CFD Modeling and Simulation for the Waller Creek Tunnel/8 th St. Lateral Junction Alden Research Laboratory Inc. 30 Shrewsbury St., Holden, MA Preliminary Results By:

CFD Model Geometry

103.41’ 100’ Transition 50’ = 16’ 57.75’ = 16’ Plan View Profile View A A B B Section A-ASection B-B 10 ‘ ’ ’ R = 10.21’ R = ’ Θ = 45 o

Boundary and Flow Conditions Tunnel Inflow Outflow Junction Inflow

Computational Mesh: ~ 310,000 cells

Waller Creek (WC) Tunnel Flow Scenarios Return Period1 yr2 yr5 yr10 yr100 yr500 yr Proposed - Lag Tunnel / Peak Intervening Flow ( 8th Street Lateral Junction) Tunnel Flow (12th St. Inlet) th St. Connector Tunnel Flow % Flow of 8th St. Connector Tunnel41.1%34.2%27.7%25.5%26.8%27.4% Proposed - Lag Tunnel / Peak Intervening Flow ( 4th Street Lateral Junction) Tunnel Flow (12th St. Inlet + 8th St. Inlet) th St. Connector Tunnel Flow % Flow of 4th St. Connector Tunnel21.7%18.2%14.3%13.0%12.8% Flow Scenarios:

Lag Tunnel / Peak Intervening Flow ( 8 th Street Lateral Junction) 100 Year Return Period (Uniform Inflow at Lateral Junction Inlet)

Lag Tunnel / Peak Intervening Flow ( 8 th Street Lateral Junction) 1 Year Return Period (Non-uniform Inflow at Lateral Junction Inlet)

Lag Tunnel / Peak Intervening Flow ( 8 th Street Lateral Junction) 1 Year Return Period (Uniform Inflow at Lateral Junction Inlet)