Initial simulations of arrays of tidal turbines have been performed using FLUENT a computational fluid dynamics (CFD) package. The use of CFD allows analysis of several possible farm simulations with different boundary conditions. Details of these initial simulations have been published in:
Batten W.M.J. and Bahaj A.S. (2006) CFD simulation of a small farm of horizontal axis marine current turbines. Proceedings World Renewable Energy Congress (WREC-IX), Florence, 19-25 August 2006.

Predicted velocity field around 3 rows of marine current turbines

A typical simulation, using actuator disks is shown in figure on the right for 3 rows of turbines. The rows are of infinite width with the use of mirror boundaries. These results show that between the first row of turbines there is a region of flow acceleration akin to a venturi. This could mean that these turbines would produce more power.