【正文】 of time, only a few years, but in the world but has a huge user base, get the majority of customers for their support and praise. But the doublesided flow of technology has the following deficiencies: (1) The twosided flow of technology does not fundamentally resolve the issue of a neutral face, they still can not describe some threedimensional features, such as the inertial effect can not describe gravity effect on the melt flow, which fail to predict jet phenomenon, melt cuttingedge Quanyong phenomena. (2) the upper and lower surfaces corresponding to the melt flow front there are differences. As the upper and lower surface of the grid can not be one correspondence, but the grid shape, orientation and size can not be pletely symmetrical, so how the upper and lower surfaces corresponding to the difference between the melt flow front control is within the scope permitted by Difficulties in the implementation of doublesided streaming technology. (3) melt is only along the upper and lower surface flows, in the thickness direction is not to make any treatment, lack of realism. 6 Moldflow39。s 3D (3D) analysis technology uses a true threedimensional solid model flow analysis techniques, through rigorous theoretical derivation and repeated verification, the inertial effect, nonisothermal flow, taking into account factors such as finite element analysis, the melt thickness direction of the physical quantity changes will no longer be ignored, can be a more prehensive description of the process of filling flow phenomena, so that results of the analysis more realistic conditions, applicable to all plastic products. Its threedimensional grid is from the fournode tetrahedron unit. And using the new 3D stereoscopic display technology, can quickly model clearly shows that internal and external flow field, temperature field, stress field and velocity field such as analysis results. For the abovementioned results of the analysis can also be used such as bit lines or equipotential surface display, so that physical models and external changes in the variables show more clearly the case, Moldfiow also offers animation capabilities, through 3D animation display plastic melt in the changes in the flow cavity, allowing users to more intuitively see the design and manufacturing process may encounter problems. But the 3D technology, meshing demanding, more plex equations to calculate the amount of large, long duration and the putational efficiency is low, not suitable for short development cycle and need to be repeatedly revised by CAE verification injection mold design. Therefore, the current peration rate of the technology is not very high, but it will eventually replace the surface flow of technology and doublesided streaming technology. 7 Development Trend of Injection Molding Injection Molding CAE technology, whether in theory or in the application have made great strides, but in the following still needs further improvement and development [45]: (1) mathematical models, numerical algorithms to gradually improve the Injection Molding CAE technology, practicality, depending on the accuracy of the mathematical model and numerical algorithm accuracy. The current mercial simulation software models do not fully consider the physical quantities in the thickness direction of the impact of the software in order to further improve the analysis accuracy and scope to further improve the existing mathematical models and algorithms. (2) the whole process of injection molding simulation At present, the injection molding simulation software are mainly filling, flow, packing, cooling, stress and strain and warpage analysis modules, each module was developed based on independent mathematical models, these models has been simplified to a large extent, ignored of the mutual effects. However, in view of injection molding process, plastic melt filling, flow, packing and cooling are intertwined and affect each other and, therefore, filling, flow, packing and cooling analysis module must be organically bined to carry out coupling analysis, in order to prehe nsively reflect the real situation of injection molding. (3) optimization theory and algorithms, so that CAE technology active to optimize the design Artificial intelligence technologies, such as expert systems and neural works on the design calculations, so that simulation can wisdom to choose the injection molding process parameters, product size and cooling to fix the piping layout