Future space exploration programs require large quantities of both cryogenic and non-cryogenic fluids to accomplish missions. Large volume depot systems will be required to provide in-space supply to satisfy these mission requirments. Currently, passive liquid acquisition devices employing multiple channels are employed in space systems such as the shuttle to provide efficient vapor free liquid transfer. However, the increased size of the proposed depot tanks would require larger, more complex liquid accquisition systems. The proposed innovation would replace the multiple channel arrangement with a single circular fluid channel wound as a helix on the inner tank wall and directed to the tank outlet. After manufacturing of the acquisition cahnnel, it could be compressed similar to a spring to reduce its volume prior to installation in an inflatable or otherwise deployable depot tanks. A series of windows would be located at various points in the channel to allow liquid entry during transfer. The windows would employ fine mesh metal or synthetic screen material to provent vapor from entering the channel. A helical channel would assure efficient liquid acquisition from any area in the tank. POTENTIAL COMMERCIAL APPLICATIONS NASA, the DoD and the International Space community will benefit with the use of more efficient liquid acquisition from large propellant depots. Spring loaded helical channel liquid acquisition devices have the potential to enable inflatable cryogenic tanks for space and certain terrestrial applications. Batch processing of bulk materials that need to be dried, processed with inert gas or even gaseous acquisiton may be enhanced with this innovation
