Greenhouse window U-factors under field conditions
Field measurements of U-factor are reported for two projecting greenhouse windows, each paired with a picture window of comparable insulation level during testing. A well-known calorimetric field test facility was used to make the measurements. The time-varying U-factors obtained are related to measurements of exterior conditions. For one of the greenhouse windows, which was the subject of a published laboratory hotbox test and simulation study, the results are compared with published test and simulation data and found to be in disagreement. Data on interior and exterior film coefficients are presented, and it is shown that the greenhouse window has a significantly lower interior film coefficient than a conventional window under the same interior conditions. This is advanced as a possible explanation of the disagreement.
- Research Organization:
- Lawrence Berkeley National Lab., Environmental Energy Technologies Div., Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Assistant Secretary for Energy Efficiency and Renewable Energy, Washington, DC (United States)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 674940
- Report Number(s):
- LBNL-40448; DA-374; CONF-980123-; ON: DE98054169; TRN: AHC29820%%404
- Resource Relation:
- Conference: 1998 ASHRAE winter meeting, San Francisco, CA (United States), 17-21 Jan 1998; Other Information: PBD: Jun 1997
- Country of Publication:
- United States
- Language:
- English
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