Research on numerical investigation and test verification of brake performance in a hydrodynamic tractor- retarder assembly

The brake performance of a hydrodynamic tractor-retarder assembly, which is the combination of torque converter and hyaulic retarder, was studied to explore its work mechanism. Spiral vortex distribution pattern of internal flow field in the assembly was discovered on the basis of reasonable boundary condition, where runaway speed of stator was determined by CFD analysis. Comparison of experimental data and flow field analysis shows that accurate brake performance of hydrodynamic tractor-retarder assembly can be calculated only by 3D flow field analysis presently and numerical simulation results is close to experimental data, and approximate linear relationship exists between runaway speed of stator and rotating speed of pump.