Preferred Language
Articles
/
alkej-347
Experimental and Numerical Research on Flow-Induced Vibration in Valves
...Show More Authors

Abstract  

All central air conditioning systems contain piping system with various components, sizes, material, and layouts. If such systems in operating mode, the flow in piping system and its component such as valves can produce severe vibration due to some flow phenomenon’s. In this research, experimental measurements and numerical simulation are used to study the flow-induced vibration in valves. Computational fluid dynamics (CFD) concepts are included with one-way and two-way fluid-structure interaction concepts by using finite element software Package (ANSYS 14.57). Detection analysis is performed on flow characteristics under operation conditions and relations with structural vibration. Most of real geometrical, operational, and boundary conditions are simulated to obtain best similarity with real operation conditions. Comparisons performed between experimental data and numerical results (one-way and two-way simulation) to verify the results. The main conclusion was drawn from the study that the dominant source of vibration for valve is the water pulsation in addition to amount of water hammering. In addition, the main source of water pulsation in globe valve is the vortex shedding and pressure difference between upstream and downstream of valve. The vibration amplitude was increased with increasing flow rate until to be maximum when the flow rate around 30% and then decreased until flow rate reaches to around 85% and then trends to be constant.

Keywords: Flow-induced vibration, vortex shedding, pressure pulsation, valve, finite element, ANSYS, fast Fourier transform (FFT).

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Sep 01 2009
Journal Name
Al-khwarizmi Engineering Journal
Characterization of Metal Dispersion of Some Naphtha Reforming Catalysts by Methylcyclohexane Dehydrogenation Reaction
...Show More Authors

The dispersion of supported Pt and Pt–Ir reforming catalysts have been studied, after treatment with oxidative and reducing atmosphere. Methylcyclohexane dehydrogenation reaction in the absence of hydrogen was used as a test reaction. An attempt was made to relate the behavior of the catalysts upon subject to reaction, to the dispersion of the same type of catalysts upon treatment with similar atmosphere and temperatures which appeared in literature. The total conversion of reaction can be explained by a change in metal dispersion. Thus, methylcyclohexane dehydrogenation reaction appears to be a really “structure sensitive” reaction.

      The toluene yield increases as the oxidation temperature i

... Show More
View Publication Preview PDF
Publication Date
Tue Mar 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
Analyzing indicators of the results of applying forecasting methods for production plans (A case study at the Diyala State Company for Electrical Industries)
...Show More Authors

Economic organizations operate in a dynamic environment, which necessitates the use of quantitative techniques to make their decisions. Here, the role of forecasting production plans emerges. So, this study aims to the analysis of the results of applying forecasting methods to production plans for the past years, in the Diyala State Company for Electrical Industries.

The Diyala State Company for Electrical Industries was chosen as a field of research for its role in providing distinguished products as well as the development and growth of its products and quality, and because it produces many products, and the study period was limited to ten years, from 2010 to 2019. This study used the descriptive approa

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Dec 31 2021
Journal Name
Iraqi Journal Of Laser
Hong-Ou-Mandel Dip Measurements of Two Independent Weak Coherent Pulses for Free Space Quantum Key Distribution Systems
...Show More Authors

Preparation of identical independent photons is the core of many quantum applications such as entanglement swapping and entangling process. In this work, Hong-Ou-Mandel experiment was performed to evaluate the degree of indistinguishability between independent photons generated from two independent weak coherent sources working at 640 nm. The visibility was 46%, close to the theoretical limit of 50%. The implemented setup can be adopted in quantum key distribution experiments carried out with free space as the channel link, as all the devices and components used are operative in the visible range of the electromagnetic spectrum.

View Publication Preview PDF
Publication Date
Sun Dec 02 2018
Journal Name
Arab Science Heritage Journal
عبدالحميد الثاني والإستيطان الصهيوني في الولايات العربية من مشرق الوطن العربي مناطق الأختيار للإستيطان فلسطين والعراق
...Show More Authors

ترك السلطان عبدالحميد الثاني بصماتهُ على أخاديد الزمان وعلى خارطة المشرق العربي الخاضع للسيطرة العثمانية أنذاك ، لكونهُ أهم شخصية أسلامية غير عربية واجهت الخطر الصهيوني ومحاولاتهم الإستيطانية في مشرق الوطن العربي ، على الرغم من صعوبة الظروف التي كانت تمر بها الدولة العثمانية داخليا ً وخارجيا ً، بما فيها من أطماع اقتسامها بين الاوربين ولذا سموها بالرجل المريض .

View Publication Preview PDF
Publication Date
Thu Apr 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Using Project Management Maturity Model to Evaluate Construction Sector -Organizations. Case Study at the Department of buildings - Karkh first
...Show More Authors

The education sector suffers from many problems, including the scarcity of schools that can absorb the increasing number of students in light of the increasing population growth rate, as some regions suffer from a lack of opening of new schools or the expansion of existing schools to increase their capacity so that attention is required. The research sought to identify the level of maturity of project management at the research site (Building Department in Al-Karkh I/ Ministry of Education) Being responsible for educational projects and their implementation and to know that, the ten areas of the knowledge guide to project management PMBOK have been adopted according to the PM3 model (one of the models of maturity

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Jun 18 2022
Journal Name
Al-academy
دراسة مقارنة بين التعبير اللفظي والتعبير غير اللفظي في إخراج الدراما التلفزيونية المترجمة – جاك بريفير (أنموذجاً).
...Show More Authors
يهدف البحث الى اشاعة الدراسة المقارنة للنص المترجم الى اللغة العربية لتلافي الفوارق بين النص الأصلي (الأجنبي ) والنص المترجم (العربي ) من حيث المعاني والرموز والمعالجات الفكرية ... الخ .والتأكيد على استعمال التقنيات التربوية (السمعية والبصرية ) في الترجمة الانسانية (المتخصصة ) والاستعانة بالترجمة الآلية لتجنّب متاعب الترجمة والفهم الخاطىء او المنقوص ...للوصول الى فهم واسع بتدريس مادة الاخراج التلف
... Show More
View Publication Preview PDF
Publication Date
Mon Jan 01 2018
Journal Name
وقائع المؤتمر الدولي 7 للغة العربية / دبي
تقويم اداء اساتذة اللغة العربية العامة في كلية الادارة والاقتصاد جامعة بغداد من وجهة نظر طلبتهم
...Show More Authors

Publication Date
Sun Oct 01 2017
Journal Name
International Journal Of Computer Science And Information Security (ijcsis)
Finite State Automata Generator for DNA Motif Template as Preparation Step for Motif Mining
...Show More Authors

There are many tools and S/W systems to generate finite state automata, FSA, due to its importance in modeling and simulation and its wide variety of applications. However, no appropriate tool that can generate finite state automata, FSA, for DNA motif template due to the huge size of the motif template. In addition to the optional paths in the motif structure which are represented by the gap. These reasons lead to the unavailability of the specifications of the automata to be generated. This absence of specifications makes the generating process very difficult. This paper presents a novel algorithm to construct FSAs for DNA motif templates. This research is the first research presents the problem of generating FSAs for DNA motif temp

... Show More
Preview PDF
Publication Date
Tue Sep 01 2020
Journal Name
Journal Of Engineering
Buckling Behavior of Aluminum Alloy Thin-Walled Beam with Holes under Compression Loading
...Show More Authors

Thin-walled members are increasingly used in structural applications, especially in light structures like in constructions and aircraft structures because of their high strength-to-weight ratio. Perforations are often made on these structures for reducing weight and to facilitate the services and maintenance works like in aircraft wing ribs. This type of structures suffers from buckling phenomena due to its dimensions, and this suffering increases with the presence of holes in it. This study investigated experimentally and numerically the buckling behavior of aluminum alloy 6061-O thin-walled lipped channel beam with specific holes subjected to compression load. A nonlinear finite elements analysis was used to obtain the

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Wed Jul 01 2020
Journal Name
Ieee Transactions On Industrial Electronics
Finite-Time Continuous Terminal Sliding Mode Control of Servo Motor Systems
...Show More Authors

In this article, a continuous terminal sliding mode control algorithm is proposed for servo motor systems. A novel full-order terminal sliding mode surface is proposed based on the bilimit homogeneous property, such that the sliding motion is finite-time stable independent of the system’s initial condition. A new continuous terminal sliding mode control algorithm is proposed to guarantee that the system states reach the sliding surface in finitetime. Not only the robustness is guaranteed by the proposed controller but also the continuity makes the control algorithm more suitable for the servo mechanical systems. Finally, a numerical example is presented to depict the advantages of the proposed control algorithm. An application in the rota

... Show More
View Publication
Scopus (252)
Crossref (221)
Scopus Clarivate Crossref