Preferred Language
Articles
/
alkej-211
Effect of Bearing Compliance on Thermo-hydrodynamic Lubrication of High Speed Misaligned Journal Bearing Lubricated with Bubbly Oil
...Show More Authors

Abstract

In the present work  the effect of bearing compliance on the performance of high speed misaligned journal bearing lined with a compliant PTFE liner lubricated with bubbly oil at high speeds has been studied. The effect of induced oil film temperature due to shearing effect has been implemented. Hydrodynamic effect of the complaint bearing and the influence of aerated oil have been examined by the classical thermohydrodynamic lubrication theory modified to include the effect of oil film turbulence and oil film temperature with suitable models for bubbly oil viscosity and density. The effect of liner elastic deformation has been implemented by using Winkler model. The effects of variable density and specific heat on the most importantbearing parameters such as maximum pressure, maximum temperature, bearing load carrying capacity and power losses have been investigated.The results obtained show that the oil film pressure and load carrying capacity increased for the bearing lubricated with bubbly oil of higher aeration level and smaller size of air bubbles. Including the effect of elastic deformation of the bearing liner reduces the oil film pressure, load carrying capacity and frictional power loss for the misaligned bearing working at the same circumstances

Keywords: Journal bearings, hydrodynamic lubrication, THD, compliant effect, bubbly oil, misalignment effect.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Dec 31 2000
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Production of Castor Oil for Medical Uses
...Show More Authors

View Publication Preview PDF
Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Efficiency of Human Resources Information System and Its Impact on The Level Effectiveness of Employees Performance Appraisal System / Practical Research on Ministry of Higher Education and Scientific Research
...Show More Authors

Abstract

The research aims to determine the role of the efficiency of Human Resources Information System in the effectiveness of Employees Performance Appraisal System in the Ministry of Higher Education and Scientific Research / Center for the ministry, it was touching the researchers need the ministry to devise methods that employ outputs Human Resources Information System in the organization surveyed for the development of methods and levels of process evaluate the performance of its employees, in order to identify the extent of the role played by human resources information system in the process of assessing the performance of employees, we raised the question of the President as follows:

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Aug 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Types of the Fiber Glass-Mat on Fatigue Characteristic of Composite Materials at Constant Fiber Volume Fraction: Experimental Determination
...Show More Authors

The aim of this work is to study the influence of the type of fiber glass –mat on fatigue behavior of composite material which is manufactured from polyester and E-glass (woven roving, chopped strand mat (CSM)) as a laminate with a constant fiber volume fraction (VF) of 33%. The results showed that the laminates reinforced with E-glass (woven roving) [0/90, ±45.0/90] and [0/90, CSM, 0/90] have lower fatigue strength than the laminates reinforced with E-glass [0/90]3,[CSM]3 and [CSM, 0/90, CSM]  although they had different tensile strength; the best laminate was [0/90]3 .

View Publication Preview PDF
Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Calibrating the Reservoir Model of the Garraf Oil Field
...Show More Authors

   History matching is a significant stage in reservoir modeling for evaluating past reservoir performance and predicting future behavior. This paper is primarily focused on the calibration of the dynamic reservoir model for the Meshrif formation, which is the main reservoir in the Garraf oilfield. A full-field reservoir model with 110 producing wells is constructed using a comprehensive dataset that includes geological, pressure-volume-temperature (PVT), and rock property information. The resulting 3D geologic model provides detailed information on water saturation, permeability, porosity, and net thickness to gross thickness for each grid cell, and forms the basis for constructing the dynamic reservoir model. The dynamic reservoir mo

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Oct 08 2002
Journal Name
Iraqi Journal Of Laser
Visible Enhanced Photodetector Made by Spray Pyrolysis
...Show More Authors

Barium–doped TiO2 / n-Si photodetector was fabricated by spray pyrolysis exhibited visible enhancement responsivity profile with peak response at 600 nm flat response between 650 and 900 nm. The quantum efficiency was 30% and specific detectivity was 5x1012 W-1Hz1/2cm at peak response. The GaAlAs laser diode was used to estimate the rise time of the detector.

View Publication Preview PDF
Publication Date
Sun Jul 03 2016
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Danials model in concepts Acquisition of Education Principles on Studets at college of Education .
...Show More Authors

The research aims at identifyiny the effect of (Danials Model) in concepts Acquisition of Education Principles on Students at college at Education The total unmber of Students , is (65) male and female Students distributed in two groups . The First group is the experiemental group which is taught the (Danials Model) and is (34) Students . The second groupe is the control group which is taught the traditional method of teaching and it is (31) Students . The researcher has matcheol between the two groupe by the following variables : the age , (in monthes) their intelligence their parents a cademic leve of education . The research has constructed a test of (20) items of multiple choice test . The reliability of The test has been cal

... Show More
View Publication Preview PDF
Publication Date
Sun Apr 30 2023
Journal Name
Al-kindy College Medical Journal
The Ameliorating Effect of Ashwagandha (Withania Somnifera) Extract on Hippocampus and Growth Plate Changes Associated With Propylthiouracil Induced Hypothyroidism in Juvenile Rats : Ashwagandha on Hippocampus and Growth Plate Changes Associated With hypothyroid rats
...Show More Authors

Background: Hypothyroidism is a decrease in the production of the thyroid hormones and leads to gland dysfunction. Ashwagandha extract was used as an ayurvedic treatment and supposed to be as antihypothyroidism agent.

Objectives: to investigate the impact of ashwagandha (Ash) extract on propylthiouracil (PTU)-induced hypothyroidism in rats.

Subjects and Methods: The rats were divided into three groups, control group, PTU (hypothyroid) group (6mg/kg/day by oral route), PTU (6mg/kg/day by oral route) +Ash (50mg/kg/day by oral route) treated group. All treatment continued for

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (4)
Scopus Crossref
Publication Date
Sat Apr 03 2021
Journal Name
Lubricants
UV-Visible Spectrophotometer for Distinguishing Oxidation Time of Engine Oil
...Show More Authors

Samples of gasoline engine oil (SAE 5W20) that had been exposed to various oxidation times were inspected with a UV-Visible (UV-Vis) spectrophotometer to select the best wavelengths and wavelength ranges for distinguishing oxidation times. Engine oil samples were subjected to different thermal oxidation periods of 0, 24, 48, 72, 96, 120, and 144 hours, resulting in a range of total base number (TBN) levels. Each wavelength (190.5 – 849.5 nm) and selected wavelength ranges were evaluated to determine the wavelength or wavelength ranges that could best distinguish among all oxidation times. The best wavelengths and wavelength ranges were analyzed with linear regression to determine the best wavelength or range to predict oxidation t

... Show More
View Publication Preview PDF
Scopus (19)
Crossref (19)
Scopus Clarivate Crossref
Publication Date
Sun Dec 30 2018
Journal Name
Journal Of Engineering
Effect of bentonite addition on some properties of porcelain
...Show More Authors

Porcelain is one of the most important ceramic materials with a wide range of traditional and technical applications. Since most mixtures of porcelain have a high sintering temperature, bentonite has been added in this research to improve the characteristics of sintering and burning. The porcelain mixture consisted of the following Iraqi raw materials: 30% wt kaolin, 30 wt% non-plastic clay (grog), 10% wt sodium feldspar, 10 wt% potassium feldspar and 20 wt% flint. After the mechanical mixing process and transfer the powder mixture to the slurry by adding distilled water, then different weight percentage of the sodium bentonite(0, 2.5, 5, 7.5 and 10) wt% was added. The specimens were prepared by using the solid casting m

... Show More
View Publication Preview PDF
Crossref (8)
Crossref
Publication Date
Mon Feb 01 2021
Journal Name
Materials Science And Engineering
Effect of magnetic water on strength properties of concrete
...Show More Authors
Abstract<p>The research’s main goal is to investigate the effects of using magnetic water in concrete mixes with regard to various mechanical properties such as compressive, flexural, and splitting tensile strength. The concrete mix investigated was designed to attain a specified cylinder compressive strength (30 MPa), with mix proportions of 1:1.8:2.68 cement to sand to crushed aggregate. The cement content was about 380 kg/m<sup>3</sup>, with a w/c ratio equal to 0.54, sand content of about 685 kg/m3, and gravel content of about 1,020 kg/m3. Magnetic water was prepared via passing ordinary water throughout a magnetic field with a magnetic intensity of 9,000 Gauss. The strength test</p> ... Show More
Crossref (7)
Crossref