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.
الامن الجماعي في اسيا .. بقلم : لونيك فرو وار
يهدف هذا البحث الموسوم بـ (المنهج النقدي في كتاب الرجال للنجاشي(ت 450هـ )إلى تسليط الضوء على حياة النجاشي ومكانته العلمية والكشف عن منهجه النقدي في كتابه المذكور.
This research deals with the idea of how the poetic reading can be a
rich field for producing the potential meanings in each text, through observing
the connection of the words and their link with other, thus composes, from the
collection of these interlaced meanings, what is called the poetic significant
(Symbolic) elaboration which deals with the reader of the text by regarding
him as a producer not as a consumer who can read a conscious reading, and
be diligent to solve the problem of the links of the relations among the
inspiring words because the language of poetry is an inspired language which
is capable of diversity and multiplicity of readings which is called the Symbolic
elaboration.
تمت دراسة سرعة الاخلاف في النوع Branchiura sowerbyi وعلاقتها بدرجات الحرارة حيث لوحظ ان قابلية هذه الديدان على اخلاف الحلقات الجسمية التي تحوي على الخيوط الغلصمية تكون اسرع من قابليتها على اخلاف الحلقات الجسمية الاخرى وبنسبة موت اقل خاصة في درجة حرارة ( 20 ± 3 ) م°.
واقع ومستقبل الصراعات الدولية والاقليمية في البحر الاحمر
It has become the subject of the environment and its problems during the last three decades of the important topics and dangerous that gained the attention of researchers in this regard as especially with the worsening repercussions severe, and turned out to be hot issues impose themselves urgently everywhere in the world, not concerned with the environment and specialists out, but also on all people wherever they are, regardless of their standard of living, and the circumstances of their lives, and their level of education and culture because the relationship of man with environment relationship since antiquity as relied upon to provide what they need him to stay, and through the stages of the development of civilization has made some a
... Show Moreمن المتفق عليه أن هناك طريقا واحدا لنشر الثقافة والقضاء على الجهل هو التعليم .ولعل أبرز ماشهدته مدينة بغداد من تطور هو ظهور المدر سة ومن ثم إنتشارها بشكل كبير وفق المفهوم الحديث مما أثرفي عموم الحياة اليومية ، ومن ضمنها التعليم العالي .إن الإستقرار من أهم ماتحتاجه الجامعة للقيام بواجباتها ولايأتي الإستقرار إلا بالإستقرار الذي يضمن لنا أن تكون الجامعة بعيدة عن ما قد يستجد من الأهواء و النزاعات.
The Spanish King Alfonso X could deliver mane Andalusia culture to Europe, but it is the subject of our research, we decided to give a brief overview of his life.
This king March was politically different from the rest of the Spanish kings, which is opening up to the literature and Eastern thought, it is the.
السياسة في الفلسفة الاسلامية : الفكر السياسي عند الفارابي