In this work, an experimental study has been done to expect the heat characteristics and performance of the forced-convection from a heated horizontal rectangular fins array to air inside a rectangular cross-section duct. Three several configurations of rectangular fins array have been employed. One configuration without notches and perforations (solid) and two configurations with combination of rectangular-notches and circular-perforations for two various area removal percentages from fins namely 18% notches-9% perforations and 9% notches-18% perforations are utilized. The rectangular fins dimensions and fins number are kept constant. The fins array is heated electrically from the base plate with five different magnitudes of power-inputs. Five several air flow velocity into a duct are utilized. The influence of fin geometry, air flow velocity, Reynolds number and the surface heat flux on the heat-performance of forced heat convection have been simulated and studied experimentally. The experimental data indicates that the combination of 18% rectangular-notched and 9% circular-perforated rectangular fins array gave best forced heat performance in terms of average heat transfer coefficient about (25% - 45%) and (7% - 20%) compared than solid and 9% notches with18% perforations fins array respectively. Five empirical correlations to predict the average Nusselt number for the 18% notches with 9% perforations rectangular fins array at wide range of surface heat flux are deduced. The present data are compared with previous works and a good closeness in behavior is noticed.
Abstract
The objective of this research is to identify the analysis of the ethics of the administration in the development of the social responsibility of one government organizations, and to achieve the objectives of the research was the use of a questionnaire developed for the purpose of data collection and distribution to the research sample, was chosen as a total sample population (50) individuals were relying on statistical package to do a statistical analysis for this research, user, ANSI (SPSS) simple regression analysis, standard deviation, Pearson correlation coefficient.
Research findings show the role of social responsibility in achieving the university's strategy,
... Show MoreSecurity reflects a permanent and complex movement that complies with international and societal needs and developments in all its dimensions, interactions and levels. To constitute a universal demand for all States, communities and individuals. The question of security is one of the most important motivations and motivations that govern the behavior, and even the objectives of those societies and States. These groups or individuals have always sought to avoid fear and harm, and to provide stability, safety and security. In the light of this, security studies have been among the important fields of study in the field of international and strategic relations. The field witnessed many theoretical efforts, from the traditional perspective,
... Show MoreThe ultimate goal of any sale contract is to maximize the combined returns of the parties, knowing that these returns are not realized (in long-term contracts) except in the final stages of the contract. Therefore, this requires the parties to the contract to leave some elements open, including the price, because the adoption of a fixed price and inflexible will not be appropriate to meet their desires when contracting, especially with ignorance of matters beyond their will and may affect the market conditions, and the possibility of modifying the fixed price through The elimination is very limited, especially when the parties to the contract are equally in terms of economic strength. Hence, in order to respond to market uncertainties, the
... Show MoreThe aim of this study is to investigate the main causes of the family violence and its
social effects.
The study reveals that main factors causes of the violence are interaction between
multi-factors.
The study shows that the poverty, low educational level, house crowded, large family
size, all of these variables causes of the violence, and then causes of family disorganization
and juvenile delinquency.
The study contain of three sections:
First: Focused on the causes of the violence.
Second: The interaction between multi factors.
Third: Social effects of family violence.
Controls Scanning on the slippers a study fiqhiat Comparison
The subject of this research is an important topic, which is frequently repeated, and people need to know its wisdom, and has made it in front and the preface and three detectives, showed through discussion the meaning of the survey on the socks, its wisdom, its rules and conditions, and the duration of the survey on it, spoiled and reasoned and compared to the doctrinal doctrines, And the most correct statement of words I have concluded with a number of things, as follows:
- The need to ensure that the slippers are clean, visible and inwa
Contemporary life is racing against time in its temptations and variables, and it has become shaped and changed in an amazing way in its various aspects and fields. This was facilitated by intellectual and scientific communication between civilizations, and the rapid progression in successive inventions and discoveries in the fields of science and arts of knowledge. This contributed to a great economic and commercial renaissance. Then, these economic developments entered the world into a very strong competition, which forced producers to calculate all production costs, to reach the highest profits by reducing the price of the produced commodity on the one hand, and achieving quality in appearance (especially) on the other hand. Since the ma
... Show MoreThe tagged research problem (the outputs of the written text in conceptual art) dealt with a comparative analytical study in the concept of conceptual art trends (land art - body art - art - language).
The study consisted of four chapters. The first chapter dealt with the theoretical framework, which was represented in presenting (the research problem), which raised the following question: What is the role of the written text in the transformations of the conceptual arts?
The first chapter included (the importance of research) and (research objectives) seeking to conduct comparative research in the written text within the trends of conceptual art as a moving phenomenon in art, and to reveal the variable written text in the
... Show MoreDialogue is one of the most important means of calling to the Creator, as it is one of the scientific and verbal activities carried out by a group of interlocutors to present ideas they believe in, and evidence and proofs that express their views and demonstrate the reason for their belief in them, In order to arrive at the truth or a radical solution to a specific problem, so the interlocutor should pay attention to this science, study it and its etiquette, because the purposeful dialogue requires that the funniest of them be the most knowledgeable and knowledgeable about the axis of the hadith, and the funniest must also be able to be convinced of the rule of difference of opinion that does not spoil the issue of friendly They must also c
... Show MoreAbstract
All of us are indispensable for this rule (the most important and important) individuals, whether we were groups of leaders or followers of peoples or countries because the rule provides adequate guarantees for the correct positions and drawing the plan for successful decision-makers matching with the balances of Sharia without incompatibility between religious or worldly interests or legal positions and therefore in the framework of the most important appointment And distinguish it from the important from the interests or the appointment of the most important and distinguish from the important from the evils and through this rule we learn about the scientific and practical solutions t
... Show MoreLong memory analysis is one of the most active areas in econometrics and time series where various methods have been introduced to identify and estimate the long memory parameter in partially integrated time series. One of the most common models used to represent time series that have a long memory is the ARFIMA (Auto Regressive Fractional Integration Moving Average Model) which diffs are a fractional number called the fractional parameter. To analyze and determine the ARFIMA model, the fractal parameter must be estimated. There are many methods for fractional parameter estimation. In this research, the estimation methods were divided into indirect methods, where the Hurst parameter is estimated fir
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