In the present paper, two retrofitted compact and high efficient microchannel heat exchangers were proposed. The microchannel evaporator consists of two rows of microchannel tubes and louvered fins. Although air side and refrigerant side pressure drop of the microchannel evaporator is slightly higher, its cooling capacity is higher than that of the baseline evaporator. The new SPF condenser is very similar to the normal PF condenser in structure but receiver-dryer is integrated in the condenser core before the last two refrigerant passes. The new microchannel heat exchangers have advantages in compactness (17.2% and 15.1% volume reduction for evaporator and condenser, respectively), weight (2.8% and 14.9% lighter for evaporator and condenser, respectively), and heat transfer characteristics compared with the currently used heat exchangers in mobile air conditioning (MAC) industry. The biggest benefit of the microchannel tube applied on evaporators is easy manufacturing to match variable performance requirements and to reduce the tooling investment. One enhanced and one baseline R134a MAC systems were established including the new microchannel heat exchangers and the traditional MAC heat exchangers, respectively. The system performances have been experimentally carried out under variable ambient conditions in psychrometric calorimeter test bench. The optimal system refrigerant charge amounts for both systems were tested and the minimum effective charge amount was less than that of the baseline system. The enhanced system could supply more cooling capacity to car compartment under all test conditions because of higher performance heat exchangers. The coefficient of performance (COP) of the enhanced system was slightly lower than that of the baseline system under idle conditions but higher under all the other test conditions. Cooling capacity and COP of the enhanced system was increased by about 5% and 8% under high vehicle speed condition. However, the new system should be optimized in several aspects such as refrigerant mass distribution in the microchannel evaporator, more efficient compressor, and system control.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Performance enhancement study of mobile air conditioning system using microchannel heat exchangers


    Additional title:

    Höhere Leistung einer Fahrzeugklimaanlage mit Mikrokanal-Wärmeaustauschern


    Contributors:
    Qi, Zhaogang (author) / Yu Zhao (author) / Chen, Jiangping (author)

    Published in:

    Publication date :

    2010


    Size :

    12 Seiten, 14 Bilder, 10 Tabellen, 19 Quellen




    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English




    Heat transfer enhancement in advanced automotive air-conditioning heat exchangers

    Lozza,G. / Univ.Pavia,IT | Automotive engineering | 1992


    AIR CONDITIONING SYSTEM HAVING CYLINDRICAL HEAT EXCHANGERS

    GILLEY ADAM / POWELL PATRICK / BIMA MIKE | European Patent Office | 2017

    Free access

    Air conditioning system having cylindrical heat exchangers

    GILLEY ADAM / POWELL PATRICK / BIMA MIKE | European Patent Office | 2018

    Free access

    High-performance heat exchangers for automotive heating and air conditioning systems

    Kern,J. / Sueddeutsche Kuehlerfabrik Behr,Stuttgart,DE | Automotive engineering | 1989