Papers by Author: Huan Wu Sun

Abstract: Based on the studies of the Standard, RNG models and SST model, a vehicle external flow field is calculated with three different models. Calculation results are compared with that of experiment. It is found that the error between the simulation results of the drag coefficient of RNS model and the wind tunnel experimental results are minimal. In the near wall region and airflow separation simulations, the simulation results of SST model are more close to the actual condition compared with standard and RNG models.

Abstract: The fluid magnetic abrasives (FMA) are a new type of precision finishing abrasives which are developed on the basis of the phase transition phenomenon caused by magnetic field. The sediment stability and agglomerative stability are significant characteristics of FMA, and have a great impact on the finishing capabilities and the final surface roughness value. In order to improve the stability of FMA, a new ingredient based on nanometer SiO2 is proposed, the preparation method and the experimental results are also discussed in this paper.

Abstract: The fluid magnetic abrasives (FMA) are a new type of precision finishing abrasives which are developed on the basis of the phase transition phenomenon caused by magnetic field. The rheological effect of FMA is the basis to achieve its finishing function, and has a great impact on the finishing capabilities and the final surface roughness. In order to get a better understanding of FMA finishing mechanism, the rheological effect models of FMA are deduced for the first time, the simulations and the experimental results are discussed as well in this paper.

Abstract: The fluid magnetic abrasives (FMA) are a new type of precision finishing abrasives, which can be used to finish the work-pieces with intricate or complex shape to a quite low surface roughness value. As a key parameter, the material removal rate has a great impact on the finishing capabilities and the final surface roughness. In order to get a better understand of FMA removal mechanism, the numerical analyses was used to simulate the shearing stress field and velocity distribution. The experimental results are discussed as well in this paper.

Abstract: The fluid magnetic abrasives (FMA) are a new type of precision finishing abrasives, which can be used to finish the parts with intricate or complex shape to a quite low surface roughness value. As a key parameter, the magnetic saturation flux density has a great impact on the design of finishing devices and the control of finishing process. In order to measure the magnetic flux density and determine the magnetization curve of FMA, a new apparatus has been developed. The measuring mechanism and the experimental apparatus are presented. The experimental results are discussed as well in this paper.

Abstract: The smart fluid abrasive (SFA) is a suspension of magnetically soft ferromagnetic particles and nonmagnetic abrasives in a carrier liquid. When the SFA is exposed to a magnetic field, a rapid and reversible fluid-to-solid phase transition occurs. Based on these distinctive features of SFA, a new type of precision finishing technology that can be used in the finishing of the revolved surface has been developed, and the finishing results have been proved in our experiments. In this paper, the SFA finishing mechanism and finishing process are presented, the influence of some basic parameters such as magnetic strength, size of abrasives, time of processing and relative motion between abrasives and working surface of work pieces are discussed as well.