Dynamic local heating performances of typical heating terminals: Evaluation and comparison based on heat matching coefficient

Abstract

Building space heating accounts for an increasing portion of energy utilization in China. To address this problem, the occupant-oriented control part-time-local-space (PTLS) heating strategy, and various novel heating terminal forms have been developed. However, conventional evaluation methods take inadequate consideration of personal space demand, making them unreasonable to reflect the local heating performance of terminals for PTLS mode. Thus, we developed an index—heat matching coefficient (HMC)—from the perspective of matching degree between heat distribution and personal space demand. The concept of space volume was introduced in the performance evaluation, which quantitatively weighs the heat utilization efficiency of demand zone. With this index, the local heating performance of typical convective and radiative terminals (fan coil, radiator, and floor heating) were compared, and a sensitivity analysis of the effects of terminal features and heating loads on the heating performance were conducted. Further, correlations between local heating performances with energy consumption, response time and local discomfort were evaluated. Results suggested that the installation position is crucial to improve the local heating performance for both convective and radiative terminals. The heat consumption and response time showed a negative correlation with the local heating performance. When the HMC reached 1, approximately 34.6% heat was expected to be saved than the uniform built environment for the analyzed scenario. Overall, the HMC is a reasonable index to quantify the local heating performance of terminals, which is of great significance for terminal application and optimization to improve energy-saving and comfort potential.