PGBA, a 0.08m2 / 27 liter spaceflight plant chamber payload employs two temperature-controlled liquid coolant loops to control the temperature and humidity of the sealed plant chamber independently. Cabin-air cooled thermoelectric heat pumps control the temperature of the water-alcohol coolant fluid in each loop, which is circulated by small, low-power, magnetically-coupled positive displacement gear pumps, designed to meet NASA safety requirements. Pulse-width-modulated DC current control circuits, controlled by two PI software controllers, maintain temperature and humidity accurately. The coolant loops feature bellows-based expansion vessels to accommodate thermal expansion and pressure fluctuations. Pressure sensors monitor the proper function and performance of the system. Pressure decay tests and unique fill procedures should ensure leak and air bubble-free operation.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Thermal Design of a Spaceflight Plant Chamber Payload


    Additional title:

    Sae Technical Papers


    Contributors:

    Conference:

    International Conference On Environmental Systems ; 2003



    Publication date :

    2003-07-07




    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Spaceflight payload design flight experience G-408

    Durgin, William W. / Looft, Fred J. / Sacco, Albert, Jr. et al. | NTRS | 1992


    Spaceflight Payload Design Flight Experience G-408

    W. W. Durgin / F. J. Looft / A. Sacco et al. | NTIS | 1992


    Mass Transport in a Spaceflight Plant Growth Chamber

    Hoehn, A. / Heyenga, A. G. / Clawson, J. et al. | SAE Technical Papers | 1998