Preferred Language
Articles
/
joe-928
Numerical Study of Fluid Flow and Heat Transfer Characteristics in Solid and Perforated Finned Heat Sinks Utilizing a Piezoelectric Fan
...Show More Authors

Numerical study is adapted to combine between piezoelectric fan as a turbulent air flow generator and perforated finned heat sinks. A single piezoelectric fan with different tip amplitudes placed eccentrically at the duct entrance. The problem of solid and perforated finned heat sinks is solved and analyzed numerically by using Ansys 17.2 fluent, and solving three dimensional energy and Navier–Stokes equations that set with RNG based k−ε scalable wall function turbulent model. Finite volume algorithm is used to solve both phases of solid and fluid. Calculations are done for three values of piezoelectric fan amplitudes 25 mm, 30 mm, and 40 mm, respectively. Results of this numerical study are compared with previous both numerical and experimental studies and give a good agreement. Numerical solution is invoked to explain the behavior of air flow and temperature distribution for two types of circular axial and lateral perforations. For each type, all the results are compared with an identical solid finned heat sink. Perforations show a remarkable enhanced in the heat transfer characteristics. The results achieved enhancement in the heat transfer coefficient about 12% in axial perforation and 25% in the lateral perforation at the maximum fan amplitude.

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Heating and Melting Model Induced by Laser Beam in Solid Material
...Show More Authors

An analytical method and a two-dimensional finite element model for treating the problem of laser heating and melting has been applied to aluminum 2519T87and stainless steel 304. The time needed to melt and vaporize and the effects of laser power density on the melt depth for two metals are also obtained. In addition, the depth profile and time evolution of the temperature before melting and after melting are given, in which a discontinuity in the temperature gradient is obviously observed due to the latent heat of fusion and the increment in thermal conductivity in solid phase. The analytical results that induced by  laser irradiation is in good agreement with numerical results.

View Publication Preview PDF
Publication Date
Tue Mar 01 2016
Journal Name
Journal Of Engineering
Dynamic Stability Analysis and Critical Speed of Rotor supported by a Worn Fluid film Journal Bearings
...Show More Authors

In this paper, the effect of wear in the fluid film journal bearings on the dynamic stability of rotor bearing system has been studied depending on the development of new analytical equations for motion, instability threshold speed and steady state harmonic response for rotor with offset disc supported by worn journal bearings. Finite element method had been used for modeling the rotor bearing system. The analytical model is verified by comparing its results with that obtained numerically for a rotor supported on the short bearings. The analytical and numerical results showed good agreement with about 8.5% percentage error in the value of critical speed and about 3.5% percentage error in the value of harmonic response. T

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 01 2019
Journal Name
2019 First International Conference Of Computer And Applied Sciences (cas)
Influence of Peristaltic Flow And Brownian Motion Of Jeffery Nanofluid In A Tapered Asymmetric Channel
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Wed Mar 30 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Kinetics and Mass Transfer Study of Oleic Acid Esterification over Prepared Nanoporous HY zeolite
...Show More Authors

A mathematical model was proposed to study the microkinetics of esterification reaction of oleic acid with ethanol over prepared HY zeolite catalyst. The catalyst was prepared from Iraqi kaolin source and its properties were characterized by different techniques. The esterification was done under different temperature (40 to 70˚C) with 6:1 for molar ratio of ethanol to oleic acid and 5 % catalyst loading.    The microkinetics study was done over two period of time each period was examined individually to calculate the reaction rate constant and activation energy. The impact of the mass transfer resistance to the reactant was also investigated; two different studies have been accomplished to do this purpose.    The e

... Show More
View Publication
Crossref (10)
Crossref
Publication Date
Thu Jun 20 2024
Journal Name
Acta Facultatis Medicae Naissensis
Clinical properties and seminal fluid analysis of patients with primary infertility consulting the urology outpatient clinic for the first time: A cross-sectional study
...Show More Authors

Introduction/Aim. Seminal fluid analysis (SFA) plays a crucial role in helping infertility clinics diagnose the underlying reason of male infertility. The aim of the study was to investigate seminal fluid patterns of male partners of an infertile couple with apparently fertile female partners. Materials and methods. A cross-sectional study was conducted between January 2019 and December 2022. Patients were attending consultations for delayed conception for more than 12 months with apparently fertile female partner. Results. Four hundred fifty-three patients were included in the study. The distribution of patients according to age groups showed that 277 patients were young, aged 21 - 30 years (61%). Two hundred sixty-two (58%) patien

... Show More
View Publication Preview PDF
Scopus Clarivate Crossref
Publication Date
Mon Jan 29 2024
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
Role of Ultrasound in Antenatal Detection of Echogenic Amniotic Fluid and Pregnancy Outcome
...Show More Authors

Background: Ultrasound is a valuable tool for evaluating fetal problems throughout pregnancy. Amniotic fluid anomalies have been associated with unfavorable maternal, fetal, and obstetrical outcomes. Objective: To determine the effect of echogenic amniotic fluid during term pregnancy on the presence of meconium stain liquor and pregnancy outcome. Methods: A cross-sectional study was conducted on 1080 term pregnant women who visited Al-Elwiya Maternity Teaching Hospital from May 1st, 2021, to May 1st, 2023. Ultrasound was used to analyze echogenic amniotic fluid and turbid liquor. The liquor state was tested either after an artificial membrane rupture in the vaginal delivery trial or during a cesarean section. Results: Echogenic amni

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Fri Sep 15 2023
Journal Name
Journal Of Baghdad College Of Dentistry
The influence of lemongrass essential oil addition into heat cured acrylic resin against Candida albicans adhesion
...Show More Authors

Background: For decades, the use of naturally accessible materials in treating human disease has been widespread. The goal of this study was to determine the anti-fungal effectiveness /of the lemongrass essential oil (LGEO) versus Candida albicans (C. albicans) adhesion to polymethylmethacrylate (PMMA) materials. Material and methods: LGEO's anti-fungal activity was tested against C. albicans adhesion using the following concentration of LGEO in PMMA monomer (2.5 vol. %, 5 vol. % LGEO) selected from the pilot study as the best two effective concentrations. A total of 40 specimens were fabricated for the candida adherence test and were subdivided into four equal groups: negative control 0 vol. % addition, experimental with 2.5 vol. % and

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (3)
Scopus Crossref
Publication Date
Tue Mar 13 2018
Journal Name
Mustansiria Dental Journal
Dimensional stability of heat-activated acrylic resin at different time intervals by different flask cooling methods
...Show More Authors

This study was design to investigate the dimensional stability of heat-activated acrylic resin with different methods of flask cooling (15 minutes rapid cooling, one hour bench cooling, four hours delayed deflasking, and 24 hours delayed deflasking) at different time intervals (immediately, two days, seven days, 30 days) after deflasking. Heat-activated acrylic resin was used to prepare acrylic samples. Then, measurement of the distances where achieved between the centers of selected marks in the acrylic samples. They were measured at different time intervals for different methods of flask cooling. The results showed that the group samples of the four hours and 24 hours of delayed deflasking was insignificantly different from the control an

... Show More
Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Iop Conference Series: Earth And Environmental Science
Residual post fire strength of non-prismatic perforated beams
...Show More Authors
Abstract<p>The main aim of this study is to assess the performance and residual strength of post-fire non-prismatic reinforced concrete beams (NPRC) with and without openings. To do this, nine beams were cast and divided into three major groupings. These groups were classified based on the degrees of heating exposure temperature chosen (ambient, 400, and 700°C), with each group containing three non-prismatic beams (solid, 8 trapezoidal openings, and 8 circular openings). Experimentally, given the same beam geometry, increasing burning temperature caused degradation in NPRC beams, which was reflected in increased mid-span deflection throughout the fire exposure period and also residual deflectio</p> ... Show More
View Publication Preview PDF
Scopus (5)
Crossref (1)
Scopus Crossref
Publication Date
Mon Aug 01 2022
Journal Name
Bulletin Of Electrical Engineering And Informatics
Solid waste recycling and management cost optimization algorithm
...Show More Authors

Solid waste is a major issue in today's world. Which can be a contributing factor to pollution and the spread of vector-borne diseases. Because of its complicated nonlinear processes, this problem is difficult to model and optimize using traditional methods. In this study, a mathematical model was developed to optimize the cost of solid waste recycling and management. In the optimization phase, the salp swarm algorithm (SSA) is utilized to determine the level of discarded solid waste and reclaimed solid waste. An optimization technique SSA is a new method of finding the ideal solution for a mathematical relationship based on leaders and followers. It takes a lot of random solutions, as well as their outward or inward fluctuations, t

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (5)
Scopus Crossref