Resolving Stack Effect Problems in a High-Rise Office Building by Mechanical Pressurization

Abstract

Abstract:In high-rise buildings, the stack effect causes various problems, especially problems related to excessive pressure differences across main entrance doors and elevator doors, particularly in heating seasons. To reduce the stack effect, this study aims to find effective operation schemes for the HVAC systems in a 60-story commercial building, located in Seoul, Korea. Field measurements were conducted to identify the problems related to the stack effect in the building. Computer simulations were conducted to examine the effectiveness of various HVAC operation schemes in reducing the stack effect. Then, an optimum and effective operation scheme was adopted from the computer simulation results and applied in the field. The adopted scheme was used to pressurize the upper zone of the building. Through field application and an adjustment process, a proper amount of air volume was found to effectively pressurize the upper zone of this building, solving the problems related to the stack effect. The required air volume for pressurization was maintained in the building by reducing the volume of the exhaust air (EA) while maintaining a constant volume of outdoor air (OA).

Aerosol transmission of SARS-CoV-2 due to the chimney effect in two high-rise housing drainage stacks

“…The existence of a chimney effect in high-rise buildings is known ( Yu et al, 2017 ); however, to the best of our knowledge, this is the first detailed study of chimney effects on waste stack air flows during non-flushing periods in high-rise housing, and a similar study was reported for a hospital ( Gormley et al, 2014 ).…”

HVAC Operation Schemes and Commissioning Process Resolving Stack Effect Problem and Adjusting According to Changes in the Environment: A Case Study in High-Rise Building in South Korea

“…Consequently, the pressure difference on the elevator door (∆P E2 ) would decrease whereas the pressure difference on the building envelope (∆P B2 ) would increase in the high-rise zone. In contrast, ∆P E2 and ∆P B2 are simultaneously reduced in the low-rise zone because mechanical pressurization of the high-rise zone lowers the NPL of the building [17]. The overall effect of mechanical pressurization of the high-rise zone by reducing V RA is the reduction of air flow rate from the elevator shaft to the office spaces in the high-rise zone.…”

“…As such, mechanical methods that utilize new or existing HVAC systems can be used to distribute pressure throughout a high-rise building in an attempt to resolve the stack effect. Thus, it appears, at least in principle, that mechanically pressurizing the high-rise zone of a building could diminish the net positive pressure acting across the elevator doors and the building envelope, preventing indoor air from leaking out [17]. This can be done by reducing the return air volume (V RA ) and the exhaust air volume (V EA ) of an HVAC system to a minimum while maintaining (or increasing, according to the outdoor air temperature) the outdoor air volume (V OA ) and the supply air volume (V SA ) as shown in Figure 1.…”

“…Many studies have investigated mechanical countermeasures based on the principles of HVAC pressurization [12,15,[17][18][19][20][21]. For instance, one study investigated whether the mechanical depressurization of the high-rise zones and pressurization of the low-rise zones of a high-rise commercial building via HVAC system could help reduce infiltration [6].…”

“…Furthermore, our study is specifically focused on commercial buildings in South Korea. Many high-rise buildings in South Korea were first built without regards to proper architectural and mechanical methods until the early 2000s [17] and thus are occupied at the time of our study. Additionally, architectural methods of reducing the stack effect are more appropriate for residential high-rise buildings because they are already divided into individual household units.…”