيمن في حالة تلامس مع المائع النانوي المشبع داخل الفجوة المسامية. جدار الفجوة الأيمن مثبت عند درجة حرارة باردة Tc . جدارا الفجوة الأعلى و الأسفل معزولان حرارياً. تم حل المعادلات الحاكمة لأنتقال الحرارة خلال الجدار الأيمن و معادلات انتقال الحرارة و جريان المائع النانوي (الذي بني على أساس نموذج دارسي) خلال الفجوة وكذلك المعادلة المشتقة للسطح المشترك Interface بأستخدام طريقة الفروقات المحددة. خواص المائع النانوي اعتبرت ثابتة مع درجة الحرارة. المتغيرات التي تمت دراستها هي النسبة الحجمية للجسيمات النانوية , رقم رايليRa=(10-1000) , نسبة الموصلية الحرارية للجدار العمودي الى المائع الأساس kwf=(0.1, 1, 10) وسمك الجدار العمودي D=(0.05-0.5). تم تمثيل النتائج بالطريقة المعروفة, أي خطوط دالة الجريان و التحارر و متوسط رقم نسلت. بينت النتائج بأنه عند قيمة Ra=10 هنالك تحسن في عملية انتقال الحرارة داخل الفجوة المسامية بزيادة النسبة الحجمية للجسيمات النانوية. فيما عدا ذلك, فأن انتقال الحرارة قد لا يتغيراو يتناقص مع اعتمادا على سمك الجدار D و نسبة الموصلية الحرارية kwf

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