Droplet Evaporation in High Pressure Environment

Droplet gasification phenomena at pressures exceeding supercritical pressure of liquid fuels are directly relevant to gas turbine combustors, diesel and liquid rocket. The quasi-steady, “low-pressure, droplet gasification models that are currently being employed in these applications are generally not valid at transcritical conditions, since high-pressure gasification involves processes that are distinctly different from those in a low-pressure environment. These include gas-phase nonidealities, liquid-phase solubility, liquid-vapor equilibrium at the droplet surface, and thermotransport properties.

This research is directed towards the modeling and improved understanding of droplet evaporation, ignition, and combustion behavior under transcritical and supercritical conditions. Both quasi-steady and transient models are being developed to examine droplet gasification at high pressures. The work dealing with the quasi-steady gasification models is aimed at extending their applicability to high-pressure spray simulations by incorporating the important high-pressure effects. The modified high-pressure quasi-steady models are validated using the available experimental data as well as results from comprehensive unsteady droplet models.

Another part of this research is focusing on the development of a unified high-pressure droplet model for spray simulations under transcritical and supercritical conditions. The research is being performed collaboratively with researchers at Sandia National Laboratory and the University of Wisconsin at Madison.