Measuring and Numerical Simulation of the Free Water Surface of the Open Pump Suction

Detailed measurements of the free water surface of the open pump suction were obtained by PIV system. A step was arranged in the rectangular section of the model open type suction passage. The data have been measured with different conditions, such as the height of step (h_s), averaged velocity (v) near the entrance of the open type suction passage, and the water height (h) near the chest wall. The existence of the step influences the flow situation greatly, when h_s is higher, the flow situation becomes more turbulent. Near the end edge of the step, there were obvious drops of the water surface. When flow-velocity becomes bigger and water depth decreases, the flowing situations become more turbulent. Also, we calculated the free water surface at the open pump suction passage using the VOF method and the calculated results were coincided with the experimental data obtained under the same conditions. The results showed that the usefulness of PIV in obtaining the free water surface and validated the numerical model in simulation the open pump suction.