jikkennsouti.GIF (3348 ???) Visualization and WKB analysis of the internal gravity wave in the QBO experiment ???? ????-??????

The tank  is a doughnut-like cylindrical tank with an inner diameter of 180 mm and an outer diameter of 295 mm. It is filled with stable stratified water to about 500-mm depth to represent the tropical stratosphere. The wave in the real atmosphere occurs at the tropopause and propagates upwards. But, in this experiment, considering the symmetry of the internal gravity wave, the wave is generated in the upper part to facilitate the procedure.

The doughnut-like cover partitioned into 16 rooms is placed on the tank. Figure 1 is a side view of the apparatus. A thin rubber membrane is on the bottom of the cover. By pumping air in and out of the cover, the membrane moves upward and downward, generating waves. Air is pumped with a piston controlled by a stepping motor. The piston is moved sinusoidal to prevent the induction of high harmonic waves.


souti22s.gif (2762 ???)

Figure1 Side view of apparatus