Preferred Language
Articles
/
alkej-77
Experimental Estimation of Critical Buckling Velocities for Conservative Pipes Conveying Fluid
...Show More Authors

Conservative pipes conveying fluid such as pinned-pinned (p-p), clamped–pinned (c-p) pipes and clamped-clamped (c-c) lose their stability by buckling at certain critical fluid velocities. In order to experimentally evaluate these velocities, high flow-rate pumps that demand complicated fluid circuits must be used.

     This paper studies a new experimental approach based on estimating the critical velocities from the measurement of several fundamental natural frequencies .In this approach low flow-rate pumps and simple fluid circuit can be used.

Experiments were carried out on two pipe models at three different boundary conditions. The results showed that the present approach is more accurate for estimating the critical velocities of p-p and c-p pipes. However, for c-c pipes it was not so unless a higher flow rate is used.

 

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Sep 01 2014
Journal Name
Al-khwarizmi Engineering Journal
Experimental Performance of a Finned-tube Silica Gel Adsorption Chiller for Air-Conditioning Application
...Show More Authors

This work presents the construction of a test apparatus for air-conditioning application that is flexible in changing a scaled down adsorbent bed modules. To improve the heat and mass transfer performance of the adsorbent bed, a finned-tube of the adsorbent bed heat exchanger was used. The results show that the specific cooling power (SCP) and the coefficient of performance (COP) are 163 W/kg and 0.16, respectively, when the cycle time is 40 min, the hot water temperature is 90oC, the cooling water temperature is 30oC and the evaporative water temperature is 11.4oC.

View Publication Preview PDF
Publication Date
Tue Nov 08 2022
Journal Name
Buildings
An Experimental Study of Granular Material Using Recycled Concrete Waste for Pavement Roadbed Construction
...Show More Authors

Rapid worldwide urbanization and drastic population growth have increased the demand for new road construction, which will cause a substantial amount of natural resources such as aggregates to be consumed. The use of recycled concrete aggregate could be one of the possible ways to offset the aggregate shortage problem and reduce environmental pollution. This paper reports an experimental study of unbound granular material using recycled concrete aggregate for pavement subbase construction. Five percentages of recycled concrete aggregate obtained from two different sources with an originally designed compressive strength of 20–30 MPa as well as 31–40 MPa at three particle size levels, i.e., coarse, fine, and extra fine, were test

... Show More
View Publication
Scopus (13)
Crossref (12)
Scopus Clarivate Crossref
Publication Date
Sat Dec 02 2023
Journal Name
Journal Of Engineering
Simulation and Experimental Investigation of Performance and Flow Behavior for Steam Ejector Refrigeration System
...Show More Authors

The ejector refrigeration system is a desirable choice to reduce energy consumption. A Computational Fluid Dynamics CFD simulation using the ANSYS package was performed to investigate the flow inside the ejector and determine the performance of a small-scale steam ejector. The experimental results showed that at the nozzle throat diameter of 2.6 mm and the evaporator temperature of 10oC, increasing boiler temperature from 110oC to 140oC decreases the entrainment ratio by 66.25%. At the boiler temperature of 120oC, increasing the evaporator temperature from 7.5 to 15 oC increases the entrainment ratio by 65.57%. While at the boiler temperature of 120oC and

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat Aug 17 2024
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
Analysis of Follicular Fluid Fatty Acids in Iraqi Women Undergoing Intracytoplasmic Sperm Injection
...Show More Authors

Background: Oocytes are susceptible to alterations in the various fatty acid contents of follicular fluid (FF), which may influence maturation and embryogenesis. Different fatty acids exert various effects on intracytoplasmic sperm injection (ICSI), which needs further studies to uncover the involved mechanisms. Objectives: To assess FF fatty acids in women undergoing ICSI and to correlate them with ICSI parameters, namely the total count of aspirated oocytes, oocyte maturation rate, fertilization rate and percentage of good-quality embryos. Methods: Fifty women undergoing ICSI were enrolled in this cross-sectional study. FF samples were collected during oocyte retrieval and were analyzed for fatty acids using gas chromatography. Fa

... Show More
View Publication
Scopus Crossref
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Steady and unsteady flow of non-newtonian fluid in curved pipe with triangular
...Show More Authors

This paper deals with numerical study of the flow of stable and fluid Allamstqr Aniotina in an area surrounded by a right-angled triangle has touched particularly valuable secondary flow cross section resulting from the pressure gradient In the first case was analyzed stable flow where he found that the equations of motion that describe the movement of the fluid

View Publication Preview PDF
Publication Date
Sun Dec 02 2012
Journal Name
Baghdad Science Journal
Unsteady Magnetohydrodynamics oscillating flow of third order fluid with central free stream velocity
...Show More Authors

In this article the unsteady magnetohydrodynamics oscillating flow of third order fluid with free stream velocity is proposed. It is found that the motion equation is controlled by five dimensionless parameters namely the coecostic parameter 4, viscoelostic parameter ?,acceleration/deceleration c,suction/blowing d and material constants ? . The effect of each of these parameters upon the velocity distribution is analysised

View Publication Preview PDF
Crossref
Publication Date
Sat Aug 17 2024
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
Analysis of Follicular Fluid Fatty Acids in Iraqi Women Undergoing Intracytoplasmic Sperm Injection
...Show More Authors

Background: Oocytes are susceptible to alterations in the various fatty acid contents of follicular fluid (FF), which may influence maturation and embryogenesis. Different fatty acids exert various effects on intracytoplasmic sperm injection (ICSI), which needs further studies to uncover the involved mechanisms. Objectives: To assess FF fatty acids in women undergoing ICSI and to correlate them with ICSI parameters, namely the total count of aspirated oocytes, oocyte maturation rate, fertilization rate and percentage of good-quality embryos. Methods: Fifty women undergoing ICSI were enrolled in this cross-sectional study. FF samples were collected during oocyte retrieval and were analyzed for fatty acids using gas chromatography. Fa

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Thu Oct 31 2013
Journal Name
Al-khwarizmi Engineering Journal
Aeroelastic Behavior of a Wind Turbine Blade by a Fluid -Structure Interaction Analysis
...Show More Authors

In this paper, a numerical model for fluid-structure interaction (FSI) analysis is developed for investigating the aeroelastic response of a single wind turbine blade. The Blade Element Momentum (BEM) theory was adopted to calculate the aerodynamic forces considering the effects of wind shear and tower shadow. The wind turbine blade was modeled as a rotating cantilever beam discretized using Finite Element Method (FEM) to analyze the deformation and vibration of the blade. The aeroelastic response of the blade was obtained by coupling these aerodynamic and structural models using a coupled BEM-FEM program written in MATLAB. The governing FSI equations of motion are iteratively calculated at each time step, through exchanging data between

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 01 2023
Journal Name
Al-khwarizmi Engineering Journal
Expired Colxacillin, Amoxicillin, and Ceflaxin Drugs as Inhibitors for Low Carbon Steel Corrosion in Sodium Chloride
...Show More Authors

The ability to inhibit corrosion of low carbon steel in a salt solution (3.5%NaCl) has been checked with three real expired drugs (Cloxacillin, Amoxicillin, Ceflaxin) with variable concentrations (0, 250, 500, 750) mg/L were examined in the weight loss. The inhibition efficiency of the Cloxacillin 750 mg/L showed the highest value (82.8125 %) and the best inhibitor of the rest of the antibiotics. The different concentrations of Cloxacillin drug (0, 250, 500, 750) mg/L and temperature (25, 35, 45, 55) oC were studied as variables with potentiodynamic polarization, Scanning Electron Microscopy (SEM) for surface morphology and electrochemical impedance spectroscopy (EIS) depending on current values and the resistance of charge to

... Show More
View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Experimental and Numerical Investigation for Simulation of Thermophysical Properties for Polypropylene 575 Polymer Melts in Single Screw Extruder
...Show More Authors

A numerical model for Polypropylene 575 polymer melts flow along the solid conveying screw of a single screw extruder under constant heat flux using ANSYS-FLUENT 17.2 software has been conducted. The model uses the thermophysical properties such as Viscosity, thermal conductivity, Specific heat and density of polypropylene 575 that measured as a function of temperature, and residence time data for process simulation. The numerical simulation using CFD models for single screw extruder and the polymer extrusion was analysed for parameters such as (thermal conductivity, specific heat, density and viscosity) reveals a high degree of similarity to experimental data measured. The most important outcome of this study is that geometrical, parame

... Show More
View Publication Preview PDF
Crossref