抄録
Three-dimensional laminar-flow development in a curved pipe has been investigated by using flow visualization technics. The hydrogen bubble and the powder of pumice used in Japanese painting were applied to traice the main and secondary flows, respectively. The thermal and refraction compensators were found to be needed for improved results. The results are obtained for the locations at 0°, 22.5°, 45°, 90°and 180° from the beginning of the curved pipe led by a long leading straight pipe under the flow conditions of Reynolds number 1000, Dean number 333 and the curvature ratio to be of 1/9.
As a result, the overshooting phenomenon of the main flow distortion towards the outer wall due to the centrifugal force in the midst of the development is clearly identified and an overall comparison is made with the available theoretical results in good agreement.
