Numerical and experimental validations of the theoretical basis for a nozzle based pulse technique for determining building airtightness

Cooper, Edward; Zheng, Xiaofeng; Wood, Christopher J.

Abstract

Motivated by intentions of avoiding large net fluid flow and enabling a more practical airtightness test for large buildings, a low-pressure Pulse pressurisation technique was developed for measuring building airtightness at pressures that are considered more representative of that experienced by buildings under natural conditions. Due to the short and dynamic operation, this technique is able to minimize wind and buoyancy effects during the measurement of building pressure. The investigation, based on the “quasi-steady” temporal inertia model, explores a technique that generates a pressure pulse inside a building by releasing a known amount of air pulse over 1.5 s using a compressed air tank. The volumetric flow rate of the air pulse released from the tank is obtained by measuring the transient pressure in the air tank during a test run. The air leakage through the building envelope is then obtained by accounting for the compressibility of indoor air. Simultaneously, the pressure variation within the envelope of test building is monitored. Therefore, the leakage-pressure relationship of the building envelope can be obtained. The validity of the theoretical model and the assumptions on which the model is based are validated using experimental and numerical investigations.

Citation

Cooper, E., Zheng, X., & Wood, C. J. (2021). Numerical and experimental validations of the theoretical basis for a nozzle based pulse technique for determining building airtightness. Building and Environment, 188, Article 107459. https://doi.org/10.1016/j.buildenv.2020.107459

• Journal Article Type: Article
• Acceptance Date: Nov 9, 2020
• Online Publication Date: Nov 18, 2020
• Publication Date: Jan 15, 2021
• Deposit Date: Nov 18, 2020
• Publicly Available Date: Nov 19, 2021
• Journal: Building and Environment
• Print ISSN: 0360-1323
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 188
• Article Number: 107459
• DOI: https://doi.org/10.1016/j.buildenv.2020.107459
• Keywords: Building airtightness; The Pulse technique; Unsteady approach; Steady pressurisation method; Experimental and numerical validations
• Public URL: https://nottingham-repository.worktribe.com/output/5053071
• Publisher URL: https://www.sciencedirect.com/science/article/abs/pii/S036013232030826X