research centers


Search results: Found 3

Listing 1 - 3 of 3
Sort by

Article
NUMERICAL INVESTIGATION OF FLUID FLOW IN CAPILLARY TUBES

Author: Amir Hussein Ali
Journal: Journal of Basrah Researches (Sciences) مجلة ابحاث البصرة ( العلميات) ISSN: 18172695 Year: 2019 Volume: 45 Issue: 2A Pages: 33-43
Publisher: Basrah University جامعة البصرة

Loading...
Loading...
Abstract

This study was interested with fluid flow through narrow tubes. Finite volume method has been used as a numerical technique by the aid of computer to achieve the study. Cylindrical narrow tubes, represented as case A and case B have been used. Case A was a tube of radius (2 cm) and length (20 cm) while case B which has been used to investigate the effect of narrow tube on fluid flow was a tube of radius (2 mm) and length (20 mm). The initial conditions and boundary conditions for both cases were similar. Due to its widespread applications, air has been used as fluid material for the both cases. No slip condition at the wall has been used and viscous fluid flow was considered for both cases. Different parameters have been investigated for the two cases and have been compared to each other such as velocity magnitude, dynamic pressure, static pressure and wall shear stress. Case A has Reynold's number (Re) higher than case B. The velocity profiles of fully developed flow were compared with the parabolic velocity profile. Clear difference between the two cases A and B has been shown because of the narrowness of case B. The maximum velocity was at the tube centerline and zero at the tubes wall because of no slip condition was applied. Due to the differences in the diameters of the two cases, the results showed apparent differences between the two cases for velocity magnitude, dynamic pressure, static pressure and wall shear stress as well. The results of this study could be important for applications which include air flow in narrow tubes.


Article
Numerical Study on Hydrothermal Performance Factor Using Jet impingement and Nanofluid

Authors: Ibrahim K. Alabdaly a --- , M. A. Ahmed b*
Journal: Anbar Journal of Engineering Sciences مجلة الأنبار للعلوم الهندسية ISSN: 19979428 Year: 2019 Volume: 7 Issue: 4 Pages: 308-315
Publisher: University of Anbar جامعة الانبار

Loading...
Loading...
Abstract

In this study, thermal-hydraulic performance of a confined slot jet impingement with Al2O3-water nanofluid has been numerically investigated over Reynolds number ranges of 100-1000. Two triangular ribs are mounted at a heated target wall; one rib located on the right side of the stagnation point and another one located on left side of the stagnation point. The governing momentum, continuity and energy equations in the body-fitted coordinates terms are solved using the finite volume method and determined iteratively based on SIMPLE algorithm. In this study, effects of Reynolds number, rib height and rib location on the thermal and flow characteristics have been displayed and discussed. Numerical results show an increase in the average Nusselt number and pressure drop when Reynolds number and rib height increases. In addition, the pressure drop and average Nusselt number increases with decrease the space between the stagnation point and rib. The maximum enhancement of the average Nusselt number is up to 39 % at Reynolds number of 1000, the rib height of 0.3, rib location of 2 and nanoparticles volume fraction of 4%. The best thermal-hydraulic performance of the impinging jet can be obtained when the rib height of 0.2 and rib location of 2 from the stagnation point with 4% nanoparticles volume fraction.


Article
Numerical Investigation of Heat Transfer Enhancement of Double Pipe Heat Exchanger Using Metal Foam Fins
الفحص العددي لتحسين انتقال الحرارة لمبادل حراري مزدوج الانبوب باستخدام زعانف من رغوة معدنية

Authors: Jenan Abdulhasan Hamzah جنان عبد الحسن حمزة --- Mohammed A. Nima محمد عبد الرؤوف نعمة
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2019 Volume: 25 Issue: 6 Pages: 1-18
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

The influence of adding metal foam fins on the heat transfer characteristics of an air to water double pipe heat exchanger is numerically investigated. The hot fluid is water which flows in the inner cylinder whereas the cold fluid is air which circulates in the annular gap in parallel flow with water. Ten fins of metal foam (Porosity = 0.93), are added in the gap between the two cylinder, and distributed periodically with the axial distance. Finite volume method is used to solve the governing equations in porous and non-porous regions. The numerical investigations cover three values for Reynolds number (1000 ,1500, 2000), and Darcy number (1 x10-1, 1 x10-2, 1x10-3). The comparison between the two case with and without insertion the metal foam fins are examined in this study. Results show that the temperature of the inner pipe wall is affected by the Reynolds number, water inlet temperature, Darcy number variation. The resulting values and the behavior of the local and average coefficient of heat transfer are presented. The improvement in the mean coefficient of heat transfer (hm) is found to be 129 % with the using of the metal foam fins.

لقد تم نظريا دراسة تأثير إضافة زعانف من رغوة معدنية في مبادل حراري مزدوج الانبوب على خصائص انتقال الحرارة داخل هذا المبادل مع استخدام الهواء والماء كمائع مشغل. حيث ان المائع الساخن والذي يجري في الأسطوانة الداخلية هو الماء بينما الهواء هو المائع البارد والذي يجري في الفتحة الحلقية بين الاسطوانتين في جريان متوازي مع جريان الماء. تم إضافة عشرة زعانف من الرغوة المعدنية في الفتحة الحلقية بين الاسطوانتين، وتم توزيعها بشكل دوري مع محور الانبوبين. تم استخدام طريقة الحجم المحكوم لحل المعادلات الحاكمة في منطقة وجود وعدم وجود الوسط المسامي. شملت الدراسة النظرية قيم رقم رينولدز (1000, 2000,1500) وقيم رقم دارسي (1×10-1, 1×10-2, 1×10-3). أظهرت النتائج ان درجة حرارة سطح الأسطوانة الداخلية يتأثر بتغيير درجة حرارة دخول الماء للانبوب وكذلك بتغيير كل من رقم رينولدز وتغيير رقم دارسي مما يؤثر على عملية التبادل الحراري بين هذا السطح والمائع البارد (الهواء). نتائج تغير متوسط معامل أنتقال الحرارة في هذه الدراسة قد تم أظهارها وتحليلها. ووجد ان التحسين في متوسط معامل انتقال الحرارة (hm) كان (129%) مع استخدام زعانف الرغوة المعدنية.

Listing 1 - 3 of 3
Sort by
Narrow your search

Resource type

article (3)


Language

English (3)


Year
From To Submit

2019 (3)