The wettability of liquid film flowing on an inclined plate is extremely deteriorated if there is a vertical wall on the channel side. In this study, an experimental study was conducted to investigate the influence of the side wall on the dryout of liquid film flow. The film surface forms a meniscus having a minimum film thickness near the side wall. The thin film thickness causes the dryout of film flow at lower flow rate. To avoid the appearance of the minimum thickness, the test channels of SUS-304 plate having circular side walls with various curvature radii RS were manufactured and the surface profiles of liquid film were measured experimentally for three kinds of test liquids. The meniscus profile was flattened at appropriate radius of curvature, i.e., RS.~6 mm for θR=20～30°(θR : receding contact angle) in this experiment. The critical Weber number at which dryout disappears is lowered remarkably and is recovered to the value those experienced for the flat plate without side walls.
