In this paper, experimental investigation on spray atomization and droplet dynamics inside a thermostatic expansion valve (TXV), a component commonly used in vehicle refrigeration system, was conducted. A needle and an orifice were copied from a commercial TXV and machined to be mounted inside a chamber with optical access so that the flow inside the TXV is simulated and visualized at the same time. The break-up and atomization of the refrigerant were documented near the downstream of the orifice under different feed conditions for two TXV with different geometry. A Phase Doppler Anemometry (PDA) system was used later to measure the size and velocity of atomized refrigerant droplets. The results showed that the droplet size variation along the radial direction is slightly decreased at near downstream and increased at farther downstream due to the coalescence. The increase of the pressure drop through throttling induces more droplets splashed from the needle plate and more violent secondary breakup at the downstream for TXV 1, which is featured by wide expansion space between the needle and orifice. Such trend is less apparent on TXV 2, of which the expansion space is much narrower. Further study of the impingement effect indicate that a more active coalescence of incoming droplets and ejected droplets is taking place in TXV2, which potentially offset the effect of the secondary breakup induced by the impingement. This makes TXV2 operating more stable and less likely to be subjected to the hunting.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Experimental Investigation of Droplet Dynamics and Spray Atomization inside Thermostatic Expansion Valves


    Additional title:

    Sae Int. J. Mater. Manuf
    Sae International Journal of Materials and Manufacturing


    Contributors:
    Lee, Chia-Fon (author) / Huo, MIng (author)

    Conference:

    SAE 2011 World Congress & Exhibition ; 2011



    Publication date :

    2011-04-12


    Size :

    9 pages




    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Experimental investigation of droplet dynamics and spray atomization inside thermodynamic expansion valves

    Huo,M. / Lee,C.F. / Univ.of Illinois at Urbana-Champaign,US et al. | Automotive engineering | 2011


    An Experimental Investigation of Hypersonic Shock-Droplet Atomization

    Schroeder, Steven A. / Moran, Miguel / Salauddin, Sheikh et al. | AIAA | 2024



    An Improved Numerical Model for Thermostatic Expansion Valves Used in Automotive Air-Conditioning Systems

    Monforte, R. / Society of Automotive Engineers | British Library Conference Proceedings | 2003