A preliminary numerical study of the external scalar field of a fluidic precessing jet (FPJ) flow is reported. The unsteady Shear Stress Transport (SST) model, which showed good agreement with the measured velocity field of flows within a FPJ nozzle, was adopted to assess the effect of the turbulent Schmidt number, Sc_t, on the simulated scalar field. The simulated jet axis concentrations with three turbulent Schmidt number values, Sc_t =0.5, 0.9 and 1.3 have been compared against the measured results in the literature. It is found that the SST model over-predicts the centreline concentration of the jet in the near field downstream from the exit of the FPJ nozzle, while under-predicts it in the far field. An increase in Sc_t number causes the simulated jet to be more distributed away from the axis of the confinement, which is in contrast to the measured data. The best agreement with the measured result was achieved by adopting a Sc_t number of 0.5. However, due to the complexity of the FPJ flow, it is not feasible for a two-equation URANS model to reliably reproduce the scalar field by simply adjusting the turbulent Schmidt number.