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14
Baseline Simulation
All simulations were performed with SolidWorks Flow Simulation 2025 (CAD-embedded RANS solver).
The computational domain used a Cartesian mesh with local refinement near stockpiles and fence (total
–1.8 million per case; y+ < 5 in near-wall regions). Grid-independence was confirmed via
successive refinement (GCI < 3%).
Turbulence model: Realizable k-
-layer wall treatment
Porous fence: Modeled as porous media with 50% aerodynamic porosity (inertial/viscous
resistance coefficients derived from wind-tunnel correlations)
Inlet: Log-law velocity profile (15 mph at 10 m), 5% turbulence intensity
Particle tracking: Lagrangian Discrete Phase Model (DPM), 1,000 particles per size class (10
µm and 50 µm), Rosin-Rammler distribution, drag + gravity + turbulent dispersion (discrete
random walk)
Boundary conditions: No-slip walls on ground/stockpiles; pressure outlet
Convergence: Residuals < 10
Strengths: High-resolution site geometry, direct coupling of velocity fields to particle trajectories.
Limitations: Steady-state assumption (no gusts), single wind speed, no mechanical disturbance emissions
(addressed separately). Validation: Porous-fence velocity reduction profiles match established windbreak
literature (e.g., 15–20H shelter distance).
Baseline CFD simulations without a wind fence were run for the three key wind directions from the local
wind rose: predominant southwest (SW), secondary south-southeast (SSE), and tertiary west-northwest
(WNW). These cases established reference wind flow and fugitive dust dispersion across the Dominion
Terminal Associates and Kinder Morgan Bulk Terminals.
Under SW winds airflow accelerates over the stockpiles, generating high near-surface velocities and
shear on southern/southwestern faces, entraining fine coal particles and transporting plumes
northeast/east toward residential receptors several hundred meters away.
SSE winds channel flow northward, creating turbulent wakes behind piles and extending dust plumes
toward northern and northwestern community areas.
WNW winds produce cross-site flow from the west-northwest, entraining particles southward and
potentially impacting port areas and receptors south of the terminals.
These unfenced results serve as the benchmark for comparing wind fence performance (80 ft and 100 ft
heights, various layouts) in reducing velocity, shear, and particle transport.
All scenarios used a steady 15 mph inlet wind speed (typical annual average; peak gusts 25–30 mph
–
–15 mph at 10 m
height) (EPA AP-42, 1995). Higher speeds would increase absolute emissions but maintain relative fence
reductions (porous fences remain effective up to 120 mph per literature).”
Simulations Results can be seen in Appendix C
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