The present study involves experimental analysis of the modified Closed Wet Cooling Tower (CWCT) based on first and second law of thermodynamics, to gain a deeper knowledge in this important field of engineering in Iraq. For this purpose, a prototype of CWCT optimized by added packing under a heat exchanger was designed, manufactured and tested for cooling capacity of 9 kW. Experiments are conducted to explore the effects of various operational and conformational parameters on the towers thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of air measured at intermediate points of the heat exchanger and packing. Exergy of water and air were calculated by applying the exergy destruction method on the cooling tower. Experimental results showed a significant performance improvement when using packing on the CWCT. It can be observed that the thermal efficiency for the CWCT with packing under a heat exchanger and CWCT with packing above the heat exchanger are approximately 40% and 25% higher than that of the CWCT without packing respectively. As another part of the experiment results, it is indicated that the exergy destruction is directly proportional to air flow rate, cooling water flow rate, inlet cooling water flow rate and inlet Air Wet Bulb Temperature (AWBT) whereas, it is inversely proportional with spray water flow rate. In comparison with the cooling capacity of the tower, it was found that the exergy destruction approximately less than 20%. Exergy efficiency behavior is inversely proportional with the behavior of the exergy destruction. Empirical correlations are obtained to predict water film heat transfer coefficient and air-water mass transfer coefficient considering the influences of operational parameters.
Performance measures are a central component of management control system, making good planning and control decisions requires information about how different subunits of organizations have performed. To be effective, performance measures (both financial and nonfinancial) must also motivate managers and employees at all levels of organization to strive to achieve organization goals.
To give aclear picture about performance must be used compound measure, that was best than single measure.
Altman model can be used as a compound performance measure that measures the performance by tied a sum of variables, due to make weight for every variable to reach for performance.
מחקר זה בוחן את התפתחות הדימוי של ערבים בספרות הישראלית דרך עבודותיהם של אלי עמיר ודורית רביניאן שני סופרים חשובים שסיפוריהם מאתגרים סטריאוטיפים שוררים ומרחיבים את ההבנה התרבותית הניתוח הממוקם במסגרת הספרות המזרחית עוקב אחר האופן שבו דמויות ערביות עוברות מדמויות שוליים לאנשים מורכבים ומעודנים המשקפים שינויים סוציו פוליטיים רחבים יותר על ידי השוואת חקר הזהות והעקירה של עמיר בסביבה היהודית בבגדד לבין
The research aims at the following:
- Identifying the level of internal quantity efficiency in Medical colleges, University of Baghdad by determining the level of productivity for one group for the total batch according to sex variable (males and females). Procedures of the study
The researcher used the descriptive and analytical method has been used by following them up enhanced by flow indicators of students for one session depending on special statistical data analyss .
The results are as follows:
- The Faculty of Medicine were higher productivity scholarships for one year and two years of schooling, as well as the highest in the efficiency of the Faculty o
... Show MoreThe effect of linear thermal stratification in stable stationary ambient fluid on free convective flow of a viscous incompressible fluid along a plane wall is numerically investigated in the present work. The governing equations of continuity, momentum and energy are solved numerically using finite difference method with Alternating Direct implicit Scheme. The velocity, temperature distributions
and the Nusselt number are discussed numerically for various values of physical parameters and presented through graphs. ANSYS program also used to solve the problem. The results show that the effect of stratification parameter is marginalized with the increase in Prandtl number, and the increase in Grashof number does not practically vary the
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The current research aims to reveal the level of satisfaction of the mentors with the evaluation of their performance according to gender (male - female) and to formulate the predictive equation for the level of performance (dependent variable) from knowing the level of satisfaction with the evaluation (independent variable). (16 paragraphs) contains alternatives to the answer that measures the level of satisfaction (weak, medium, and high) (1,2,3), that is, with a hypothetical average of (32). It consisted of 100 educational counselors consisting of 45 males and 55 females, the results of the research concluded that the level of satisfaction with performance is below the mean when compared with the hypothetical average of the scale of s
... Show MoreThe reclamation of makeup water is studied in terms of breakthrough time (i.e., the leakage of the cations). Makeup water was subjected to lab-scale ion exchangers of two types: strong acid cation and weak base anion exchanger. The experimental investigation was directed to study the ion exchanger performance in terms of four different parameters (i.e., copper concentration, total dissolved solids (TDS), feed rate and bed depth). Box-Wilson composite rotatable design was adopted in designing the experiments. Breakthrough times of the effluent stream are measured in terms of copper concentration of 2 to 25 ppm, TDS concentration of 250 to 1250 ppm, feed rate of 0.38 to 5.34 l/h and bed depth of 5 to 70 cm. Simulation the effect of the stu
... Show Moreي لا ماق ثحبلا فادهأ قيقحتلو ثحبلا ةنيعل نايبتسا ءارجاو فراصملل ةيلاملا مئاوقلا ليلحتب ثحاب اهمهأ ناك تاجاتنتسا ىلإ ثحابلا لصوت دقو لإ صاخ معد دوجو مدع نم ةيفرصملا رطاخملا ةراد ةروصب اهدوجو مدعو فراصملل ةماعلا تارادلاا يف اهدوجو رصتقي ثيح ،ايلعلا تاهجلا لبق نم ديزي امم ،عورفلا يف ةلاعف مدع ةجيتن عورفلا نم ةدلوتملاو فراصملا اههجاوت يتلا رطاخملا اهمهأ ناك تايصوت ىلإ ثحابلا لصوت دقو امك ،ةيفرصملا تلاماعم
... Show Moreتضمن البحث التعريف بالإمام البزازي، وحياته العلمية، ومشايخه، وتلامذته، ومؤلفاته، ووفاته، وأربعة مسائل مختارة من ترجيحاته في الحدود والجنايات، والإمام محمد بن محمد بن شهاب بن يوسف (ت827هـ)، يُكنَّى بالكَردَرِيِّ الحنفي الخوارزمي الشهير بالبزَّازي، ويُنسب إلى كَرْدَر، وقد عرض في كتابه كثيرًا من كتب الحنفية، وذكر الكثير من آراء علمائهم مع تعرضه لبعض آراء المذاهب الأخرى. ولم يعتمد على التعريفات اللغوية والاصط
... Show MoreResearch is aimed at defining the risks that the sales activity of the General Company for Leather Industries about a special, then diagnose these risks, through a set of indicators, which indicate its existence and try to overcome them, and minimizing the negative effects on those activities.
The research found some conclusions, which emphasizes that the General Company for Leather Industries, suffer from a lack of profit, and a large decrease in sales; a result of absence of demand on its products and rising cost of the expenses to income ratio of, which was reflected in the cost per unit produced. Also the conclusions shown that the number of sales outlets for the company to cover the geographical area is not enough, in spite
... Show Moreدراسة في رواية سعودية