Forming mechanism of three-dimensional integral fin based on flat surface

Abstract

To improve heat-transfer performance, a novel integral three-dimensional fin-structure on the plat surface was presented to increase the evaporation efficiency. The three-dimensional fin-structure is composed of a spiral micro-groove and multi radial micro-grooves. Both ploughing-extrusion (P-E) and stamping were used to form the integral-fins with a connection between radial and circumferential directions. Based on the SEM results, the relationships among P-E speed v_P-E, rotational speed n_p and feed f_p, and among interference length L_i, stamping feed angle θ_c and stamping depth a_c were analyzed. The effects of processing parameters on the groove morphology and the matching relationship between parameters were also discussed. The integral finned surface with micro-grooves and cracks can be obtained under such processing conditions: P-E depth a_p=0.3 mm, a_c=0.3 mm, the interval of helical groove d_p=1.24 mm, θ_c=2° and n_p=50 r/min.

Keywords

three-dimensional integral fin / ploughing-extrusion / stamping / micro groove / enhanced boiling

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