抄録
The hydrodynamic structure of the high-speed water jet utilized in the jet grouting was experimentally investigated. The nozzle diameter of water jet ranged from 2 to 6mm, and the outlet pressure is up to 20 MPa, so the jet velocity reaches to several hundred meter per sec. The double-pulse Nd:YAG Laser and CCD camera with image intensifier were used to capture clear images of the water jet. From the captured images, velocity of water jet was measured using LIF technique combined with PTV at various locations from outlet of nozzle. The result showed the velocity of water jet remains its initial velocity at 400D (D: nozzle diameters) from nozzle outlet. Radial velocity profile inside the jet showed flat velocity profiles for pressures and locations from outlet in the present experiment.
