Investigation into peak attenuation of the inlet pollution at the outlet of a flume

With the increase of water resources pollution, as the main threat for the environment, many attempts have been undertaken to predict the concentration of pollutants through the numerical simulations or experimental studies. The main aim of this study was to estimate the concentration of the pollutant at different times and locations of a flume, particularly at the outlet, for different inlet concentration profiles. For this purpose, the one-dimensional advection-diffusion equation was used and discretized with finite difference method. Then, a number of codes were developed to solve the equation for different scenarios, in which the diffusion coefficient was assumed to be constant. The study was focused on a 10 m channel susceptible to entrance of the pollution with various profiles for a specific time. The magnitudes of inlet pollutants are different, but the peak magnitudes of inlet concentrations are the same. The numerical model results have shown a linear behavior for the relevant partial differential equation. Afterwards, in order to achieve an accurate solution for the numerical method, the appropriate time and distance steps were determined.