Preferred Language
Articles
/
joe-2147
PARAMETRIC STUDY OF LAMINAR FREE CONVECTION IN INCLINED POROUS ANNULUS WITH FINS ON THE INNER CYLINDER
...Show More Authors

An experimental and numerical study has been carried out to investigate the heat transfer by natural convection in a three dimensional annulus enclosure filled with porous media (silica sand) between two inclined concentric cylinders with (and without) annular fins attached to the inner cylinder under steady state condition; The experiments were carried out for a range of modified Rayleigh number (0.2 ≤Ra*≤ 11) and extended to Ra* =500 for numerical study, annulus inclination angle of (δ = 0˚, 30˚, 60˚ and 90˚). The numerical study was to write the governing equation under an assumptions used Darcy law and Boussinesq’s approximation and then solved numerically using finite difference approximation. It was found that the average Nusselt number depends on (Ra*, Hf, δ and Rr) and the maximum value of the local Nusselt number for vertical cylinder is about two times as large as that of the horizontal case. The results showed that, increasing of fin length increases the heat transfer rate for any fins pitch unless the area of the inner cylinder exceeds that of the outer one, then the heat will be stored in the porous media. A correlation for Nu in terms of Ra, Rr and δ, has been developed for inner cylinder. A comparison was made between the results of the present work and with other researches for the case without fins and excellent agreement was obtained and reveals deviation less than 5 % for average Nusselt number.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Semi parametric Estimators for Quantile Model via LASSO and SCAD with Missing Data
...Show More Authors

In this study, we made a comparison between LASSO & SCAD methods, which are two special methods for dealing with models in partial quantile regression. (Nadaraya & Watson Kernel) was used to estimate the non-parametric part ;in addition, the rule of thumb method was used to estimate the smoothing bandwidth (h). Penalty methods proved to be efficient in estimating the regression coefficients, but the SCAD method according to the mean squared error criterion (MSE) was the best after estimating the missing data using the mean imputation method

View Publication Preview PDF
Crossref
Publication Date
Sun Dec 31 2000
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Preparation of Zeolite 4A and Studying the Operating Conditions of the Agglomeration in the Inclined Rotary Disk
...Show More Authors

View Publication Preview PDF
Publication Date
Thu Sep 08 2022
Journal Name
Al-khwarizmi Engineering Journal
Kinetics of Electrochemical Removal of Nickel using Bio-electrochemical Reactor with Packed Bed Rotating Cylinder Cathode
...Show More Authors

The kinetics of nickel removal from aqueous solutions using a bio-electrochemical reactor with a packed bed rotating cylinder cathode was investigated. The effects of applied voltage, initial nickel concentration, the rotation speed of the cathode, and pH on the reaction rate constant (k) were studied. The results showed that the cathodic deposition occurred under mass transfer control for all values of the applied voltage used in this research. Accordingly, the relationship between concentration and time can be represented by a first-order equation. The rate constant was found to be dependent on the applied voltage, initial nickel concentration, pH, and rotation speed. It was increased as the applied voltage increased and decreased as t

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Wed May 10 2023
Journal Name
Journal Of Engineering
Free Head Shear Test on Decomposed Granite Soil
...Show More Authors

The study presents the test results of Completely Decomposed Granite (CDG) soil tested under drained triaxial compression, direct shear and simple shear tests. Special attention was focused on the modification of the upper halve of conventional Direct Shear Test (DST) to behave as free
head in movement along with vertical strain control during shear stage by using Geotechnical Digital System (GDS). The results show that Free Direct Shear Test (FDST) has clear effect on the measured shear stress and vertical strain during the test. It has been found that shear strength
parameters measured from FDST were closer to those measured from simple shear and drained triaxial compression test. This study also provides an independent check on

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed May 10 2023
Journal Name
Journal Of Engineering
An Investigation into Heat Transfer Enhancement by Using Oscillating Fins
...Show More Authors

The present work describes numerical and experimental investigation of the heat transfer characteristics in a plate-fin, having built-in piezoelectric actuator mounted on the base plate (substrate). The geometrical configuration considered in the present work is representative of a single element of the plate-fin and triple fins. Air is taken as the working fluid. A performance data for a single rectangular fin and triple fins are provided for different frequency levels (5, 30 and
50HZ) , different input power (5,10,20,30,40 and 50W) and different inlet velocity (0.5, 1, 2, 3, 4, 5 and 6m/s) for the single rectangular fin and triple fins with and without oscillation. The investigation was also performed with different geometrical fin

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jan 01 2016
Journal Name
Isi Bilimi Ve Teknigi Dergisi/ Journal Of Thermal Science And Technology,
Enhancement of natural convection heat transfer of pin fin having perforated with inclination angle
...Show More Authors

Scopus (4)
Scopus
Publication Date
Thu Nov 11 2021
Journal Name
Iraqi Journal Of Science
Impacts of porous medium on unsteady helical flows of generalized oldroyd-B fluid with two infinite coaxial circular cylinders
...Show More Authors

Scopus (7)
Scopus
Publication Date
Tue Dec 01 2009
Journal Name
Iraqi Journal Of Physics
Study of Some Structural Properties of Porous Silicon Preparing by Photochemical Etching
...Show More Authors

Abstract:Porous Silicon (PSi) has been produced in this work by using Photochemical (PC) etching process by using a hydrofluoric acid (HF) solution. The irradiation has been achieved using quartz- tungsten halogen lamp. The influence of various irradiation times on the properties of PSi اmaterial such as layer thickness, etching rate and porosity was investigated in this work too. The XRD has been studied to determine the crystal structure and the crystalline size of PSi material

Preview PDF
Publication Date
Mon Mar 23 2020
Journal Name
Journal Of Engineering
Experimental Investigation of Thermal Performance of a Solar Chimney Provided with a Porous Absorber Plate
...Show More Authors

 

Experimental investigation of the influence of inserting the metal foam to the solar chimney to induce natural ventilation are described and analyzed in this work. To carry out the experimental test, two identical solar chimneys (without insertion of metal foam and with insertion of metal foam) are designed and placed facing south with dimensions of length× width× air gap (2 m× 1 m× 0.2 m). Four incline angles are tested (20o,30o,45o,60o) for each chimney in Baghdad climate condition (33.3o latitude, 44.4o longitude) on October, November, December 2018. The solar chimney performance is investigated by experimentally recording absorber pl

... Show More
View Publication Preview PDF
Crossref (5)
Crossref
Publication Date
Mon Oct 02 2023
Journal Name
Journal Of Polymer Research
Morphological study of porous aromatic schiff bases as a highly effective carbon dioxide storages
...Show More Authors

Carbon dioxide (CO2) capture and storage is a critical issue for mitigating climate change. Porous aromatic Schiff base complexes have emerged as a promising class of materials for CO2 capture due to their high surface area, porosity, and stability. In this study, we investigate the potential of Schiff base complexes as an effective media for CO2 storage. We review the synthesis and characterization of porous aromatic Schiff bases materials complexes and examine their CO2 sorption properties. We find that Schiff base complexes exhibit high CO2 adsorption capacity and selectivity, making them a promising candidate for use in carbon capture applications. Moreover, we investigate the effect of various parameters such as temperature, and pressu

... Show More