2312 高耐圧可視化衝撃波管実験装置による高粘性流体の減圧相変化挙動に関する研究(S42-3 複雑流体の流動現象(3),S42 複雑流体の流動現象)  [in Japanese] 2312 Study of Phase Change Behavior of High Viscous Fluid under Sudden Decompression in a High Pressure Visualized Shock Tube experimental apparatus  [in Japanese]

The volcanic eruption occurs due to the sudden decompression of the high-pressure high-temperature high-viscosity magma. It is mainly depended on the appearance of the gas phase in the magma whether it is an explosive eruption or not. In the present study, the volcanic eruption is reproduced with the high-pressure visible shock tube apparatus and simulant materials. The simulant materials for the magma are two-fluid component of silicone oil as high viscosity fluid and acetone as volatile substance. In the experiment, the bubble forming behavior of the simulant materials and the rapid change in pressure is observed. Bubble forming behavior had completed in very short span and then bubbles developed. The number of bubbles that generated under sudden decompression increased as the initial pressure increased. It is indicated from the experimental results that the driving force of bubble forming under sudden decompression depends on the initial pressure.