The Capillary Flow Experiment-2 (CFE-2) consists of eleven fluid modules with unique geometries designed to test capillary flow in the microgravity environment. The first type of CFE-2 fluid module is the Interior Corner Flow (ICF) module, there are nine modules each with a different interior corner angle and geometry. The second type of CFE-2 fluid module is the Vane Gap (VG) module, there are two of these modules, each with a different cross section profile. The CFE-2 fluid modules are set up in the Maintenance Work Area (MWA) on board the International Space Station (ISS) and operated by an ISS crew member. The capillary flow data is in the format of video, and is recorded by the MWA camera and downlinked to the ground for data analysis.
July 2014 – The International Space Station commander Steve Swanson performed several bubble-free drain tests using the Interior Corner Flow 5 (ICF5) vessel on July 3, 2014. The ICF5 vessel has a square cross-section, and the top half of the test section is divided into 4 smaller square channels. There are 4 valves at the top of the test section corresponding to each of the 4 channels. During the runs, silicone oil was deployed into the test section to commence the top drain tests through one open valve. The silicone oil was drained from the test chamber through the open valve without ingesting gas into the reservoir. A top drain test with all the top valves open was then run. The Principal Investigator and his team at Portland State University are reviewing the test results.