Efficient Ventilation Design: CityLine Block 3 Computational Fluid Dynamics Study - Sunnyvale, CA
Category: Enclosed Parking Garage
Overall Area: 280,000 ft²
Services Provided: Computational Fluid Dynamics (CFD) Analysis
Completion Date: 2021
Contractor: Silicon Valley Mechanical
Project Description
Challenge
The CityLine Block 3 retail office development in Sunnyvale, California, features a two-level underground enclosed parking garage designed for efficient ventilation. The original design included two large vehicle entry/exit openings that provided outdoor air for ventilation, supplemented by three supply fans and multiple disruption fans dispersed throughout the garage to control carbon monoxide (CO) levels.
However, the project team sought to optimize the ventilation system by investigating whether removing the three supply air openings and all disruption fans would still maintain safe air quality standards.
Solution
Pragmatic Professional Engineers (Pragmatic PE) was engaged to conduct a Computational Fluid Dynamics (CFD) analysis to evaluate the impact of these proposed design modifications. Using advanced CFD modeling, our team simulated the revised ventilation scenario—where all air intake relied solely on the two garage door openings—to assess whether it could still adequately disperse carbon monoxide emissions from vehicle operations.
Results & Impact
Validated Design Efficiency: Our analysis confirmed that the garage ventilation system, even without the additional supply and disruption fans, was sufficient to maintain carbon monoxide concentrations within safe, code-compliant levels.
Cost Savings & Energy Efficiency: By eliminating the need for additional fans, the project reduced both capital expenditure and ongoing energy consumption, contributing to a more cost-effective and sustainable solution.
Ensured Regulatory Compliance: Our CFD analysis provided the necessary validation to support the design changes while ensuring compliance with indoor air quality and safety regulations.
The successful study allowed the project team to implement a streamlined ventilation strategy, reducing mechanical complexity while maintaining occupant safety and environmental compliance.