关键词: 多联机, 系统仿真, 补气增焓, APF

Abstract: To address the evaluation of the annual performance factor (APF) for vapor injection variable refrigerant flow (VRF) air-conditioning systems, a system-level performance simulation model is developed in this study. The model integrates component models of the vapor injection compressor, heat exchangers, and economizer, and employs a dual-path decoupled solution algorithm for system flow rate and pressure. Based on the ten standard operating conditions defined for APF evaluation, the proposed model is validated against experimental data. The results show that the prediction errors of the model are within 5% for individual operating conditions, while the overall APF prediction error is 2.28%. These results demonstrate that the developed model achieves high computational accuracy and good engineering applicability.

Key words: Variable refrigerant flow, System simulation, Vapor injection, Annual performance factor