Laboratory Measurement of Suspended Sediment Concentration by Using ADV

Abstract

When an Acoustic Doppler Velocimetry (ADV) is conducted to measure the flow velocities, it can record some information of particle concentration in signal amplitude. This phenomenon suggests that a new method to measure the suspended sediment concentration (SSC) by using ADV might come true. In this paper, the working principle of the ADV was analyzed, and then a series of experiments were carried out to clarify the relationship between the SSC and the signal amplitude. Experimental results show that when SSC is lower than 0.014 (ratio by volume), ADV can work effectively; meanwhile, SSC is a linear function of the signal amplitude. Based on experimental data, several linear formulas between SSC and the signal amplitude were established. In the formulas, the constant coefficients differ from each other for the various flow conditions, which may cause calculation errors. Accordingly, in order to improve the calculation precision, it is necessary to conduct additional experimental calibration. In this study, ADV is proposed to determine the SSC. In some experimental conditions of continuous and long-lasting SSC measuring, the method has great advantages and will be of great importance to study on the interaction mechanism between turbulence and sediment particles.