Biomimetic duct tee for reducing the local resistance of a ventilation and air-conditioning system

Publication date: 1 February 2018
Source:Building and Environment, Volume 129
Author(s): Ran Gao, Kaikai Liu, Angui Li, Zhiyu Fang, Zhigang Yang, Beihua Cong
The energy consumption of air transportation and distribution systems in ventilation and air-conditioning ducts has drawn worldwide attention. In this study, a method for reducing the local resistance in a duct tee using a protrusion structure is proposed based on biomimicry of the branched structure of plants. The resistance of a duct featuring protrusions is compared with that of the five traditional types of tees. The resistance mechanism of the protrusion structure is analyzed, and the effectiveness of the proposed method is verified through experiments. The resistance of a duct tee with protrusions is much smaller than that of all traditional tees. Relative to the traditional duct tee, the resistance reduction rates of the duct tee with protrusion structure in two flow directions are 36% and 21%. In cases of high flow and low aspect ratios, the resistance becomes negative; that is, the resistance reduction rates are greater than 100%. The protrusions significantly reduce the energy dissipation rate of the duct tee. The effect region of the energy dissipation for duct tees is smaller than that of traditional tees.