At this stage, the rapid social progress, the development of China's subway engineering construction has also been improved. Relevant research points out that the future metro power dispatching information managem...At this stage, the rapid social progress, the development of China's subway engineering construction has also been improved. Relevant research points out that the future metro power dispatching information management system should have high precision and powerful real-time monitoring function, which can accurately locate the fault location while carrying out early warning. In addition, through the above process, the related failure events can be specially handled to form the whole process monitoring of the whole system. In the process of establishing the knowledge base, it belongs to the reference process of historical experience information, so as to improve the efficiency of solving power failure and meet the development needs of the whole system.展开更多
In this paper, an algorithm for simulating fluid flow and heat transfer for mold filling of shaped castings is presented. The main features of the algorithm include: 1) a simple but practical technique based on VOF me...In this paper, an algorithm for simulating fluid flow and heat transfer for mold filling of shaped castings is presented. The main features of the algorithm include: 1) a simple but practical technique based on VOF method to determine free surface, 2) an explicit scheme of enthalpy to solve the energy equation more efficiently, and 3) an effective treatment to modify the flux deviation due to pressure iteration. In order to verify these methods, well controlled experiments have been repeatedly done with both water analog and gray iron pouring experiments to record the flow patterns and temperature variations. The calculated results are in accordance with the experimental ones. For the applications, the simulated initial temperature distribution right after mold filling was used to analyse subsequent solidification and to predict shrinkage defects. Actual castings were poured and tested in a foundry plant. The reuslts show that the defects predication with considering fluid flow effects is more precise than that without considering the effects.展开更多
文摘At this stage, the rapid social progress, the development of China's subway engineering construction has also been improved. Relevant research points out that the future metro power dispatching information management system should have high precision and powerful real-time monitoring function, which can accurately locate the fault location while carrying out early warning. In addition, through the above process, the related failure events can be specially handled to form the whole process monitoring of the whole system. In the process of establishing the knowledge base, it belongs to the reference process of historical experience information, so as to improve the efficiency of solving power failure and meet the development needs of the whole system.
文摘In this paper, an algorithm for simulating fluid flow and heat transfer for mold filling of shaped castings is presented. The main features of the algorithm include: 1) a simple but practical technique based on VOF method to determine free surface, 2) an explicit scheme of enthalpy to solve the energy equation more efficiently, and 3) an effective treatment to modify the flux deviation due to pressure iteration. In order to verify these methods, well controlled experiments have been repeatedly done with both water analog and gray iron pouring experiments to record the flow patterns and temperature variations. The calculated results are in accordance with the experimental ones. For the applications, the simulated initial temperature distribution right after mold filling was used to analyse subsequent solidification and to predict shrinkage defects. Actual castings were poured and tested in a foundry plant. The reuslts show that the defects predication with considering fluid flow effects is more precise than that without considering the effects.
