Nuclear Technology / Volume 181 / Number 1 / January 2013 / Pages 106-114
Technical Paper / Special Issue on the 14th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-14) / Thermal Hydraulics
A mechanistic droplet deposition model has been developed to quantify the direct-contact heat transfer present in dispersed flow film boiling. Lagrangian subscale trajectory calculations utilizing realistic velocity and temperature distributions in the momentum boundary layer are used to determine the number of dispersed droplets able to achieve contact with the heated wall. Coupling the droplet deposition model with a physical direct-contact heat transfer coefficient model allows the total direct-contact heat transfer to be determined based upon the local vapor mass flux, wall superheat, and vapor superheat. Comparisons to the existing models highlight the more mechanistic nature of the proposed model.