| 摘要 |
PURPOSE:To measure a three-dimenional shape of a cavity simply, easily and accurately, by providing on the surface of an object to be inspected, projecting pins for measurement having a plurality of marks in parallel at appropriate intervals on the side surface. CONSTITUTION:1a-1d indicate propeller blades of a propeller 1; 2 is a propeller boss; 3 for cavities generated on the respective propeller blades; 5 for a cavitation tunnel body; 6a-6d for windows for observation; 7a-7c for a plurality of measuring pins, which are projectingly disposed at the locations at distances different respectively from the front edges 10a-10c but on the same radius with respect to the propeller blades 1a-1c, while the cross-section of the pins form stream line against the water stream, on the side surface of which parallel stripes are painted with different colors from their bottom ends; and lastly 9a, 9b represent strobe lights. Flickering of the strobe lights 9a, 9b is performed with changes of their phase, and the propeller blades 1a-1d are observed successively. Further, when colors on the side surface of the pins 7 for measuring the cavities, located within the cavities 3 are compared with the surfaces of the cavities 3, said surfaces can be observed obviously. |
