Study on CAD for the Complex Combustion Structure in Engine Based on PRO/E

To carry out CAD (computer-aided design) for the complex combustion structure in engine, the top-down method is used. The general model is created in assembly and every part design is finished according to general assembly. The group of piston crankshaft connecting rod is designed and each part is modeled in Pro/E. Pro/E is a solid modeler and this offers considerable advantage for solid model creation. Normally, the geometry is first sketched in 2-D and then extruded in the third direction to generate a 3-D model. Once this base geometry has been created, additional features like holes, rounds, chamfers, fillets, ribs, etc can be added in the finishing stages of the part creation. The center of the bowl does not coincide with the center of the cylinder due to the presence of valve pockets. The obvious advantage of this configuration is that is gives the true geometry of the piston and the presence of connecting rod means that the connecting rod ports can be accommodated when the piston is at the top dead center.