Effects of Injection Velocity and Entrance Airflow Velocity on Droplets Sizing in a Duct

This paper addresses one important aspect of combustion system analysis, the spray evaporation and dispersion modeling. In this study we assume an empty cylinder which is as a simulator for a ramjet engine and the cylinder has been studied by cold flow. Four nozzles have the duties of injection which are located in the entrance of cylinder. The air flow comes into the cylinder from one side and injection operation will be done. By changing injection velocity and entrance air flow velocity, we have studied droplet sizing and efficient mass fraction of fuel vapor near and at the exit area. We named the mass of fuel vapor inside the flammability limit as the efficient mass fraction. Further, we decreased the initial temperature of fuel droplets and we have repeated the investigating again. To fulfill the calculation we used a modified version of KIVA-3V.

Authors:

• M. M. Doustdar
• M. Mojtahedpoor

Keywords:

• Ramjet
• droplet sizing
• injection velocity
• air flow velocity
• efficient mass fraction.

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