Paper Conference

Proceedings of SimBuild Conference 2008: 3rd conference of IBPSA-USA


The EnergyPlus UFAD Module

Qing A. Liu, Paul F. Linden
Ove Arup & Partners, San Francisco, U.S.A
University of California, San Diego, U.S.A

Abstract: This paper discusses the development of an Underfloor Air Distribution (UFAD) interior zone model that has been implemented in EnergyPlus UFAD module for energy simulation. The theory of this UFAD module is based on the understanding of the fluid dynamics of UFAD systems (Liu and Linden 2006) and the qualitative and quantitative comparisons between small-scale laboratory experiments and full-scale room tests, both of which are described in this paper. The comparisons show that a two-zone stratification forms at steady state. For multiple-diffuser cases, the same trends of the stratification profiles were found in experiments with both scales. Non-dimensional parameters Gamma and Phi were defined to describe the inputs of the system and the resulting stratification of the space, respectively. The data from the laboratory experiments and the test room fall on a unique relationship of Gamma and Phi, which determines the room stratification. It is these equations that have been implemented in EnergyPlus UFAD simulation module.
Pages: 23 - 28