Modeling of Underwater Liquid Releases, Slick Transport & Evaporation V.M. Fthenakis and U.S. Rohatgi Department of Advanced Technology Brookhaven National Laboratory InternationalC onference and W orkshop on M odeling the C onsequences of A ccidentalR eleasesofH azardousM aterials,San Francisco,C A ,Sept.27-30,1999
29
Embed
Modeling of Underwater Liquid Releases, Slick Transport & Evaporation
Modeling of Underwater Liquid Releases, Slick Transport & Evaporation. V.M. Fthenakis and U.S. Rohatgi Department of Advanced Technology Brookhaven National Laboratory. Discharge Model. APG Spill from a Barge in Mississipi River -Baton Rouge, Louisiana. Overview. - PowerPoint PPT Presentation
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Modeling of Underwater Liquid Releases, Slick Transport & Evaporation
V.M. Fthenakis and U.S. Rohatgi
Department of Advanced Technology
Brookhaven National Laboratory
International Conference and Workshop on Modeling the Consequences ofAccidental Releases of Hazardous Materials, San Francisco, CA, Sept. 27-30, 1999
Discharge Model
VAPOR
FLUID
WATER
River Current
APG Spill from a Barge in Mississipi River -Baton Rouge, Louisiana
APG Spill from a Barge in Mississipi River -Baton Rouge, Louisiana
OverviewOverview
Consequence analysis requires modeling of 1) discharge, 2) transport in water, 3) evaporation and 4) atmospheric dispersion
Previous discharge models limited to initial hydrostatic pressure difference (Dodge, 1980; Fannelop, 1994) . A new discharge model was developed
Oil slick transport in rivers (Shen & Yapa, 1988) Multicomponent evaporation ( PAVE) Atmospheric Dispersion (ALOHA, ISC)
Verification & Sensitivity Analysis Spreading & Evaporation Model Application to Real Incident Atmospheric Dispersion Modeling Verification of Predicted Concentrations
Discharge Model .
VAPOR
FLUID
Inflow WATERof WATER
River Current
Outflow
Discharge Due to OscillationsDischarge Due to Oscillations
VAPOR
FLUID WATER
WATERWaterInflow
River Current
Discharge Due to OscillationsDischarge Due to Oscillations
VAPOR
FLUID WATER
Outflow
WATER
River Current
Discharge Due to OscillationsDischarge Due to Oscillations
VAPOR
FLUID WATER
WATERWaterInflow
River Current
Discharge ModelDischarge Model Assumptions: Isothermal Outflow and/or Inflow Incompressible, Immiscible fluids; Ideal gas expansion in the vessel’s void space Based on analytical solutions for non-vented and vented
vessels; discharges due to hydrostatic pressure and periodic oscillations from waves and bouncing
The model predicts Water inflows / fluid-and-water outflows with time Change of void space and fluid inventory with time Change of water level in the barge with time Critical water layer thickness and inventory in steady-state
Discharge Model -Phase 1 VerificationDischarge Model -Phase 1 Verification
Gas-phase pressure Temperature & Saturation Pressure Depth of the break Area of the break Discharge coefficient Fluid density Amplitude of vessel movement Period of vessel movement
River Spreading Modeling River Spreading Modeling
Advection of the slick due to river currents and the wind
Spreading of the slick due to gravitational, inertia, viscous and surface tension forces
Multi-component evaporation
Spreading & Evaporation ModelSpreading & Evaporation Model
Change of spill thickness, width, leading edge andtrailing edge as a function of time
Spill volume decreasing due to evaporation
)48(
0 0
hXdydxdt
Xhd LEX h
LELE
Evaporation ModelingEvaporation Modeling
Experimental studies -(crude oil, Payne et al. 1984; chlorobenzene and toluene, Waden and Triemer, 1989)
PAVE multi-component evaporation model Diffusion through the liquid phase and mass transfer
from surface. Heat conduction to water, convection to the
atmosphere, solar radiation, atmospheric radiation and evaporative cooling
Verified with chlorobenzene and toluene evaporation data