A numerical investigation has been performed to study the effect of eccentricity on unsteady state, laminar aiding mixed convection in a horizontal concentric and eccentric cylindrical annulus. The outer cylinder was kept at a constant temperature
while the inner cylinder was heated with constant heat flux. The study involved numerical solution of transient momentum (Navier-Stokes) and energy equation using finite difference method (FDM), where the body fitted coordinate system (BFC) was
used to generate the grid mesh for computational plane. The governing equations were transformed to the vorticity-stream function formula as for momentum equations and to the temperature and stream function for energy equation.
A computer program (Fortran 90) was built to calculate the bulk Nusselt number (Nub) after reaching steady state condition for fluid Prandtl number fixed at 0.7 (air) with radius ratio ( =2.6), Rayleigh number (Ra=200), Reynolds number (Re=50) for both concentric and eccentric cylindrical annulus with different eccentricity ratios (ε=0, 0.25, 0.50, 0.75) and angular positions (φo=0o
, 45o , 90o , 135o , 180o ).
The results show a reasonable representation to the relation between Nusselt number and (ε, φo). Generally, Nub decreased with the increase in (ε and φo). Also, results show that the best thermal performance for the inner cylinder was at the angular
position (φo=0o ) for eccentricity ratio (ε=0.25), while the maximum reduction in the rate of heat transfer for the inner cylinder was at the angular position (φo=180o) for eccentricity ratio (ε=0.75).
Comparison of the result with the previous work shows a good agreement.
Turkey Consider Tigris and Euphrates rivers as a national rivers, and not an a International rivers, so that . It insists on its absolute sovereignty on that resources. The block ( levee ) which Turkey established should not create International problems.
The All International agreements and laws in this sect warrant the rights of all the states that located in river stream to use it without any consider to the regional absolute right.
During the 1980s, Turkey construct water projects, started with GAP, project which is one of the greatest project in the world, in spite of the plane of construct of the keep an levee on the Euphrates was pre of that project. The
... Show MoreThe study aims at fathoming Robert Browning’ and Robert Lowell’s intentions of choosing the dramatic monologue as a means of exploring human psyche. Significantly, the themes of insanity and murder are not ideal from an esthetic perspective, but for Browning and Lowell it provides the key to probe into human character and fundamental motives. This study examines Browning’ and Lowell’s dramatic monologues that address crime and the psyche of abnormal men. Browning’ and Lowell’s poetry in this regard unravels complicated human motivations and delineates morbid psychologies. Their monologues probe deep down into the mind-sets of their characters and dissect their souls to the readers. The main character of each of Browning
... Show MoreConstitute the relationship between the director and actor mainstay chock done to show art in film and television , both of which occupy what a big role in the mission accomplishment . The leadership of the director of the artwork in various joints require two features two important ( creativity and administration ) , The capabilities director of creative serves as an added intellectual and aesthetic saturated sensation that leaves its impact on all the technical elements involved in done. Either trait administration and leadership it is what requires multiple skills in dealing on according to technical standards and moral and humanitarian allow the transfer of ideas , concepts and visions to those elements to embody and implement the ki
... Show MoreBackground Rectal cancer is one of the most common malignant tumors of gastrointestinal tract. Combining chemotherapy with radiotherapy has a sound effect on its management.
Objectives Assessment the patterns of characterizations of rectal cancer. Evaluation of the efficacy, and long-term survival of pre-/ postoperative chemoradiation. Collecting all eligible evidence articles and summarize the results.
Methods By this systematic review and meta-analysis study, we include data of chemoradiation of rectal cancer articles from 2015 until 2019. The research was carried out at Baghdad Medical City oncology centers. Accordance with the
Throughout Agriculture has mostly relied on the use of natural fertilizers throughout human history, which are compounds that increase the nitrogen levels in the soil. Modern agriculture was made possible by the introduction of synthetic fertilizers at the end of the 19th centuryproduction of agriculture. Their application enhanced crop yields and sparked an agricultural revolution unlike anything the world had ever seen.In the near future, synthetic fertilizers are anticipated to continue to have a significant impa ct on human life, both positively and negatively. They are frequently utilized for producing all t ypes of crops and are essential to plant growth. The significance of synthetic fertilizers is their ability to provide the soil w
... Show MoreAbstract
This research aims to design a multi-objective mathematical model to assess the project quality based on three criteria: time, cost and performance. This model has been applied in one of the major projects formations of the Saad Public Company which enables to completion the project on time at an additional cost that would be within the estimated budget with a satisfactory level of the performance which match with consumer requirements. The problem of research is to ensure that the project is completed with the required quality Is subject to constraints, such as time, cost and performance, so this requires prioritizing multiple goals. The project
... Show MoreThe analytical study of optical bistability is concerned in a fully
optimized laser Fabry-Perot system. The related phenomena of
switching dynamics and optimization procedure are also included.
From the steady state of optical bistability equation can plot the
incident intensity versus the round trip phase shift (φ) for different
values of dark mistuning
12
,
6
,
3
,
1.5
0 , o
or finesse (F= 1, 5, 20,
100). In order to obtain different optical bistable loops. The inputoutput
characteristic for a nonlinear Fabry-Perot etalon of a different
values of finesse (F) and using different initial detuning (φ0) are used
in this rese
This study presents a mathematical model describing the interaction of gut bacteria in the participation of probiotics and antibiotics, assuming that some good bacteria become harmful through mutations due to antibiotic exposure. The qualitative analysis exposes twelve equilibrium points, such as a good-bacteria equilibrium, a bad-bacteria equilibrium, and a coexisting endemic equilibrium in which both bacteria exist while being exposed to antibiotics. The theory of the Sotomayor theorem is applied to study the local bifurcation around all possible equilibrium points. It’s noticed that the transcritical and saddle-node bifurcation could occur near some of the system’s equilibrium points, while pitchfork bifurcation cannot be accrued at
... Show MoreThe present study analyzes the effect of couple stress fluid (CSF) with the activity of connected inclined magnetic field (IMF) of a non-uniform channel (NUC) through a porous medium (PM), taking into account the sliding speed effect on channel walls and the effect of nonlinear particle size, applying long wavelength and low Reynolds count estimates. The mathematical expressions of axial velocity, stream function, mechanical effect and increase in pressure have been analytically determined. The effect of the physical parameter is included in the present model in the computational results. The results of this algorithm have been presented in chart form by applying the mathematical program.