Boiling and condensing pumped loop microgravity experiment Available to Purchase

Aircraft testing of a boiling and condensing (two‐phase) pumped loop system was conducted to investigate transient induced by low gravity (Keplerian) maneuvers. The experiment, unchanged, will repeat a selected aircraft test sequence during its flight aboard a suborbital rocket. Such a test of a two‐phase system has never been done. A comparison of aircraft and rocket data, particularly equilibrium conditions, may validate aircraft testing of similar systems: Aircraft testing has been completed and preliminary results indicate that local transients induced by Keplerian maneuvers do not generate sizeable or lasting feedback. System feedback, expected to damp exponentially with loop transit time, θ_loop (20 s<θ_loop<30 s) is negligible compared to local temperature transients having shorter equilibrium times, θ_local (5<θ_local<10 s). Since θ_local is typically 2 to 5 times shorter than the duration of low gravity, t_0−g (20 s<t_0−g<25 s), equilibrium conditions are approximated. Transients following a transition from normal to low gravity resulted from destratification of hot and cold fluid, loss of the liquid convection component in laminar flows, and a reduction in condensing heat transfer.