Sökning: "zeotropic"

Hittade 5 avhandlingar innehållade ordet zeotropic.

  1. 1. Mixture Effects in Shell-and-Tube Condensers. Theory and Calculations

    Författare :Tord Karlsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; shell-and-tube; heat transfer; zeotropic; condensation; mass transfer; mixture;

    Sammanfattning : Zeotropic mixtures have come into more frequent use as working fluids (refrigerants) in heat pumps and air conditioning equipment due to the phase-out of ozone-depleting substances. Substantial drop in performance for shell-side condensation in shell-and-tube condensers when replacing a pure fluid with a mixture has been reported in the literature. LÄS MER

  3. 2. Condensation of Zeotropic Refrigerant Mixtures in Shell-and-Tube Condensers

    Författare :Dave Sajjan; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : .... LÄS MER

  4. 3. Flow Boiling Heat Transfer and Pressure Drop. Experiments and Model Development for Complex Geometries

    Författare :Sven Wellsandt; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; pressure drop; zeotropic mixtures; heat transfer; herringbone microfin; dimple plate; modelling; evaporation; flow boiling; experiments;

    Sammanfattning : Two very different evaporator geometries, a dimple plate and a herringbone microfin tube, have been studied. Heat transfer and pressure drop for both pure refrigerants and refrigerant mixtures have been determined experimentally. LÄS MER

  5. 4. HFC Mixtures as Replacement for HCFC-22 in Large-Scale Heat Pumps and Chillers

    Författare :Cecilia Gabrielii; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; R404A; R143a; R125; performance; R134a; R32; replacement; zeotropic HFC mixtures; simulations; design; measurements; chiller; R407C; condenser evaporator; screening; optimization; heat pump; R22;

    Sammanfattning : Replacement of the conventional refrigerant HCFC-22 (R22) is one of the urgent issues to be solved within the scheduled time-frame of the international regulation of the HCFCs. Since there exists no pure fluid that can replace R22 in the same general way as HFC-134a (R134a) is a replacement for CFC-12, HFC mixtures are suggested as possible substitutes. LÄS MER

  7. 5. Phase-out of refrigerant R22

    Författare :Anders Johansson; KTH; []
    Nyckelord :Retrofit; Phase-out; CFC; HCFC; HFC; R22; R407C; R417A; R404A; R134a; Ozone depletion; Zeotropic refrigerant mixture; Circulated composition; Measurement; Energy; Energy efficiency; System; Systems analysis; Modelling; Simulation; Prediction;

    Sammanfattning : .... LÄS MER