Preferred Language
Articles
/
alkej-126
An Experimental Study on the Effect of Shape and Location of Vortex Generators Ahead of a Heat Exchanger
...Show More Authors

An experimental study is carried out on the effect of vortex generators (Circular and square) on the flow and heat transfer at variable locations at (X = 0.5, 1.5, 2.5 cm) ahead of a heat exchanger with Reynolds number ranging from 62000< Re < 125000 and heat flux from 3000 ≤ q ≤ 8000 W/m2 .

In the experimental investigation, an apparatus is set up to measure the velocity and temperatures around the heat exchanger.                     

The results show that there is an effect for using vortex generators on heat transfer. Also, heat transfer depends on the shape and location. The circular is found to be the best shape for enhancing heat transfer at location [Xm=0.5 cm] distance before heat exchanger is the best location for enhancing heat transfer. The square is the best shape for enhancing heat transfer at location [Xm=2.5 cm] distance before heat exchanger is the best location for enhancing heat transfer.

The results of flow over heat exchanger with vortex generators are compared with the flow over heat exchanger without vortex generators. Heat transfer around heat exchanger is enhanced (56%, 50%, 36%) at location            (X=0.5, 1.5, 2.5cm) respectively by using circular vortex generators without turbulator and heat transfer around heat exchanger is enhanced (39%, 42%, 51%) at location (X=0.5, 1.5, 2.5cm) respectively by using square shape vortex generators without turbulator.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Feb 25 2024
Journal Name
Baghdad Science Journal
Optimizing Blockchain Consensus: Incorporating Trust Value in the Practical Byzantine Fault Tolerance Algorithm with Boneh-Lynn-Shacham Aggregate Signature
...Show More Authors

The consensus algorithm is the core mechanism of blockchain and is used to ensure data consistency among blockchain nodes. The PBFT consensus algorithm is widely used in alliance chains because it is resistant to Byzantine errors. However, the present PBFT (Practical Byzantine Fault Tolerance) still has issues with master node selection that is random and complicated communication. The IBFT consensus technique, which is enhanced, is proposed in this study and is based on node trust value and BLS (Boneh-Lynn-Shacham) aggregate signature. In IBFT, multi-level indicators are used to calculate the trust value of each node, and some nodes are selected to take part in network consensus as a result of this calculation. The master node is chosen

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Thu Dec 01 2016
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
NEW HOST PLANTS RECORD FOR THE BROWN SOFT SCALE COCCUS HESPERIDUM LINNAEUS, 1758 (HEMIPTERA: COCCIDAE) IN BAGHDAD PROVINCE, IRAQ
...Show More Authors

    An investigation was provided in this work for the host range of brown soft scale Coccus hesperidum Linnaeus in Baghdad Province.  Five plant species were found infected by this insect, three of these species, Citrusaurantium L. (Rutaceae); Nerium oleander L. (Apocynaceae); Ficuscarica L. (Moraceae) reported earlier, and the remaining two, Dahlia pinnata Cav. (Asteraceae) and Myrtuscommunis L. (Myrtaceae) are recordedhere for the first time as host plants for this pest.

View Publication Preview PDF
Publication Date
Mon Jan 01 2024
Journal Name
Results In Nonlinear Analysis
Numerical solutions for the time fractional Black-Scholes model governing European option by using double integral transform decomposition method
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Fri Sep 17 2021
Journal Name
Review Of International Geographical Education Online
Following the Parashot Strategy in Developing Reading Understanding Skills among Female Students in the1st Middle Grade in Reading Material
...Show More Authors

The research aimed to know the effect of the Parashot strategy in developing the reading comprehension skills of first-grade intermediate students in reading. The researchers put the following two null hypotheses: There is no statistically significant difference at the level (0.05) between the average scores of the experimental group students who study the subject Reading with the Parashot strategy in the pre and post-tests in developing reading comprehension skills as a whole. There is no statistically significant difference at the level (0.05) between the average scores of the experimental group students who study the reading material using the Parashot strategy and the average scores of the control group students who study the same subje

... Show More
Preview PDF
Scopus
Publication Date
Mon Mar 15 2021
Journal Name
Iraqi National Journal Of Nursing Specialties
Nurses' Knowledge and Skills regarding Oxygen Administration Methods at Pediatric Teaching Hospitals in Mosul City
...Show More Authors

Objective: To assess knowledge and skills level regarding oxygen administration methods at p
ediatric teaching hospitals in Mosul City.
Methodology: A descriptive study was applied at pediatric teaching hospitals (Al-Kansaa, and Ibn Al-Atheer) in Mosul City from 8 of October / 2018 till 29 of May / 2019. The selection of the sample was non- probability (Purposive). This sample involved of (52) nurses. The questionnaire was constructed which consists of three parts and provided for nurses. The questionnaire validity was carried out through a panel of experts. To evaluate statistically the reliability of instruments, the pilot study was applied through period from 20– till –31 of January / 2019. Non-randomly (6) nurses from Ibn S

... Show More
View Publication Preview PDF
Publication Date
Sat Mar 30 2002
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Potential and Current Distribution in Flow Through Porous Electrochemical Reactor Working under Limiting Current Conditions
...Show More Authors

View Publication Preview PDF
Publication Date
Tue Jul 30 2024
Journal Name
Iraqi Journal Of Science
Frame-Based Change Detection Using Histogram and Threshold to Separate Moving Objects from Dynamic Background
...Show More Authors

      Detecting and subtracting the Motion objects from backgrounds is one of the most important areas. The development of cameras and their widespread use in most areas of security, surveillance, and others made face this problem. The difficulty of this area is unstable in the classification of the pixels (foreground or background). This paper proposed a suggested background subtraction algorithm based on the histogram. The classification threshold is adaptively calculated according to many tests. The performance of the proposed algorithms was compared with state-of-the-art methods in complex dynamic scenes.

View Publication Preview PDF
Scopus Crossref
Publication Date
Mon Mar 23 2020
Journal Name
Journal Of Engineering
Diagnosing Water Problem for Asmari Reservoir in Abu Ghirab Oilfield Using Analytical and Numerical Approaches
...Show More Authors

Asmari is the main productive reservoir in Abu Ghirab oilfield in the south-east part of Iraq. It has history production extends from 1976 up to now with several close periods. Recently, the reservoir suffers some problems in production, which are abstracted as water production rising with oil production declining in most wells. The water problem type of the field and wells is identified by using Chan's diagnostic plots (water oil ratio (WOR) and derivative water oil ratio (WOR') against time). The analytical results show that water problem is caused by the channeling due to high permeability zones, high water saturation zones, and faults or fracturing. The numerical approach is also used to study the water movement insi

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Mon Sep 02 2024
Journal Name
مجلة جامعة الانبار للعلوم القانونية والسياسية
Sustainable security strategies to confront violent extremism in Iraq after 2017 and their future prospects
...Show More Authors

As contemporary security requires the formulation of a comprehensive strategy based on multidimensional sub-strategies (economic, developmental, social, cybersecurity, military,and diplomatic dimensions to achieve so-called sustainable security and address the unconventional challenges that worsened with the turn of the twenty-first century and concerned with violent extremism, often leading to terrorism, Iraq, despite the reversal of the terrorist group ISIS in 2017, seems urgently needed to formulate effective strategies to counter violent extremism, Violent extremism has multiple internal and external reasons. These causes have increased due to local, regional, and international causes. Violent extremist factors began with the outbreak o

... Show More
View Publication
Publication Date
Mon Feb 01 2021
Journal Name
Iop Conference Series: Materials Science And Engineering
Pre-dissolved Inorganic Carbon (DIC) for cultivation Chlorella sorokiniana MH923013, Coelastrella MH923011 and Coelastrella MH923012
...Show More Authors
Abstract<p>A step to net-zero of carbon dioxide losses in the microalgae cultivation process was targeted in the current study. This research was carried out by using pre-dissolved inorganic carbon (DIC) as a source of carbon with two doses of twenty-five and fifty millilitres. <italic>C. sorokiniana</italic> MH923013, <italic>Coelastrella</italic> MH923011 and <italic>Coelastrella</italic> MH923012 strains were used in the present investigation. The experimental data emphasized the direct influence of carbonic solution on microalgal growth according to the fast adaption of algal cells and higher productivity compared to control and dilution cultures. It was observe</p> ... Show More
View Publication
Crossref (1)
Crossref