Design/Analysis and Development of Cylinder Head for High Performance 3 Cylinder CRDi Euro-V Diesel Engine for a High Combustion Pressure of 200 Bar

摘要

This work is a part of program on "Development of High Performance DI, 3-Cylinder CRDI Diesel Engine to meet Euro-IV/V Emission Norms focused on automotive passenger car application purpose. This is a 3-cylinder, TCIC engine designed for combustion pressure of 160 bar max for first stage which is being upgraded to 200 bar max in the second stage. Cylinder Head design is a part of complicated configuration whose construction and principal dimensions are dependent on the size of inlet and exhaust valves, fuel injectors positioning and mounting, port layout and swirl and shape of combustion chambers. The cylinder head of a direct-injection diesel engine has to perform many functions. It has to bring charge air to the cylinder and exhaust gas from the cylinder, with minimum pumping loss and required swirl and other properties of charge motion. This paper describes about the robust, reliable and an integrated approach used in design and development of a cylinder head for a high power density engine, which can be adopted for automotive application. Design of Head is carried out within several design, assembly and manufacturing constraints such as to maintain a specific cylinder center distance, four valve layout, internal EGR passage, CGI material, incorporation of various accessories, viz. manifolds, thermostat housing, cam carrier, glow plugs integrated with pressure transducer, etc. Major focuses have been given on cylinder head layout, bolt pattern, port layoutting, water jacket core optimization for flow and strength while going for the design. In addition, approach involved in design, development, testing and optimization of the ports had been discussed. Statistical database, quality tools like DFMEA, DFMA, etc., classical design methods, advanced CAD-CAE and simulation tools helped us in developing this cylinder head with minimum iterations in reduced cycle time. Experimental validation of above-mentioned design parameters is carried out as a part of design verification and validation. Results are elaborated to show the effectiveness of an integrated approach used for this development program.