Papers by Author: Wu Di

Abstract: In ordered to realize dynamic simulation of working process in the rotary engine, a spark-ignition rotary engine is chosen as the research object, the detailed calculated models have been established including combustion model and turbulence model. With numerical simulation, same important information in the cylinder is obtained, such as the velocity, temperature fields and flame propagation. Furthermore, the effect of pocket location on the flame propagation is analyzed. The results show that under the calculating condition, when the pocket is located at the rear of rotor, the rate of combustion and the peak pressure are better than that of other cases, and NO emissions increases accordingly. This study provides some theory guidance for the determination of best pocket location under different working conditions.

Abstract: Temperature of the head, the waist, the bottom and angle of the bottom of same heavy rail lying on the cooling bed is tested continuously, time interval is 5min, which can provide the basis for prebending process. Additionally, the U75V 60Kg/m heavy rail straightening processes using the horizontal and edge roll compound straightening machine is discussed in this paper, and contrasts the cross-section dimension and straightness of heavy rail before and after being straightened, which is important to make certain of optimum straightening parameters.

Abstract: A viscoplastic self consistent model was developed using a rate sensitive constitutive relation, isotropic hardening law, and considering the interaction between the grains and their surroundings. The model was applied to simulate the mesoscopic responses of fcc polycrystalline aggregate during tensile deformation. The macro textures, the grain rotation behaviors, plastic strain and stress heterogeneities, and slip system activities were investigated. The model successfully predicts the typical tensile textures, the grain rotations toward (111) and (100) directions and the orientation dependent slip activities, etc. The simulation results are qualitatively in agreement with experimental measurements and theoretical predictions.