Heat Recovery in Building Envelopes
Infiltration has traditionally been assumed to contribute to the energy load of a building by an amount equal to the product of the infiltration flow rate and the enthalpy difference between inside and outside. Application of such a simple formula may produce an unreasonably high contribution because of heat recovery within the building envelope. Previous laboratory and simulation research has indicated that such heat transfer between the infiltrating air and walls may be substantial. In this study, Computational Fluid Dynamics was used to simulate sensible heat transfer in typical envelope constructions. The results show that the traditional method may over-predict the infiltration energy load by up to 95 percent at low leakage rates. A simplified physical model has been developed and used to predict the infiltration heat recovery based on the Peclet number of the flow and the fraction of the building envelope active in infiltration heat recovery.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Assistant Secretary for Energy Efficiency and Renewable Energy. Office of Building Technology, State and Community Programs. Office of Building Technology Assistance (US)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 787111
- Report Number(s):
- LBNL-47329; R&D Project: 474402; TRN: AH200134%%45
- Resource Relation:
- Conference: ASHRAE/DOE/BETEC Conference: 'Performance of the Exterior Envelopes of Whole Buildings VIII', Washington, DC (US), 06/05/2001; Other Information: PBD: 1 Jan 2001
- Country of Publication:
- United States
- Language:
- English
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