Investigation on Porous Materials for Cesium Beam Frequency Standard in Space Environment

Based on design principle of spill-resistant oven, the function characteristics of three kinds of porous materials were investigated in theory and experiment respectively, in order to suppress spilling of liquid cesium under simulated space environments. In detail, using capillary wetting theory in microgravity, it was analyzed that the anti-spill mechanism on how hydrophobic surface of stainless steel can avoid liquid cesium to spill from the orifice of heat oven. Meanwhile, the experiment of cesium absorption on graphite and simulation of random vibration for cesium oven were carried out, for the sake of the availability of cesium beam frequency standard in space environment. Furthermore, a new notional strategy which depends on extraordinary structure of porous wick with different zone-properties is able to trap the droplets under vibration conditions, and can provide one possibility for potential application in anti-spill technology of spaceborne atomic clocks.