Wall nucleation research has mainly focused on natural surface nucleation sites whose geometry is unknown and the effects of nucleation cavity geometry and size on flow boiling are not clear. The current research studies the effect of a blind hole with diameter 200 μm and depth 1 mm on bubble nucleation in a channel with water flow boiling. The boundary conditions were constant heat flux of 18.8 kW/m2, wall superheat of 8.7°C, water inlet temperature of 93.8°C and uniform velocity profile of 0.21 m/s at the inlet of
the channel with cross-section of 30 mm x 10 mm, leading to a Reynolds number of 10038. High-speed imaging of the bubble behavior allowed the measurement of the bubble temporal and spatial evolution and quantified the bubble growth period and waiting period between departure and new growth and associated fluctuations. The bubble growth period reaches up to 40 seconds with a corresponding waiting time of 0.9 ms. It is observed that a wave front is induced by the breakage of the bubble neck which propagates through the bubble, resulting in distortions that serve as initial trigger of bubble movement along the nucleation wall.