Dynamic behavior of liquids in containers under low-gravity is discussed. Special emphasis is placed on the equivalent mechanical modeling for liquid sloshing and large motion during coasting and settling phases.
To investigate the interaction between the droplets in the spray combustion, microgravity experiments were performed. The experimental apparatus mainly consists of a combustion chamber, an 8 mm video camera and a 35 mm single-lens reflex camera. Fuel droplets of butanol or hexanol are arranged 2-dimensionally, representing the fuel droplet cloud in the splay. Electrically heated nichrome wires ignite the fuel samples simultaneously. The 35 mm camera observes the flame shape history. The effects of sample space on the flame shape are investigated . Main results obtained are in the followings: Because of the interaction between droplets, the unsteady combustion period. in which fuel vapor is accumulated around the droplets, becomes long . As the result, the steady state combustion is not observed in the combustion process and the flame size keeps increasing until it dis appears.
The diffusion coefficient of liquid lithium, which is expected to show large isotope effects because of its small atomic mass, was measured by the long capillary method under the microgravity due to the launch of the sixth TR-IA rocket. The detailed description is given for the procedure of the microgravity experiments for the very aggressive materials such as liquid lithium. The smaller diffusion coefficient was obtained for 7Li in liquid 6Li compared with the case of 6Li in liquid 7Li. These behaviors were discussed based on the theoretical calcula tions successfully in a qualitative manner from the point of view of the hard sphere model, in which the hard sphere diameter was determined from the theoretical point of view.