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Numerical Study of Fluid Flow and Heat Transfer Characteristics in Solid and Perforated Finned Heat Sinks Utilizing a Piezoelectric Fan
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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.

 

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Publication Date
Sun Jun 03 2012
Journal Name
Baghdad Science Journal
Study the spectroscopic characteristics of Rhodamine B Dye in Ethanol and Methanol mixture and Calculation the Quantum Efficiency
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The effect of ethanol and methanol solvent, and their mixture has been studied on the absorption and fluorescence spectra of laser dye Rhodamine B at concentration of (10-4) Molar at room temperature. The molar absorption coefficient has been determined for mixture which was (3.223) at wave number (18181.8 cm-1), Also the Quantum Efficiency of the two solvents (ethanol and methanol) and their mixture have been calculated ,which was for mixture spectrum (38.94%) and it was larger comparing with other and solvents. The characteristics of spectrum has been determined by calculating (??) of absorption spectrum for the solvents and its mixture at maximum wave number ( ) cm-1 depending on solvent polarity and the transitions between molecular ene

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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Heating and Melting Model Induced by Laser Beam in Solid Material
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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.

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Publication Date
Thu Jun 15 2023
Journal Name
Jornal Of Al-muthanna For Agricultural Sciences
Effect of different levels of Adrenocorticotropic hormone (ACTH) on physiological performance of broiler under heat stress conditions.
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This experiment was holdup in A-Faris poultry farms from 1st March to 11 of Aprile 2019. (ACTH) hormone infusion was tested in this experiment on acid-base regulation in broiler chickens. For 7 days, osmotic pumps dispensed 8 IU of ACTH in saline/kg of BW/d, or the same volume of saline as in ACTH at 1 l/h. On days 0 and 14, after the beginning of the infusions, blood samples were obtained to establish a baseline. The plasma concentrations of Na+, K+, and Cl- were decreased, whereas the partial pressure of CO2, anion gap, corticosterone, mean corpuscular hemoglobin concentration, and blood concentrations of hemoglobin and HCO - were all elevated due to the ACTH administration. When given ACTH, neither blood pH nor plasma Ca2+ levels changed

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Publication Date
Wed Dec 31 2025
Journal Name
Polymer-plastics Technology And Materials
Comprehensive Study on Structural, Optical, Electrical and Thermal Properties of HPMC/PEG-Li2SO4 Solid Polymer Blend Electrolytes
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In this study, high-performance solid polymer electrolytes (SPEs) with different compositions were investigated for next-generation lithium-based energy storage and flexible electronics technology applications. The SPE films were prepared by the solution casting method using hydroxypropyl methylcellulose (HPMC), polyethylene glycol (PEG), and lithium sulfate (Li2SO4 ). The obtained films were flexible and transparent, hence suitable for structural, optical, electrical, and thermal characterizations. The XRD pattern of HPMC indicated a broad peak at 2 theta approximate to 20 degrees, while the films HPMC/PEG- Li2SO4 showed sharp peaks assigned to the crystalline nature of Li2SO4 . Fourier-transform infrared (FTIR) spectra confirmed O-H vibra

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Publication Date
Mon Sep 13 2021
Journal Name
Eureka: Physics And Engineering
A numerical study to improve the position and angle of the producer gas injector inside the intake manifold to minimize emissions and efficiency enhancement of a bi engine
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To develop a petrol engine so that it works under the bi-engine pattern (producer gas-petrol) without any additional engine modifications, a single-point injection method inside the intake manifold is a simple and inexpensive method. Still, it leads to poor mixing performance between the air and producer gas. This deficiency can cause unsatisfactory engine performance and high exhaust emissions. In order to improve the mixing inside the intake manifold, nine separate cases were modelled to evaluate the impact of the position and angle orientation inside the intake manifold on the uniformity and spread of the mixture under AFR=2.07. A petrol engine (1.6 L), the maximum engine speed (8000 rpm), and bi-engine mode (petrol-producer ga

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Publication Date
Thu Jun 30 2022
Journal Name
نسق
"Flow Theory and Its Role in Education
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Publication Date
Tue Oct 01 2024
Journal Name
Journal Of Engineering Science And Technology
NUMERICAL SIMULATION OF SHEET PILES AS A SEEPAGE CUTTER OFF: AL-KIFIL REGULATOR AS A CASE STUDY
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Sheet piles are necessary with hydraulic structures as seepage cut-off to reduce the seepage. In this research, the computational work methodology was followed by building a numerical model using Geo-Studio program to check the efficiency of using concrete sheet piles as a cut-off or reducer for seepage with time if the sheet piles facing the drawdown technique. Al-Kifil regulator was chosen as a case study, an accurate model was built with a help of observed reading of the measuring devices, which was satisfactory and helped in checking the sheet piles efficiency. Through the study, three scenarios were adopted (with and without) drawdown technique, it was found that at the short time there's no effect of the drawdown technique on

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Publication Date
Sun Jul 20 2025
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study and Investigation of the Charge Transfer Rate Production in N3-Senstized Dye Contact with ZnS Semiconductor System
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In this work, the rate of charge transfer (CT) reaction at the N3-ZnS interface was calculated using a quantitative computational model to evaluate the efficiency of N3-ZnS heterojunction dye-sensitized solar cell devices using different types of solvents. This work discussed the influence of the effective driving energy force on the charge transport rate and performance of N3-ZnS devices with various solvents based on a donor-acceptor model. A solar cell model was used to study the optical efficiency when changing some of its parameters, such as the type of material and the thickness of the film, as they are important factors influencing the quality of the solar cell. It was found that the transition energy varies with different so

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Publication Date
Sun Jun 07 2015
Journal Name
Baghdad Science Journal
The effect of changing the evacuated tube tilt angle and the fluid of the solar collector on the performance of a hybrid solar air conditioning system
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In the hybrid coolingsolar systems , a solar collectoris used to convertsolar energy intoheat sourcein order to super heat therefrigerant leave thecompressor,andthisprocess helpsin the transformation ofrefrigerant state from gaseous statetothe liquid statein upper two-thirdsof thecondenserinstead of the lower two-thirdssuchas in thetraditional air-conditioning systems and this willreduce theenergyneeded torun the process ofcooling.In this research two hybrid air-conditioning system with an evacuated tube solar collector were used, therefrigerant was R22 and the capacity was 2 tons each.The tilt angle of the evacuated tube solar collector was changed and the solar collector fluid was replaced into oil instead of water.A comparison wasi

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Publication Date
Wed Dec 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of Disinfection on Some Properties of Heat-Vulcanized Maxillofacial Silicone Elastomer Reinforced by Nano Silicone Dioxide
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Background: The daily cleaning routine of the silicone maxillofacial prostheses by the patient may cause some alteration in the materials properties. The purpose of the present study was to investigate the effect of different disinfection procedures on some properties of silicon dioxide reinforced Cosmesil M511 HTV maxillofacial silicone. Materials and Methods: One hundred and sixty (160) specimens were prepared by mixing 5% SiO2 nano particles and 0.5% intrinsic cream color into the silicone polymer according to manufacturer's instructions. Specimens were divided into 4 groups according to the performed test (tear strength, surface hardness, surface roughness and color) with 40 specimens each. Each group was further subdivided according to

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