For the flow between rotating shaft and padded cylinder like a partial arc journal bearing, the critical Taylor numbers based on the pad clearance and cavity clearance were evaluated with changing cavity arc extent. Three types of phenomena have been found. In the first type, the Taylor vortices based on the cavity clearance were held throughout both regions of cavity and pad clearances. In the second type, the vortices based on the cavity clearance changed into those based on the pad clearance when they passed through the pad clearance, and downstream they returned to their former state. In the third type, the vortices based on the pad clearance were held throughout both regions.
For the flow field perpendicular to the axis, the velocity vectors were measured by PIV to discuss the three-dimensional construction of the flow near the pad.

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Flow visualization around the airfoil models consisting of flat panels was performed in a smoke wind tunnel. One is a basic airfoil of a double wedge, and the other is a modified double wedge airfoil model. The Reynolds number based on the airfoil chord length was about 2.8 × 10⁵. The lift coefficients were calculated by using the modified Yamana's method which was based on the potential flow. The results of the flow visualizations show that the streamlines around the modified double wedge airfoil model are similar to the basic double wedge one in the small angle of attack range from α = 0° to α = 8°. And it is also shown that the maximum lift coefficient of the modified double wedge airfoil model is a little higher than that of the basic double wedge one.

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