Extension of Bubble Entrainment Models to Rectified Diffusion and Ship Maneuvering in Waves
Abstract
Extension of Bubble Entrainment Models to Rectified Diffusion and Ship Maneuvering in WavesThis project aims at extending the capabilities of existing bubble entrainment models in the code REX to enable computation of the two-phase flow around ships operating in a wide range of conditions. These conditions include low, moderate and high speeds in calm water and waves, as well as maneuvers under these conditions. The bubble entrainment model based on turbulence/free surface interaction frm Castro et al. (2016) will be extended to account for formation of vortices normal to the surface, which can transport bubbles deeper than tangential vortices. Developments to the existing wave impact entrainment model (Li et al. 2016) include the ability to handle oblique impact of small-scale unresolved waves (chop), as well as resolved large waves. Microbubbles produced by rectified diffusion of background nuclei traveling through low-pressure regions on propeller and appendages will be incorporated with a Lagrangian/Eulerian approach, where a number of nuclei will be injected upstream of regions where they have the potential to grow into microbubbles. These nuclei are transported and tracked using Rayleigh-Plesset and a diffusion equations to compute the growth, and the resulting bubble group number densities will be incorporated into the Eulerian two-fluid model after scaling by ratio of nuclei number density with the injected particle number density. The project also will implement into REX and assess the entrainment models developed at MIT. Validation and calibration for a variety of canonical flows (hydraulic jump, breaking wave) and marine craft flows (Athena R/V, Kaan flat bottom boat) is planned, as well as demonstrations of maneuvers in waves for Navy surface ships.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 17, 2020
- Source ID
- N000142012058
Entities
People
- Pablo M. Carrica
Organizations
- Office of Naval Research
- United States Navy
- University of Iowa