Preferred Language
Articles
/
ijcpe-418
Mixed convection in an Horizontal Rectangular Duct Including interior Circular Core with Time periodic Boundary Condition
...Show More Authors

Numerical Investigation was done for steady state laminar mixed convection and thermally and hydrodynamic fully developed flow through horizontal rectangular duct including circular core with two cases of time periodic boundary condition, first case  on the rectangular wall while keeping core wall constant and other on both the rectangular duct and core walls. The used governing equations are continuity momentum and energy equations. These equations are normalized and solved using the Vorticity-Stream function and the Body Fitted Coordinates (B.F.C.) methods. The Finite Difference approach with the Line Successive Over Relaxation (LSOR) method is used to obtain all the computational results the (B.F.C.) method is used to generate the grid of the problem. A computer program (Fortan 90) is built to calculate Nusselt Number (Nu) in steady state. The fluid Prandtl number is 0.7 Rayleigh Number  1<Ra<106, Reynolds number 1<Re<2000. For the range of parameters considered, results show that the time periodic boundary condition enhance heat transfer. It is also indicated in the results that heat transfer from the surface of the circle exceeds that of the rectangle duct. Comparisons with other research show good agreement.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
On The Dynamical Behavior of a Prey-Predator Model With The Effect of Periodic Forcing
...Show More Authors

The dynamical behavior of a two-dimensional continuous time dynamical system describing by a prey predator model is investigated. By means of constructing suitable Lyapunov functional, sufficient condition is derived for the global asymptotic stability of the positive equilibrium of the system. The Hopf bifurcation analysis is carried out. The numerical simulations are used to study the effect of periodic forcing in two different parameters. The results of simulations show that the model under the effects of periodic forcing in two different parameters, with or without phase difference, could exhibit chaotic dynamics for realistic and biologically feasible parametric values.

View Publication Preview PDF
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
On some types of almost periodic point in Bi-Topological dynamcs
...Show More Authors

In this paper We introduce some new types of almost bi-periodic points in topological bitransfprmation groups and thier effects on some types of minimaliy in topological dynamics

View Publication Preview PDF
Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
A GENERAL VELOCITY PROFILE FOR A LAMINAR BOUNDARY LAYER OVER FLAT PLATE WITH ZERO INCIDENCE
...Show More Authors

A general velocity profile for a laminar flow over a flat plate with zero incidence is obtained by employing a new boundary condition to the other available boundary conditions. The general velocity profile is mathematically simple and nearest to the exact solution. Also other related values, boundary layer thickness, displacement thickness, momentum thickness and coefficient of friction are nearest to the exact solution compared with other corresponding values for other researchers.

View Publication Preview PDF
Crossref
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Compression of an ECG Signal Using Mixed Transforms
...Show More Authors

Electrocardiogram (ECG) is an important physiological signal for cardiac disease diagnosis. With the increasing use of modern electrocardiogram monitoring devices that generate vast amount of data requiring huge storage capacity. In order to decrease storage costs or make ECG signals suitable and ready for transmission through common communication channels, the ECG data
volume must be reduced. So an effective data compression method is required. This paper presents an efficient technique for the compression of ECG signals. In this technique, different transforms have been used to compress the ECG signals. At first, a 1-D ECG data was segmented and aligned to a 2-D data array, then 2-D mixed transform was implemented to compress the

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Dec 28 2017
Journal Name
Al-khwarizmi Engineering Journal
An Autocorrelative Approach for EMG Time-Frequency Analysis
...Show More Authors

As they are the smallest functional parts of the muscle, motor units (MUs) are considered as the basic building blocks of the neuromuscular system. Monitoring MU recruitment, de-recruitment, and firing rate (by either invasive or surface techniques) leads to the understanding of motor control strategies and of their pathological alterations. EMG signal decomposition is the process of identification and classification of individual motor unit action potentials (MUAPs) in the interference pattern detected with either intramuscular or surface electrodes. Signal processing techniques were used in EMG signal decomposition to understand fundamental and physiological issues. Many techniques have been developed to decompose intramuscularly detec

... Show More
View Publication Preview PDF
Publication Date
Mon Dec 18 2017
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Magnetic Field with Nanofluid on Heat Transfer in a Horizontal Pipe
...Show More Authors

This work presents an experimental study of heat transfer and flow of distilled water and metal oxide nanofluid Fe3O4-distilled water at concentrations of (φ = 0.3, 0.6, 0.9 %) by volume in a horizontal pipe with constant magnetic field. All the tests are carried out with Reynolds number range (2900-9820) and uniform heat flux (11262-19562 W/m2). The results show that, the nanofluid concentration and magnetic intensity increase, the Nusselt number increases. The maximum enhancement in Nusselt number with magnetic nanofluid is (5.4 %, 26.4 %, 42.7 %) for volume concentration (0.3, 0.6, 0.9 %) respectively. The enhancement is maximized with magnetic intensity (0.1, 0.2, 0.3 tesla) respectively to (43.9, 44

... Show More
View Publication Preview PDF
Publication Date
Sat Dec 31 2022
Journal Name
Journal Of Economics And Administrative Sciences
Comparison of Robust Circular S and Circular Least Squares Estimators for Circular Regression Model using Simulation
...Show More Authors

In this paper, the Monte-Carlo simulation method was used to compare the robust circular S estimator with the circular Least squares method in the case of no outlier data and in the case of the presence of an outlier in the data through two trends, the first is contaminant with high inflection points that represents contaminant in the circular independent variable, and the second the contaminant in the vertical variable that represents the circular dependent variable using three comparison criteria, the median standard error (Median SE), the median of the mean squares of error (Median MSE), and the median of the mean cosines of the circular residuals (Median A(k)). It was concluded that the method of least squares is better than the

... Show More
View Publication
Crossref
Publication Date
Tue Aug 06 2024
Journal Name
Journal Of Thermal Analysis And Calorimetry
Al2O3–Cu hybrid nanofluid flow and heat transfer characteristics in the duct with various triangular rib configurations
...Show More Authors

View Publication
Scopus (9)
Crossref (9)
Scopus Crossref
Publication Date
Sat Feb 27 2021
Journal Name
Journal Of Engineering
Physical Simulation for the Flow in Straight and Rectangular Loop Manifolds
...Show More Authors

The flow in a manifolds considered as an advanced problem in hydraulic engineering applications. The objectives of this study are to determine; the uniformity qn/q1 (ratio of the discharge at last outlet, qn to the discharge at first outlet, q1) and total head losses of the flow along straight and rectangular loop manifolds with different flow conditions. The straight pipes were with 18 m and 19 m long and with of 25.4 mm (1.0 in) in diameter each. While, the rectangular close loop configuration was with length of 19 m and with diameter of 25.4 mm (1.0 in) also. Constant head in the supply tank was used and the head is 2.10 m. It is found that outlets spacing and manifold configuration are the main factors aff

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Thu Oct 01 2020
Journal Name
International Communications In Heat And Mass Transfer
Thermal behaviour of the flow boiling of a complex nanofluid in a rectangular channel: An experimental and numerical study
...Show More Authors

View Publication
Scopus (28)
Crossref (25)
Scopus Clarivate Crossref