Spray penetration in a turbulent flow

Jacek Pozorski, Sergei Sazhin, Marta Wacławczyk, Cyril Crua, David Kennaird, Morgan Heikal

Flow, Turbulence and Combustion

68, 2002, 153-165, 10.1023/A:1020497028986

Analytical expressions for mass concentration of liquid fuel in a spray are derived taking into account the effects of gas turbulence, and assuming that the influence of droplets on gas is small (intitial stage of spray development). Beyond a certain distance the spray is expected to be fully dispersed. This distance is identified with the maximum spray penetration. Then the influence of turbulence on the spray stopping distance is discussed and the rms spray penetration is computed from a trajectory (Lagrangian) approach. Finally, the problem of spray penetration is investigated in a homogeneous two-phase flow regime taking into account the dispersion of spray away from its axis. It is predicted that for realistic values of spray parameters the spray penetration at large distances from the nozzle is expected to be proportional to t(2/3) (in the case when this dispersion is not taken into account this distance is proportional to t(1/2)). The t(2/3) law is supported by experimental observations for a high pressure injector.