Fatemeh Najafian - Student at Institute of Geophysics, Tehran University, Tehran, Iran
Abbasali Aliakbari Bidokhti - Professor at Institute of Geophysics, Tehran University, Tehran, Iran
Asghar Bohluly - Professor Assistant at Institute of Geophysics, Tehran University, Tehran, Iran

Because of their consistent direction, density (gravity) currents are important in the distribution and removal of pollutants from the semi-enclosed seas such as the PersianGulf. The extent of which a gravity current is diluted, through mixing of the current with surrounding ambient fluid, is of particular interest in ocean currents polluted byindustrial effluents or pollutants. Such mixing also affects the dynamics of gravity currents propagating through the reduction of the density difference that drives the current.[1] The ultimate properties of the deep or intermediate waters are also determined not only by the direct processes of air-sea interaction that creates the initial overflowingwater, but also by the mixing due to entrainment of surrounding fluid during the density current’s descent [2, 3, 4]. The aim of the present study is to present a flowmodel for the gravity current exiting the Persian Gulf. In this model entrainment process is also included.