(588cb) Wind Tunnel Tests for Validation of Carbon Dioxide Pipeline Consequence Assessment Modeling

Project Skylark is a Joint Industry Project (JIP) planned to advance safety standards in carbon dioxide (CO₂) pipeline operations. The collaborative initiative is led by DNV in conjunction with the UK HSE Science Division (HSE SD). As a partner in the project, the Chemical Hazards Research Center (CHRC) is developing wind tunnel data sets suitable for assessing the capabilities and limitations of dispersion models for: CO₂ pipeline risk assessment, permitting studies, and emergency planning and response. Experiments will be conducted to study the initial behavior of a typical pipeline release on flat terrain, the behavior of a cloud released over sloping terrain, and the behavior of a cloud released over complex terrain. The wind tunnel experiments will be conducted at 50:1 field scale to model scale. The wind tunnel simulates neutral atmospheric conditions, and surface roughness deployed in the tunnel can be configured to produce different ambient atmospheric turbulence levels. In field-scale experiments, the initial cloud density will depend on several factors including dry ice formation and deposition, water condensation and deposition, and initial cloud temperature which would be expected to be near the sublimation temperature of CO₂. To consider the impact of initial density, experiments will be conducted in two phases. In the first phase, ambient temperature CO₂ will be released in the wind tunnel to study behavior under typical release conditions at various wind speeds. In the second phase, gas mixtures will be used to produce clouds that are denser than the gas released in the first phase. The density of released gas in the second phase will be adjusted based on field scale observations. Gas concentration measurements are planned. Repeated releases will be conducted under otherwise identical conditions to quantify the variability and intermittency that is expected in a field scale release. The three-year program is just beginning, and initial experimental results will be discussed.