Preferred Language
Articles
/
GBedRo4BVTCNdQwCiEB8
Experimental study of natural convection heat transfer on an enclosure partially filled porous medium heated from below by constant heat flux
...Show More Authors

This study reports on natural convection heat transfer in a square enclosure of length (L=20 cm) with a saturated porous medium (solid glass beads) having same fluid (air) at lower horizontal layer and free air fill in the rest of the cavity's space. The experimental work has been performed under the effects of heating from bottom by constant heat flux q=150,300,450,600 W/m2 for four porous layers thickness Hp (2.5,5,7.5,1) cm and three heaters length δ(20,14,7) cm. The top enclosure wall was good insulated and the two side walls were symmetrically cooled at constant temperature. Four layers of porous media with small porosity, Rayleigh number range (60.354 - 241.41) and (Da) 3.025x10-8 has been investigated. The obtained data of temperature from testing rig are used to extract the temperature distribution, local Nusselt number and average Nusselt number. Moreover, a comparison between the numerical result of the same problem published recently and present experimental results has been executed and discussed. It is evinced that; the heat transfer and fluid flow are affected by thickness of porous layer and be maximum at porous layer thickness (0.25L) with larger heater length(20cm) and heat flux (q= 600 Watt/m2) which is approximately (180%) for the average Nu when compared with (Hp=0.75L). Also, the effect of the increasing in heater length (δ) on the averaged heat transfer enhancement is more pronounced for large heater size and 25% of average enhancement is achieved for (δ=20cm) compared to (δ=7cm). However, the greater temperature distribution is found at Hp=2.5cm and 5cm at bottom and first quarter of the cavity (heater surface height Y=0 cm and Y=5 cm) respectively and minimum temperature at top (insulation wall Y=20 cm). Nearly, same shape for heat transfer for different case with clearly difference at small heater (δ=7cm).

Scopus Crossref
View Publication
Publication Date
Fri Apr 01 2022
Journal Name
Baghdad Science Journal
On Hereditarily Codiskcyclic Operators
...Show More Authors

Many codiskcyclic operators on infinite-dimensional separable Hilbert space do not satisfy the criterion of codiskcyclic operators. In this paper, a kind of codiskcyclic operators satisfying the criterion has been characterized, the equivalence between them has been discussed and the class of codiskcyclic operators satisfying their direct summand is codiskcyclic. Finally, this kind of operators is used to prove that every codiskcyclic operator satisfies the criterion if the general kernel is dense in the space.

View Publication Preview PDF
Scopus (3)
Scopus Clarivate Crossref
Publication Date
Sun Mar 01 2020
Journal Name
Baghdad Science Journal
On S*-Supplemented Modules
...Show More Authors

The main goal of this paper is to introduce and study a new concept named d*-supplemented which can be considered as a generalization of W- supplemented modules and d-hollow module. Also, we introduce a d*-supplement submodule. Many relationships of d*-supplemented modules are studied. Especially, we give characterizations of d*-supplemented modules and relationship between this kind of modules and other kind modules for example every d-hollow (d-local) module is d*-supplemented and by an example we show that the converse is not true.

View Publication Preview PDF
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
On Semi-?-Connected Subspace
...Show More Authors

In this paper, the concept of semi-?-open set will be used to define a new kind of strongly connectedness on a topological subspace namely "semi-?-connectedness". Moreover, we prove that semi-?-connectedness property is a topological property and give an example to show that semi-?-connectedness property is not a hereditary property. Also, we prove thate semi-?-irresolute image of a semi-?-connected space is a semi-?-connected space.

View Publication Preview PDF
Crossref
Publication Date
Fri Mar 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On Semi-Essential Submodules
...Show More Authors

Let R be a commutative ring with identity and let M be a unitary left R-module. The purpose of this paper is to investigate some new results (up to our knowledge) on the concept of semi-essential submodules which introduced by Ali S. Mijbass and Nada K. Abdullah, and we make simple changes to the definition relate with the zero submodule, so we say that a submodule N of an R-module M is called semi-essential, if whenever N ∩ P = (0), then P = (0) for each prime submodule P of M. Various properties of semi-essential submodules are considered.

View Publication Preview PDF
Publication Date
Tue Feb 01 2022
Journal Name
Iraqi Journal Of Science
On Closed Rickart Modules
...Show More Authors

In this article, we study the notion of closed Rickart modules. A right R-module M is said to be closed Rickart if, for each , is a closed submodule of M. Closed Rickart modules is a proper generalization of Rickart modules. Many properties of closed Rickart modules are investigated. Also, we provide some characterizations of closed Rickart modules. A necessary and sufficient condition is provided to ensure that this property is preserved under direct sums. Several connections between closed Rickart modules and other classes of modules are given. It is shown that every closed Rickart module is -nonsingular module. Examples which delineate this concept and some results are provided.

View Publication Preview PDF
Publication Date
Tue Mar 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Notes on Weibull Distribution
...Show More Authors

Weibull Distribution is one of most important distribution and it is mainly used in reliability and in distribution of life time. The study handled two parameter and three-parameter Weibull Distribution in addition to five –parameter Bi-Weibull distribution. The latter being very new and was not mentioned before in many of the previous references. This distribution depends on both the two parameter and the three –parameter Weibull distributions by using the scale parameter (α) and the shape parameter (b) in the first and adding the location parameter (g)to the second and then joining them together to produce a distribution with five parameters.

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Apr 04 2016
Journal Name
Journal Of Advances In Mathematics
ON CJ-TOPLOGICAL SPACES
...Show More Authors

Publication Date
Mon Aug 26 2019
Journal Name
Iraqi Journal Of Science
On Weakly Second Submodules
...Show More Authors

    Let  be a non-zero right module over a ring  with identity. The weakly second submodules is studied in this paper. A non-zero submodule  of   is weakly second Submodule when  ,  where ,  and  is a submodule of  implies either  or   . Some connections between these modules and other related modules are investigated and number of conclusions  and characterizations are gained.

View Publication Preview PDF
Scopus Crossref
Publication Date
Thu Apr 13 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On bg**- Connected Spaces
...Show More Authors

  In this paper, we define the bg**-connected space and study the relation between this space and other kinds of connected spaces .Also we study some types of continuous functions and study the relation among (connected space, b-connected space,  bg-connected  space and bg**-connected space) under these types of continuous functions.  

View Publication Preview PDF
Publication Date
Sun Apr 30 2023
Journal Name
Iraqi Journal Of Science
On Goldie lifting modules
...Show More Authors

On Goldie lifting modules

View Publication Preview PDF