Nontangential injection of single and two-phase jets into subsonic flow

The large amount of information available on the penetration of pure gas jets into a cross flow makes it attractive to represent a gas-particle jet by an equivalent gas jet. Perfect equivalence required that the two jets have the same average density, mass flow and momentum flux. It was shown that for moderate particle concentrations, exact equivalence is possible only if the particles are in velocity equilibrium with the gas. Experiments were performed with 33 micrometers glass beads carried by a nitrogen jet injected into a cross stream of air. Jet and stream velocities ranged over several tens meters per second, and the particle flow rate varied between 2.3 and 25 times that of the carrier gas. Particle velocities were obtained with a laser-Doppler system and found to be between 40 and 60% of the velocity of the carrier gas. The concept of an equivalent gas jet therefore was expected to apply.