2016 ASHRAE Winter Conference

This paper is the first part of two papers that report on the results of the ASHRAE-RP 1468 project. This paper presents an overview of the project and the three volumes of documentation included in the final report. The purpose of the project was to produce reference models and guidelines for developing software to automate thermal model creation from a Building Information Model (BIM) into a Building Energy Simulation (BES) for energy simulations. This paper describes the methods of the research and presents highlights of the guidelines.

This paper presents an experimental and numerical study focusing on the development of control-oriented thermal models of varying resolution for an actively charged/discharged phase change material thermal energy storage (PCM TES) system intended for building integration. This PCM TES system consists of five layers of PCM panels with an air channel between the middle layers. Conditioned air is drawn through the cavity to charge and discharge the PCM. The PCM TES system is tested in an environmental chamber where its dynamic response was carefully monitored. The monitored data is used for model development and validation. Compared to a detailed 30th order RC model, simplified 4th order and 2nd order models are shown to be able to satisfactorily predict the thermal energy storage and release of the PCM TES system. To simplify the PCM characterization input and to reduce the simulation time, a five-parameter equation is developed to model the PCM specific heat and a four-parameter equation for its thermal conductivity. The presented modeling methodology is applicable for similar PCM TES systems with multiple PCM layers and air flow channels.

This paper presents an experimental and theoretical study of the dynamic response of low mass residential buildings and their respective space heating peak demands for different room temperature set point profiles, with a focus on the impact of thermal model resolution on the peak demand calculation. Experiments were conducted at two identically constructed and highly instrumented houses. The wood floor of one of them is covered with carpet. Their dynamic response to different ramping set point profiles is monitored and analyzed. Equivalent and physically meaningful RC network thermal models for the purpose of model based control are developed for a north zone of the houses.