MASS EXCHANGE AND FLOW PROPERTIES IN AND AROUND PERMEABLE SIDE-CAVITY OPEN-CHANNEL FLOW

Abstract

Measurements of instantaneous flow fields and the dye concentration in and around side cavity that was set around the permeable wall, were conducted. Measurements of flow properties were conducted by PIV. On the other hand, DV-camera was used for measurements of dye concentration. Permeable flow from the side wall of the side cavity was divided into 4 kinds of patterns. From the upstream wall, side wall, downstream or upstream and side wall. The permeable flow rate was set to 3 patterns. The 3%, 5% and 8% of the main-channel flow rate were changed. The aspect ratio (the streamwise length of the side cavity/the lateral length of the side cavity) was set to 2.
Flow patterns were changed. In the case of the permeable flow from upstream wall, side wall and upstrea and side wall, the center point of circulation flow moved to the downstream. On the other hand, in the caseof permeable flow from the downstream wall, the center point changed to the upstream. Dye concentration distribution in all cases was that high concentration area was observed at the upstream in the side cavity.In and around the circulation flow, there was low concentration. In the case of permeable flow from the upstream and side wall, the influences on flow fields or concentration fields were the greatest.