Research on aerodynamic optimization of high-speed train’s slipstream

Abstract

Slipstream severely affects the safety of trackside workers and equipment. With use of profile superimposition method and vehicle modeling method, parametrization of the whole train is carried out. Then, a slipstream optimization study has been performed, taking components of slipstream in different directions at the standard heights, the drag coefficient of the whole train and the volume of the driving cab as the design objectives. For each design objective, one unique ε-TSVR surrogate model has been constructed. Six final Pareto sets have been obtained on the base of six groups of different fitness functions by using multi-objective particle swarm method. Results reveal that the volume of the driving cab keeps almost the same, compared to the original shape. The velocity components of train-induced wind at the positions 0.2 and 1.4 m above the top of the rail, and the drag coefficient of the train are reduced by 11.6%, 33.9%, 24.7%, 25.9% and 13.0% respectively. Sensitivity analysis reveals that the length of the streamline, the height of the train and the width of the train influence significantly on the aerodynamic performance, and the train with a tall and thin streamline will benefit in reducing the slipstream and aerodynamic drag.

Numerical investigation on the aerodynamic resistances of double-unit trains with different gap lengths

“…Operating mileage continues to increase, as does passenger volume (Sun et al, 2020;Tian, 2019). However, the cost of improving passenger capacity by increasing train frequency is too high, and it may increase the safety risks associated with rail transportation (Guo et al, 2018).…”

Shape Optimization with a Flattening-Based Morphing Method

“…The shapes of engineering objects are significant design factors that affect their functionality, particularly their aerodynamic aspects. For example, engineers have developed the shapes of ground vehicles for many years to reduce aerodynamic drag and increase fuel efficiency [1][2][3][4][5]. They have also attempted to reduce wind noise and increase the driving stability at high-speed operating conditions via the modification of a vehicle's body shape [6][7][8][9].…”