Paper Conference

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


Testing and Validating an Equation-Based Dynamic Building Program with ASHRAE Standard Method of Test

Shui Yuan, Zheng O'Neill
United Technologies Research Center, 411 Silver Lane, East Hartford, CT 06108, U.S.A

Abstract: This paper applies ASHRAE Standard 140-2004 to test an equation-based dynamic building model written in Modelica. Unlike other building energy simulation programs such as EnergyPlus and DOE-2, there is a class of simulation programs that is developed to study the dynamics of a building and design control strategies for HVAC equipment. These programs may share the following features: 1) employing a variable simulation time step, which may be down to a fraction of second; 2) not calculating heating/cooling loads directly; 3) a feedback control scheme has to be explicitly modeled. The Modelica-based program in this paper belongs to the above class. Evaluating these programs with ASHRAE Standard 140 requires implementing the standard's thermostat control scheme, and computing loads compatible with the standard. This paper describes the technical challenges we encountered in this testing work and methods we adopted to resolve them. After analyzing the results of a series of comparative tests applied to the Modelica model, we conclude that studied model is capable of predicting the thermal performance of building envelopes and delivering comparable results with respect to prevailing building simulation programs.
Pages: 45 - 52