A jet pump operates under the Venturi effect, where a fluid enters through a primary nozzle and, when passing through a convergent-divergent nozzle, it reaches supersonic conditions, originating a vacuum pressure in a secondary fluid. Fluid-dynamics simulations of jet pumps are performed here using standard k-e turbulence model. Numerical results are compared to those obtained with an analytical model previously developed, concluding that both approaches predict a similar behavior of Match number, fluid pressure and fluid velocity. A parametric study is done to determine the influence of inlet pressure and primary nozzle position in jet pump performance, Mach number field and total pressure profile. Both parameters have an important influence in those variables, but this is not monotonic in all cases.