The article presents a two-dimensional numerical model for the injection of a fluid through a slot into a free stream. The model is based on a finite-volume integration of the equations governing mass, momentum, and heat transport. The solution accuracy was improved by using local grid refinement. The storage of variables was done in a collocated manner, thus allowing for the reduction of storage requirements and a more accurate interfacing of the various subdomains of the grid. The model developed was doubly validated by comparison with available experimental data and the results of an analytical method proposed for two-dimensional injection of an irrotational inviscid fluid.