| 摘要 |
PROBLEM TO BE SOLVED: To provide a jetting nozzle capable of efficiently excavating and suppressing the increase of cost. SOLUTION: The jetting nozzle 1 is provided with a jetting nozzle main body 2 and a flow passage 3. The flow passage 3 is provided with an introducing part 4, a contraction flow part 5, a throttle part 6 and diffuser part 7, which are coaxially arranged. The introducing part 4 is a circular passage having the cross-sectional shape centering around the axis line P. The throttle part 6 minimizes the cross-seasonal area of the flow passage 3. The contraction flow part 5 is formed into a trumpet shape and connected to the introducing part 4 and the throttle part 6. The contraction flow part 5 is formed so that the radius of curvature R of the cross-section including the axial line P is larger than the width (d) of the throttle part 6. The diffuser part 7 is connected to the throttle part 6 and the width of the flow passage 3 is increased as the diffuser part 7 goes to the downstream side. The diffuser part 7 is formed so that the angleθformed by the wall surfaces 7a, 7b each other in the cross- section including the axial line P is <=15 deg. and the length L is formed enough to generate cavitation in the throttle part 6.
|
