A vertical two-dimensional turbulence numerical model for the interaction of waves and currents is developed in the paper based on the nonlinear two-equation k - ε model with the VOF method. The one-dimensional equivalent advection velocity and equivalent mixing coefficient are defined and the solving process is introduced： The pollutant concentration field, generated by an instant source in waves and currents, is calculated with the model, and then the equivalent advection velocity and equivalent mixing coefficient are obtained by calculating the time derivative of the mean and variance of pollutant concentration probability distribution. The effects of wave period and wave height on the equivalent mixing coefficient for waves and wave-currents are also investigated.
