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من يعرف topping cycle

  1. #1
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    من يعرف topping cycle

    السلام عليكم
    الاخوة الكرام ارجو ممن تتوفر لديه اي معلومات وابحاث عن topping cycle
    أن يزودنا بها
    وجزاكم الله خيرا


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  2. #2
    عضو

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    وين الردود

    السلام عليكم
    اخوتي الكرام اين ردودكم على الموضوع
    ارجو أن تساعدوني بأبحاث عن topping cycle
    وعقوبة لكم لأنكم تأخرتم بالرد
    أطلب أبحاث حول
    flow whith EULER EQUATION


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    من مواضيع ahmadnet :


  3. #3
    عضو

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    يا جماعة مشان الله ردو


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    من مواضيع ahmadnet :


  4. #4
    جديد

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    What is cogeneration? Cogeneration (also called Combined Heat and Power or CHP for short) is the generation of electricity plus the recovery of heat otherwise discharged to the environment. This heat is used for space heating of buildings, drying, to produce hot water or steam, or in various industrial processes. Commonly, electricity is generated at a central power plant, while on-site heating and cooling equipment is used to meet non-electric energy requirements. Today, cogeneration systems can achieve efficiencies over 80% while the separate systems have combined efficiencies of only 45% (1). How cogeneration works A typical cogeneration system consists of an engine, steam turbine, or combustion turbine that drives an electrical generator plus a waste heat exchanger to recover waste heat from the engine and/or exhaust gas to produce hot water or steam. Cogeneration produces a given amount of electric power and process heat with 10% to 30% less fuel than it takes to produce the electricity and process heat separately. In conventional power generation using heat engines, about two thirds of the energy input is lost as heat is rejected to the environment. CHP can recover the majority of this waste heat, creating a far better use of resources and cost savings, and resulting in energy savings of between 20 and 40%. If, for example, hot jacket water from an internal combustion engine such as a diesel-electric generator is passed through the hot side of a heat exchanger, the fluid on the other side can be heated and, in turn, used to provide space heating for a building. Not only does this recover a resource, but it also lessens parasitic power consumption by a radiator fan. Environmental benefits Because use of CHP can reduce total fossil fuel consumption, emissions to the atmosphere are reduced. It can result in reductions of up to 50% in CO2 emissions compared with conventional sources of heat and power as well as reduced emissions of sulphur dioxide and particulates (2). There are two main types of cogeneration concepts: ?Topping Cycle? plants, and ?Bottoming Cycle? plants. A topping cycle plant generates electricity or mechanical power first. Facilities that generate electrical power may produce the electricity for their own use, and then sell any excess power to a utility. A bottoming cycle plant generates heat first. Bottoming cycle plants are much less common than topping cycle plants. These plants exist in heavy industries such as glass or metals manufacturing where very high temperature furnaces are used. The four types of topping cycle cogeneration systems are: (1) An gas turbine or diesel engine producing electrical or mechanical power followed by a heat recovery boiler to create steam to drive a secondary steam turbine. This is called a combined-cycle topping system. (2) The second type of system burns fuel (any type) to produce high-pressure steam that then passes through a steam turbine to produce power with the exhaust provides low-pressure process steam. This is a steam-turbine topping system. (3) A third type employs hot water from an engine jacket cooling system flowing to a heat recovery boiler, where it is converted to process steam and hot water for space heating. (4) The fourth type is a gas-turbine topping system. A natural gas turbine drives a generator. The exhaust gas goes to a heat recovery boiler that makes process steam and process heat (3). Applications Approximately 56,000 (MW) of CHP electric generation is in operation in the United States and is widely used in the chemical, petroleum refining, and paper industries. More recently, light manufacturing industries, commercial buildings and universities have adopted this technology. In 1999, CHP plants accounted for 7% of U.S. electricity generation capacity and generated 9% of all electricity produced in the United States. A typical system efficiency was 68%. In Denmark and the Netherlands, more than 40% of electricity is obtained from CHP systems (4). In Alaska, over 50 villages capture waste heat from the jacket water of diesel electric generators to use for space heating. The University of Alaska Fairbanks condenses steam produced by the power plant to provide space heating for most of the campus. Golden Heart Utilities in Fairbanks sells steam from the power plant to selected users downtown for space heating.


    المصدر:http://www.uaf.edu/energyin/webpage/...generation.htm


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    من مواضيع مسلم 1403 :

    التعديل الأخير تم بواسطة motaz_95 ; 2006-07-08 الساعة 08:23 AM

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  6. #6
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    جزاك الله خيرا اخي الكريم
    أسأل الله أن يجمعني بك في الجنة


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  7. #7
    عضو

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    Topping cycle


    هو عبارة عن انتاج بخار الماء عالي الضغط و الحرارة والذي يستخدم بدوره في تشغيل التربينات المستخدمة في المولدات الكهربائية.... وبعد مروره بالتربين يتم استخدام الطاقة المتبقيه في تطبيقات اخرى كالتسخين



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  8. #8

  9. #9
    عضو فعال جداً

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    حضرتك يابشمهندس ممكن تلاقي البحث اللي انت عايزه بالبحث علي موضوع ال Cogeneration وستجد انه من انواعه ال Topping Cycle و ال Bottoming Cycle ...وفكرة ال Cogeneration بصفة عامة هو استخدام اطاقة المتمثلة في البخار الخارج من الغلايات لتوليد Power و Heat ..وال Power اما ان تحصل عليه بشكل ميكانيكي او بشكل كهرباء ..وال heat ممكن استخدامها في التسخين او حتي تبريد وتكييف " Absorption Cooling " ....والفرق بين ال Topping و ال Bottoming هو علي ماذا ستحصل في البداية اي علي ماذا تحتاج اكثر من الاخر Heat or Power ...يعني مثلا لو محطة كهرباء ستكون الاولوية لتوليد الكهرباء وبالتالي تذهب معظم طاقة البخار لتوليد الكهرباء ثم الجزء المتبقي يتم استخدامه لتطبيقات اخري وهذا النوع هو ال Topping cycle ..اما مثلا لو مصنع زجاج فأنت تحتاج ل Heat اكبر من ال Power ...لذا تستخدم اغلب الطاقة المتولدة لتوليد حرار للأفران والجزء المتبقي منها يذهب لتوليد الكهرباء ...ويكون هذا النوع هو ال Bottoming cycle ...ياريت اكون افدتك


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    التعديل الأخير تم بواسطة hazemhany ; 2012-01-07 الساعة 03:45 PM

  10. #10

الكلمات الدلالية لهذا الموضوع

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