In this study, the injection spray of the IQT™ is characterized under atmospheric back pressure using phase Doppler anemometry (PDA). Viscor calibration fluid, which has diesel like fluid properties, is injected using the complete injection system of the IQT™. The high temporal resolution of the PDA method allowed precise time resolved analysis of droplet size and velocity. The AMD and SMD of fuel droplets are found to be 9.3 and 29.3 μm, respectively. The velocity is analyzed as a function of radial position from the nozzle axis. The droplet velocity varies between 130 m/s and 10 m/s depending on spatial position and time after the start of injection. Average velocities on the axis were found to be approximately 78 m/s, decreasing to 15 m/s moving towards the outer spray periphery. The droplet count as a function of radial position suggests that most droplets form a cone angle of 12.6°, which is in agreement with a series of high speed images captured using front light photography.
SAE Technical Papers
Department of Mechanical and Aerospace Engineering

Daviault, S.G. (Stephane G.), Matida, E, Karakolis, M.M. (Michael M.), & Webster, G.D. (Gary D.). (2011). Droplet size and velocity characteristics of the ignition quality tester (IQT™) fuel spray. In SAE Technical Papers. doi:10.4271/2011-01-1816