Development status of CAE technology abroad

The casting simulation technology originated in the 1940s. With the support of the American Foundry Association, Professor paschkis of Columbia University used a mainframe computer to analyze the heat flow of the gating system. Then in the early 1960s, forsund, a Danish scholar, theoretically analyzed the solidification process of castings through computer simulation, and simulated the temperature field distribution of casting solidification process by finite difference method for the first time. Then, General Motors scholars Henzel and keverian applied the finite difference transient heat transfer program to the simulation of the solidification process of the steam turbine cylinder block, and the temperature field obtained from the simulation is in good agreement with the temperature field measured by the experiment.

In 1966, the heat transfer Committee of the American Foundry Society formulated a long-term research plan for the research of CAE Technology in the solidification process of castings. Pehlke et al. Simulated and calculated the temperature field data of T-type and L-type castings on the basis of the model, and compared it with the measured temperature field. The results show that the thermal resistance between the casting and die interface and the thermophysical properties of materials have a great influence on the simulation results. This lays a foundation for the study of the influence of thermophysical parameters on the interfacial heat transfer coefficient.

The most active research period of casting simulation technology was in the 1980s. A large number of research results were published one after another, and the simulation of mold filling process began to rise. Through the combination of numerical simulation and experimental verification, the team of Yingfu Xinshan of Japan studied the relationship between the internal temperature distribution of the casting at the end of solidification and the central shrinkage porosity and shrinkage cavity, and put forward the critical criterion of the temperature field distribution of the casting and shrinkage porosity. This theory improved the applicability of the casting simulation technology. In 1983, the 50th International Foundry conference was held in Egypt, and a symposium on “computer numerical simulation of casting solidification process” was held, which is the summary and Prospect of research results in this field for nearly half a century. As experts have proposed to use MAC method and SOLA-VOF method to solve the problem of changing boundary conditions, mold filling simulation technology has developed rapidly. In 1984, professors Desai, berry and pehlke also specially formed a scientific research team for the purpose of computer numerical simulation aided design in casting technology. The development of these casting CAE technologies and the establishment of the team have laid the foundation for the wide application, development and commercialization of casting simulation technology in practical production in the future.

While the casting CAE technology has made rapid development in macro simulation, the simulation in micro field has also achieved remarkable results. In 1966, Oldfield et al. Adjusted the heat source term based on the macro temperature field simulation of solidification process. They took the function of growth rate and nucleation rate as the internal heat source term of heat transfer equation, and simulated the microstructure of castings after solidification. In the 1980s, researchers compared the simulated cooling curve with the measured cooling curve in the actual solidification process. The results showed that the accuracy of the structure nucleation and growth model in the solidification process of castings directly affected the feasibility and accuracy of the numerical simulation results. With the development and perfection of crystal nucleation and growth theory, brown and spittle first used Monte Carlo method to study the relationship between liquid phase nucleation and grain growth during metal solidification. The results show that the grain growth in the simulation results is closer to the actual situation, and the nucleation of liquid phase and grain growth are random in space and direction.

France’s research on casting CAE technology is represented by Pechiney company. It has been engaged in numerical simulation research and software development since 1984. The main tasks are jointly completed by the casting alloy manufacturing department of Pechiney company and the team of professional numerical simulation software development company. Subsequently, since 1985, the five Nordic countries have implemented an investment research plan in the name of “huburt”, which studies the temperature field simulation of liquid metal filling and solidification process in stages, then studies the casting CAE microstructure and casting performance prediction, and finally realizes the combination of casting CAE technology and actual casting production to complete the goal of quantitative and directional analysis. With the deepening of the understanding of casting CAE technology, Canada, Russia, South Korea and India have also begun to carry out relevant research on casting CAE technology.