In this proposed effort, GTL has identified two methods for reducing chill-down time. In recent studies it has been shown that the production of super-hydrophilic surfaces can reduce chill-down time by altering the multi-phase boiling at the wall surface. The first method addresses this directly by altering the surface of stainless steel directly. The second method leverages GTL advanced cryogenic composites experience to produce a transfer line that further reduces chill-down time while also reduce the total thermal mass (and mass) of the system. Samples of both methods will be produced, and cryogenic testing will be performed on the samples in the phase I effort. This will provide a strong basis for the phase II effort where LOX and LCH4 testing can occur using existing facilities.
Reduced boil-off and low thermal inertia cryo-lines are useful in a variety of NASA applications. Many of NASA systems rely on cryogens, and future lunar activities require the transfer, storage and production of cryogens. These technologies are also useful to test facilities, launch vehicles and aircraft systems. Reduced thermal inertia and mass of cryogenic fluid lines is a benefit to nearly all propulsion systems.
Many of the commercial applications that apply to NASA also apply to the DoD, reduced boil-off, chill-down time and reduced mass are all beneficial to satellite systems and launch vehicles. Cryogenic fluid transfer is used in medical fields for MRI machines. Increased heat transfer on a surface is applicable to many systems, such as heat exchangers.