INFLUENCE OF INFLOW-OUTFLOW SYSTEMS FOR NATURAL MIXING IN A CIRCULAR TANK

A tank that is normally equipped with an inlet and outlet system would exhibit different response in the mechanics of inflows and outflows. This then allows natural mixing to take place. An effective natural mixing would then be defined when the natural flow processes taken place in the tank would somehow clean the storage water to the most optimum level. This paper presents the influence of inflow and outflow orientation in creating an effective natural mixing inside of a tank. The study involves the response of different inlet-outlet configuration systems in imitating natural cleaning. The cleaning herein is defined through mixing process taken place in the tank. A circular tank which may be translated as a retention pond in real life was filled with clay (kaolin), replicating a turbid storage. The cleanliness through mixing was measured by means of Total Suspended Solid (TSS) test. With this regards, nine different inflow-outflow orientations were tested. It was noticed that the lowest level of inflow (I3) and highest level of outflow (O1) gave the best results in producing effective natural mixing. On the other hand, poor mixing was noticed when the configuration of the inlet and outlet were kept in series.