Abstract
This paper presents a novel dual-mode search algorithm for refrigerant circuitry optimization, which is implemented in two modules, namely, the knowledge-based computational module (KBCM) and the permutationbased computational module (PBCM). The KBCM determines the appropriate number of tubes for each heat exchanger circuit based on the related non-uniform airflow velocity distribution, whereas the PBCM establishes the optimal or near-optimal sequence in which tubes are linked. The method is designed to maximize the heat exchanger capacity while minimizing the computational costs by excluding infeasible circuits. By combining the KBCM and PBCM techniques, significant gains of 9.64%, 9.87%, 6.96%, and 7.16% in the heat exchanger capacity are observed for the part-load cooling conditions according to the European standard EN14825, particularly for outdoor unit heat exchangers with a non-uniform airflow distribution.