Research on Engine Simulation and Assembly Based on Computer Digital Twin.

The current digital engine model only considers the surface geometric errors generated during the part manufacturing process and does not include information such as feature registration constraints and physical properties. The virtual assembly simulation results based on this digital model will be quite different from the actual assembly. This paper proposes a digital twin assembly model expression method that integrates multi-level information. Based on the engine geometry layer model, the shape, pose, and physical characteristics of the engine parts that affect subsequent assembly are considered to generate a real physical engine. A digital twin with identical parts. First, collect feature point cloud, registration element, center of mass information and other information from real engine parts, divide them into geometric shape layer, pose constraint layer, and physical state layer to construct a hierarchical model of engine part features. Secondly, perform reverse modeling for different levels, including geometric shape models based on polynomial fitting and discrete cosine transformation, pose constraint models based on element feature registration, and physical state models based on contact deformation, so as to obtain engine parts containing real information Digital twin. Based on the digital twin of engine parts, the assembly twin frame is constructed by fusing assembly process information. Finally, the research on the engine assembly technology example driven by the digital twin is carried out. Through the interaction and integration of the physical process of engine assembly and the digital model, the intelligence, initiative and predictability of the engine assembly process are improved, and the assembly level is promoted.