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طلب مساعده لو تكرمتو

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  1. [1]
    الملك المجهول
    الملك المجهول غير متواجد حالياً

    جديد

    تاريخ التسجيل: May 2007
    المشاركات: 2
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    طلب مساعده لو تكرمتو

    إخواني الكرام
    بس إذا ممكن إفادتي في
    أنني إريد قانون كيفية حساب كفاءة المكيف بالإشتقاق إذا ممكن

    من مواضيع الملك المجهول :


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  2. [2]
    FAYEZ GHABBOON
    FAYEZ GHABBOON غير متواجد حالياً
    عضو


    تاريخ التسجيل: May 2007
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    Cop = Energy Sought / Enrgy That Cost
    Kw/kw
    Enrgy Sought Means The Cooling Or Heating
    Energy That Cost Means The Electrical Power Consumption
    .......no Derivation , This Is By Definition
    And Both Items Are Catalouged Data Generated By Labs

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  3. [3]
    RAMI GHANEM
    RAMI GHANEM غير متواجد حالياً
    عضو فعال
    الصورة الرمزية RAMI GHANEM


    تاريخ التسجيل: Dec 2006
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    Lightbulb

    The efficiency of chillers depends on the energy consumed. Absorption chillers are rated in fuel consumption per ton cooling. Electric motor driven chillers are rated in kilowatts per ton cooling.
    KW/ton=12 / EERKW/ton=12 / (COP x 3.412)COP=EER / 3.412COP=12 / (KW/ton) / 3.412EER=12 / KW/tonEER=COP x 3.412
    If a chillers efficiency is rated at 1 KW/ton, the COP=3.5 and the EER=12
    Cooling Load in - kW/ton

    The term kW/ton is common used for large commercial and industrial air-conditioning, heat pump and refrigeration systems.
    The term is defined as the ratio of the rate of energy consumption in kW to the rate of heat removal in tons at the rated condition. The lower the kW/ton the more efficient the system.
    kW/ton = Pc / Er (1)
    where
    Pc = energy consumption (kW)
    Er = heat removed (ton)
    Coefficient of Performance - COP

    The Coefficient of Performance - COP - is the basic unit less parameter used to report the efficiency of refrigerant based systems.
    The Coefficient of Performance - COP - is the ratio between useful energy acquired and energy applied and can be expressed as:
    COP = Eu / Ea (2)
    where
    COP = coefficient of performance
    Eu = useful energy acquired (btu in imperial units)
    Ea = energy applied (btu in imperial units)
    COP can be used to define both cooling efficiency or heating efficiency as for a heat pump.
    • For cooling, COP is defined as the ratio of the rate of heat removal to the rate of energy input to the compressor.
    • For heating, COP is defined as the ratio of rate of heat delivered to the rate of energy input to the compressor.
    COP can be used to define the efficiency at a single standard or non-standard rated condition or a weighted average seasonal condition. The term may or may not include the energy consumption of auxiliary systems such as indoor or outdoor fans, chilled water pumps, or cooling tower systems. For purposes of comparison, the higher the COP the more efficient the system.
    COP can be treated as an efficiency where COP of 2.00 = 200% efficient For unitary heat pumps, ratings at two standard outdoor temperatures of 47oF and 17oF (8.3oC and -8.3oC) are typically used.
    Energy Efficiency Ratio - EER

    The Energy Efficiency Ratio - EER - is a term generally used to define the cooling efficiency of unitary air-conditioning and heat pump systems.
    The efficiency is determined at a single rated condition specified by the appropriate equipment standard and is defined as the ratio of net cooling capacity - or heat removed in Btu/h - to the total input rate of electric energy applied - in watt hour. The units of EER are Btu/w.h.
    EER = Ec / Pa (3)
    where
    EER = energy efficient ratio (Btu/W.h)
    Ec = net cooling capacity (Btu/h)
    Pa = applied energy (Watts)
    This efficiency term typically includes the energy requirement of auxiliary systems such as the indoor and outdoor fans and the higher the EER the more efficient is the system.

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  4. [4]
    الملك المجهول
    الملك المجهول غير متواجد حالياً
    جديد


    تاريخ التسجيل: May 2007
    المشاركات: 2
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    إذا ممكن يأخوان بالعربي

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