Paper Conference

Proceedings of SimBuild Conference 2010: 4th conference of IBPSA-USA


Reconciling Differences in Residential DX Cooling Models in DOE-2 and EnergyPlus

Nathanael Kruis
National Renewable Energy Laboratory, Golden, CO

Abstract: The models used to simulate direct expansion (DX) cooling units in DOE-2 and EnergyPlus are fundamentally different. Though EnergyPlus was adapted from DOE-2, changes have been made to the DX cooling model to root the model in a more analytical technique. In contrast, DOE-2 uses an almost completely empirical curve fit method to estimate performance at off-rated conditions. This paper describes both models and explains how inputs can be generated in DOE-2 for consistency with the model in EnergyPlus. An example DX cooling unit has been characterized with full performance mapping and translated into EnergyPlus inputs to compare outputs against a near-equivalent DOE-2 model with the inputs defined in this paper. Simulating this DX unit in DOE-2 and Energy-Plus models shows good agreement in latent and sensible performance and power consumption.
Pages: 134 - 141