Large eddy simulations of high speed evaporating sprays are conducted to study spray interactions with the gas flow and turbulence generated by the spray. The spray is simulated with a Lagrangian droplet method and a stochastic breakup model together with non-equilibrium, finite-rate heat and mass transfer models. The Lagrangian spray/droplet field is fully coupled with the Eulerian gas flow through mass, momentum and energy coupling terms. The interaction of spray induced gas flow and turbulence with the droplets is studied for different gas chamber densities and temperatures as well as different nozzle sizes and injection pressures. Our results indicate that although the droplet transport and evaporation are both important to the generated gas flow and its interactions with the spray, the major source of momentum transfer to the gas is the high speed vapor generated by evaporation. It is shown that sprays injected from larger nozzles generate more perturbations in the gas due to increase in evaporation rate by higher entrained gas. However, the liquid spray penetration remains unchanged with the variation in injection pressure due to competing effects of evaporation and vapor convection. While the liquid penetration is not significantly affected by the injection pressure, the evaporated vapor penetrates more and mixes better at higher injection pressures due to higher induced gas velocity and turbulence. (C) 2014 Elsevier Ltd. All rights reserved.