Comparisons of Measured and Simulated Performance for CSU House I

Abstract

The heating system for CSU House I is simulated using TRNSYS, and simulation results are compared to the measured performance. The heating system is composed of a liquid collection and storage system, a domestic hot water system, and an air delivery system. The components were modeled using standard TRNSYS components. Measured weather data from the site were employed as the driving function. Measured energy quantities, including the useful gain from solar, that supplied to the house and the domestic hot water system, and the auxiliary were compared to those from the simulation for three periods of six to eleven days each. Comparisons were made on both a daily basis and over the entire period. The simulated energy quantities are found to agree with the data within the accuracy of the measurements. Simulated hourly values of storage tank temperatures are compared to those measured. Although there are differences of up to 5°C between the two at times, the agreement is generally within 2°C. These results help establish the validity of simulation methods for system analysis. Conventional engineering techniques can be used to formulate component models and determine parameter values. Verified simulation models can be then used to predict long term system performance.