Research on mechanism of drag reduction and efficiency improvement of hydrodynamic torque converter with bionic non-smooth surfaces

Inspired by the successful applications of biological non-smoothness, the bionic non-smooth surface was integrated into the design of hydrodynamic torque converter (TC) to conduct the research on the drag reduction and efficiency improvement, the concaves model on non-smooth surface were established according to our analysis with the mechanisms underlying non-smooth unit mediated fluid drag reduction. The friction, shear and turbulent viscous in the concaves and adjacent areas on bionic non-smooth pump surface were found to decline after TC was subjected to transient numerical simulation tests using computational fluid dynamics (CFD) analysis method. The results showed that the head and efficiency of bionic pump was improved, compared with the original model, as well as the over performance of TC, the availability of the proposed design method could be thereby confirmed. As a kind of "green drag reduction" method, the bionic non-smooth surface was firstly applied to TC in this paper, the correlation reflected from non-smooth shell surface of pump can be provided for the design involving the drag reduction on surfaces of other internal components in TC.