Abstract: With the increasing application of aluminum tubes in air conditioning systems, some companies are exploring the scheme that using the aluminum-tube and microchannel heat exchangers as replacements for conventional copper-tube heat exchangers. Aims to optimize the groove parameters of Φ5 aluminum inner-grooved tubes and provides an analytical model for refrigerant phase-change heat transfer inside the tube. The heat transfer capacity per unit material consumption is analyzed by comparing the parameter (KA/m)_e/(KA/m)₀ at equal pump power. The influence of 5 groove parameters on heat transfer performance is investigated. An aluminum-tube heat exchanger with the optimal parameters is prepared, and the results are compared with a copper-tube sample by conducting heat exchanger performance experiments. The results show that groove number and height significantly impact heat transfer performance. The optimal parameters of an aluminum tube are 0.156 mm groove base width, 0.20 mm groove height, 45 groove number, 30° groove tip angle, and 20° helical angle. After optimization, the cooling and heating capacity of the aluminum-tube heat exchanger can reach 102.1% and 99.7% compared to the copper tube sample, respectively.

Key words: Fin-tube heat exchanger, Aluminum inner-grooved tube, Parameter optimization