A numerical procedure is presented to evaluate the tracer trajectory that results from single jet injection into a pipe at arbitrary angles. Numerical and asymptotic results with experimental data. It is found that the numerical procedure provides an accurate prediction of the jet trajectory, particularly, when the injection angle is either normal or upstream. Moreover, the numerical solutions provide estimates of both the jet diameter and concentration (or temperature) decay. Example trajectories are computed for a range of injection angles 30 degrees less than or equal to theta(o) less than or equal to 150 degrees and the profiles are found to be insensitive to the jet-to-pipe velocity ratio when jet coordinates are sealed with the jet momentum length.