The investigation of natural convection in an annular space between two concentric cylinders partially filled with metal foam is introduced numerically. The metal foam is inserted with a new suggested design that includes the distribution of metal foam in the annular space, not only in the redial direction, but also with the angular direction. Temperatures of inner and outer cylinders are maintained at constant value in which inner cylinder temperature is higher than the outer one. Naiver Stokes equation with Boussinesq approximation is used for fluid regime while Brinkman-Forchheimer Darcy model used for metal foam. In addition, the local thermal equilibrium condition in the energy equation of the porous media is presumed to be applicable for the present investigation. CFD ANSYS FLUENT software package (version 18.2) is used as a solver to this problem. Various parameters are examined; Rayleigh number, Darcy number, and thermal conductivity ratio to study the effect of them on fluid flow and heat transfer inside the annuli space in the suggested design of metal foam layer. current model is compared with the available published results and good agreement is noticed. Results showed that as Rayleigh number increases the dominated of convection mode increases and Nusselt increases. Also, Nusselt is larger at the higher Darcy and thermal conductivity ratio. It was found that at Rayleigh of 106 and thermal conductivity ratio of 104 Nusselt reach its higher value which is 6.69 for Darcy of 0.1 and 6.77 for Darcy of 0.001. A comparison between this design and the traditional design was established for Darcy 0.001 and thermal conductivity ratio 102, and its showed a good enhancement in Nusselt number and the greatest enhancement percentage was 44% at Rayleigh equal 5*104 while the lowest percentage is 6% for Rayleigh equal106.
Background: The aim of this study was to comparatively evaluate the push out bond strength (PBS) of root canal fillings using four different obturation techniques (single cone (SC), cold lateral compaction (CLC), continuous wave (CW), and carrier based gutta percha (CBG)). Materials and Methods: Forty mandibular premolar decoronated and instrumented with rotary ProTaper to F3 then teeth were divided randomly into 4 groups of 10 teeth for each as follow: group (I) single- cone obturation with matched-taper gutta-percha, group (II) cold lateral compaction technique, group (III) continuous wave of obturation technique, and group( IV) carrier based gutta-percha technique. Zinc oxide eugenol (ZOE) sealer was used as a root canal sealer for the
... Show MoreBackground: Helicobacter pylori are important gastrointestinal pathogen associated with gastritis, peptic ulcers, and an increased risk of gastric carcinoma. There are several popular methods for detection of H. pylori (invasive and non-invasive methods) each having its own advantages, disadvantages, and limitations, and by using PCR technique the ability to detect H. pylori in saliva samples offers a potential for an alternative test for detection of this microorganism. Materials and methods: The study sample consists of fifty participants of both genders, who undergo Oesophageo-gastrodudenoscopy at the Gastroenterology Department of Al-Kindy Teaching Hospital Baghdad/ Iraq, during five months period from January 2014 to May 2014. They we
... Show MoreForeign direct investment has seen increasing interest worldwide, especially in developing economies. However, statistics have shown that Yemen received fluctuating FDI inflows during the period under study. Against this background, this research seeks to determine the relationship and impact of interest rates on FDI flows. The study also found other determinants that greatly affected FDI inflows in Yemen for the period 1990-2018. Study data collected from the World Bank and International Monetary Fund databases. It also ensured that the time series were made balanced and interconnected, and then the Auto Regressive Distributed Lag method used in the analysis. The results showed that the interest rates and
... Show MoreThe research problem lay in the existing of this direct relation between the increasing and the big variety of the goods and the producing companies which mean the increase of the competition and the directing techniques of the commercial advertisings, which become spread everywhere and in an age characterized with the great varieties in the tests and the stances which requires the designers to seek designing accomplishments that are characterized with creativeness , seriousness and unsallity through the designer depending in constructing his / her texts and his/ her visual items on reference forms metaphors to achieve his / her designing purposes.
So the researcher through her primary flying study seek the identifying the manner of
The design of future will still be the most confusing and puzzling issue and misgivings that arouse worry and leading to the spirit of adventures to make progress and arrive at the ways of reviving, creativity and modernism. The idea of prevailing of a certain culture or certain product in design depends on the given and available techniques, due to the fact that the computer and their artistic techniques become very important and vital to reinforce the image in the design. Thus, it is very necessary to link between these techniques and suitable way to reform the mentality by which the design will be reformed, from what has been said, (there has no utilization for the whole modern and available graphic techniques in the design proce
... Show MoreAddresses current research to the subject of metaphor as a field important in the design of industrial product, so it was a problem search: Does industrial product which is designed mainly to reflect the principle of metaphor role in receiving, and how the application of mechanisms theory correct as stipulated in institutions metaphor properly for this orientation in achieving those metaphors. What are the relations of reciprocity that influenced the establishment of the design and construction of the system for industrial product, the objectives of the research were standing on the interactive nature of the relations between the metaphor and the process of industrial product design? And identify strengths and weaknesses in the processes
... Show MoreThe need for an intellectual understanding of the context from many aspects' dictates understanding the ways through which the graphic designer walks in simulating the intent of the design process and elevating it to levels of communicative perception that leads to communicating the idea to the recipient, and it is thus a need closely related to the context, if it is historical. Culturally or socially, and between the mechanisms of selecting and operating the elements and units of the graphic and design achievement. On this basis, the role of context in graphic design can be studied.
The research included four chapters, the first chapter of the research problem and the need for it, and the aim of the research was (discovering the
... Show MoreIf the Industrial Revolution has enabled the replacement of humans with machines, the digital revolution is moving towards replacing our brains with artificial intelligence, so it is necessary to consider how this radical transformation affects the graphic design ecosystem. Hence, the research problem emerged (what are the effects of artificial intelligence on graphic design) and the research aimed to know the capabilities and effects of artificial intelligence applications in graphic design, and the study dealt in its theoretical framework with two main axes, the first is the concept of artificial intelligence, and the second is artificial intelligence applications in graphic design. The descriptive approach adopted a method of content
... Show MoreIt is general known that any design in various fields such as the interior design in the field of spaces interior for the public and specific buildings that is concern about the use of humans resident , as well as other considerations relating to the organization of design elements and lines of locomotors activity and the validity of appropriate receiving to provide comfort and achieve the requirements of the position in the space of restaurants field of research.
The researcher choose the title of this study (processors design career in public spaces), the analytical study of the spaces of restaurants, as one of the public spaces that are running in their general environment of people in various strata , ages and other levels , whic
In the midst of conflicts different intellectual and knowledge of production processes and circulation we need constant search for different levels of Innovation replenished with renewed need to develop solutions to various problems. Amid this conflict comes to mind a question about what salt creative mechanisms act in Graphic Design? Through this research is marked (creative mechanisms act in Graphic Design) strive to find solutions
to this question, as well as cognitive it Sarphi side modern and developmental study to a broader understanding of the subject. And across four seasons, which included the first chapter of the research problem and the need for him, and then came the second chapter includes theoretical framework goal Bemb