FIELD MEASUREMENT AND NUMERICAL SIMULATION ON DEVELOPMENT AND MOVEMENT OF THE LOW OXYGEN WATER IN THE TONE RIVER BELOW THE ESTUARY BARRAGE

Field measurement and numerical simulation were carried out in order to investigate development and movement of the low oxygen water mass in the Tone River below the estuary barrage. The measurement data shows that low oxygen water frequently generated in the front part of salt wedge, and then developed downstream in the salt wedge gradually. Next, in order to simulate the characteristic behavior of the low oxygen water, the standard k-ε turbulence model is adopted in the numerical model of salt intrusion. Furthermore in addition to the k-ε model, DO-transport equation and BOD-transport equation are introduced for the purpose of simulating the characteristic behavior. Comparing the calculation results with the measurement data, the characteristic behavior are reappeared well.