research centers


Search results: Found 3

Listing 1 - 3 of 3
Sort by

Article
Aerodynamic Characteristics of a Rectangular Wing Using Non-Linear Vortex Ring Method
خصائص الديناميكا الهوائية لجناح مستطيل باستخدام طريقة الدوامة الحلقية غير الخطية

Author: Anmar Hamid Ali انمارحامد علي
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2017 Volume: 23 Issue: 4 Pages: 125-141
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

The aerodynamic characteristics of general three-dimensional rectangular wings are considered using non-linear interaction between two-dimensional viscous-inviscid panel method and vortex ring method. The potential flow of a two-dimensional airfoil by the pioneering Hess & Smith method was used with viscous laminar, transition and turbulent boundary layer to solve flow about complex configuration of airfoils including stalling effect. Viterna method was used to extend the aerodynamic characteristics of the specified airfoil to high angles of attacks. A modified vortex ring method was used to find the circulation values along span wise direction of the wing and then interacted with sectional circulation obtained by Kutta-Joukowsky theorem of the airfoil. The method is simple and based mainly on iterative procedure to find the wings post stall aerodynamic results. Parametric investigation was considered to give the best performance and results for the rectangular wings. Wing of NACA 0012 cross sectional airfoil was studied and compared with published experimental data for different speeds and angle of attacks. Pressure, skin friction, lift, drag, and pitching moment coefficients are presented and compared good with experimental data. The present method shows simple, quick and accurate results for rectangular wings of different cross-section airfoils.

تمت دراسة الخصائص الايروديناميكية للاجنحة الثلاثية الابعاد المستطيلة الشكل باستخدام التاثير اللاخطي المتبادل بين طريقة الالواح لزج-غير لزج ثنائية البعد وطريقة الدوامة الحلقية .ان الجريان الكامن لجنيح ثنائي البعد بطريقة Hess و Smith البدائية قد استخدم مع الطبقة المتاخمة الطباقية ,الانتقالية والمضطربة لحل الجريان حول اشكال معقدة من الجنيحات متضمنا تاثير الانهواء فيها .طريقة فيترنا استخدمت لتمديد الخواص الايروديناميكية للجنيح الى زوايا هجوم عالية .طريقة الدوامة الحلقية المعدلة استخدمت لايجاد قيم التدوير على طول امتداد الجناح وايجاد تاثيرها مع التدورة المقطعي الماخوذة من نظرية Kutta-Joukowsky للجنيح. الطريقة بسيطة وتعتمد اساسا على عملية التاثير المتبادل لايجاد النتائج الايروديناميكية الاجنحة ما بعد الانهواء. تمت دراسة العوامل التي تعمل على اعطاء افضل اداء ونتائج للمسالة . الجناح ذو مقطع مطيار NACA 0012 تمت دراسته ومقارنته مع البيانات العملية المنشورة لمختلف السرع وزوايا الهجوم. معامل الضغط, الاحتكاك, الرفع, الممانعة, و عزم التارجح قد تم عرضها ومقارنتها جيدا مع البيانات العملية. ان الطريقة الحالية تظهر بساطة, سرعة ودقة النتائج للجناح المستطيل ولمختلف مقاطع الجنيحات.


Article
Evaluation of Risk Factors For Acute Periprosthetic Infection Post Total Knee Replacement Iraqi Patients

Authors: Mahmood Shihab --- Hazim A. Aljumily --- Belal Salman --- Anmar Hamid
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2016 Volume: 13 Issue: 2 Pages: 549-555
Publisher: Babylon University جامعة بابل

Loading...
Loading...
Abstract

Periprosthetic joint infection (PJI) is one of the most challenging complications after total joint arthroplasty,with an incidence of 1% to 4% after primary TKA. This complication poses challenges on many aspects, one ofwhich is the difficulty in reaching a diagnosis.Although variation exists, the majority of them rely on the results of joint aspiration or deep tissue culture;serologic tests, namely erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP); and theappearance of the joint during surgery (with regard to presence of purulence); presence or absenceof a sinus tract; and the result of histologic analysis of tissue obtained during surgery (frozen section).Taken together, these findings suggest incorporating synovial WBC and PMN% results into a set of diagnosticcriteria may improve the strength of those criteria for diagnosing PJI.The Objective is To evaluate the risk factors for peri-prosthetic infection post total knee replacement for Iraqipatients.This prospective study consists of 264 patients (51 males and 213 females) ages ranged from 49-75 years(mean 62 years) had been performed unilateral primary total knee replacement between January 2012 toSeptember 2013 in the Nursing Home Hospital arthroplasty Department, in Baghdad, that are divided into threegroups according to the primary pathology, Group I are 207 patients had primary osteoarthritis, GroupII are 42 patients had rheumatoid arthritis, and Group III are 15 post-traumatic arthritis.264 patients with 51 (19.3 %) males and 213 (80.6 %) females’ patients had primary OA 207 case (74.8%),Rheumatoid arthritis 42 case (15.9%) and posttraumatic 15 cases (5.6%). These patients were allocated into 3groups according to their primary pathology:In Group I, 182 patients (non-diabetic), 4 patients had deep infection, whereas 3 of 25 diabetic patients developeddeep infection. In Group II, 34 non diabetic patients, and 8 diabetic patients one and 2 patients had deep infectionrespectively. Group III, 12 non-diabetic and 3 diabetic patients had one patient each with documented deep woundinfection. As a total number of documented acute deep infections during 6 weeks of TKR is 12 cases (4.5%).We conclude that: Diabetic patients are more risk in early postoperative infection than non-diabetic patients.Rheumatoid arthritis adds more incidence of infection to diabetic patients in the TKR. posttraumatic arthritispatients considered as a risk for early postoperative deep infection.


Article
Testing and Commissioning of a Low-Speed Wind Tunnel (LSWT) Test Section
معايرة مقطع اختبار لنفق هوائي واطيء السرعة

Authors: Ihssan Y. Hussain أحسان يحيى حسين --- Anmar Hamid Ali أنمارحامد علي
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2014 Volume: 20 Issue: 11 Pages: 106-125
Publisher: Baghdad University جامعة بغداد

Loading...
Loading...
Abstract

The calibration of a low-speed wind tunnel (LSWT) test section had been made in the present work. The tunnel was designed and constructed at the Aerodynamics Lab. in the Mechanical Engineering Department/University of Baghdad. The test section design speed is 70 m/s. Frictional loses and uniformity of the flow inside the test section had been tested and calibrated based on the British standards for flow inside ducts and conduits. Pitot-static tube, boundary layer Pitot tube were the main instruments which were used in the present work to measure the flow characteristics with emphasize on the velocity uniformity and boundary layer growth along the walls of the test section. It is found that the maximum calibrated velocity for empty test section is 55 m/s. Three speeds are tested for uniformity and walls boundary layer at inlet and mid-section of test section. The results show that the flows are uniform at inlet and mid-section with turbulent flow from inlet to outlet.

في هذا العمل تمت معايرة مقطع اختبار لنفق هوائي واطيء السرعة. تم تصميم وتركيب النفق (في عمل سابق) في مختبر الهوائيات بقسم الهندسة الميكانيكية-جامعة بغداد. السرعة التصميمية لمقطع الاختبار هي 70 مثا. تم اختبار ومعايرة الخسائر الاحتكاكية والتجانس للجريان داخل مقطع الاختبار بالاعتماد على المواصفات البريطانية للجريان داخل الانابيب والانفاق. انبوب Pitot-static, وانبوب Pitot للطبقة المتاخمة استخدما كوسائل رئيسة في البحث الحالي لقياس خواص الجريان مع التشديد على تجانس السرعة وتنامي الطبقة المتاخمة لجدران مقطع الاختبار. تم معايرة السرعة القصوى لمقطع الاختبار وهو فرغ وقد كانت 55 مثا. ثلاث سرع تم اختبارها لقياس التجانس والطبقة المتاخمة للجدران عند الدخول والمقطع النصفي لمقطع الاختبار. النتائج اظهرت ان الجريان منتظم عند الدخول والمقطع النصفي بجريان مضطرب من المدخل حتى المخرج.

Listing 1 - 3 of 3
Sort by
Narrow your search

Resource type

article (3)


Language

English (3)


Year
From To Submit

2017 (1)

2016 (1)

2014 (1)