- Author
- Walton, G. N.
- Title
- Computer Programs for Simulation of Lighting/HVAC Interactions.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Sponsor
- Department of Energy, Washington, DC
- Report
- NISTIR 5322, December 1993, 155 p.
- Distribution
- Available from National Technical Information Service
- Keywords
- computers | energy calculation | heating | ventilation | air conditioning | lighting | predictive models | modeling | transient simulation | view factor
- Abstract
- This report describes two computer programs developed for the analysis of lighting/HVAC interations: HLITE and VLITE. VLITE is used to compute the coefficients (view factors) describing radiation interchange between surfaces. These coefficients are used in a thermal network model which is solved by HLITE for transient temperatures and cooling loads. These programs are research tools. HLITE is based on a simple finite volume model for heat transfer combined with sufficiently short time steps to permit explicit time integration in most of the simulation. Controls are modeled in a manner emulating the operation of controls in real buildings. The accuracy of the mathematical solution is appropriate to the models used and data available resulting in a fast, flexible simulation tool. The solution time tends to be directly proportional to the number items in the thermal network and inversely proportional to the time step. The simple methods used in HLITE could provide a general approach to modeling building systems.