Current Research Projects
Superheated Droplet Vaporization
The research investigates the explosive vaporization of liquid droplets at the superheat limit by computational modeling combined with experiments. The boiling of liquid at high temperatures can be explosive and destructive, and poses a potential hazard for a host of industrial processes. Direct Numerical Simulation (DNS) computations are performed at Southern Illinois University, Carbondale; with companion experiments conducted at the UW. The UW research involves superheating liquid droplets in a heated liquid column, allowing for the initiation of explosive vaporization, and employing high-speed image to visualize the dynamic vaporization behavior, the subsequent droplet oscillations and instabilities, and also detecting and analyzing the accompanying pressure signatures. This research is supported by the National Science Foundation.
Phase-change phenomena in cryogenic propellants
The long-term storage of cryogenic propellants on-orbit is a limiting technology for manned deep-space exploration missions. A joint, NASA-Sponsored program between Michigan Technological University, the UW, and the National Institute for Standards and Technology (NIST) is studying the evaporation and condensation behavior of liquid hydrogen and liquid methane propellants. The accommodation coefficients of evaporating cryogenic hydrogen-methane propellant mixtures are measured at NIST using neutron imaging. MTU is performing a numerical simulation of the evaporating films; the UW component of the research involves computational thermal modeling of the experimental assembly/evaporating film configuration.
Recently Completed Research
Stability, Cellular Structure and Heat Transfer of Evaporating Films
The University of Washington conducted comprehensive laboratory experiments that revealed the evolution of the convective structure in quasi-steady and transient evaporating thin films, and the corresponding impact on heat transfer. The experiment was flown in zero-gravity at NASA Johnson Space Center in May, 2012. The work was supported by NASA.