To compete with the current market trends there is always a need to arrive at a cost effective and light weight designs. For commercial vehicles, an attempt is made to decrease weight of the current design without compromising its strength & stiffness, considering/bearing all the worst road/engine load cases and severe environmental conditions. The topic was chosen because of interest in higher payloads, lower weight, and higher efficiency.
Automotive cylinder head must be lighter in weight, to meet increasingly demanding customer requirements. The design approach for cylinder head has made it difficult to achieve this target. A designer might make some judgment as to where ribs are required to provide stiffness, but this is based on engineering experience and Finite Element Analysis (FEA) of the stand-alone head. Understanding the changes in the head design, will affect the all mating parts of head - the deflection of a complex 3D casting under multiple loads is made even more incomprehensible by the inclusion of non-linear contact elements such as bolts and gasket.
To achieve same existing/proven cast iron cylinder head stiffness for new aluminum cylinder head stiffness with defined worst engine loading conditions. First, the existing CI has been analyzed for defined worst engine loading conditions to know about the stiffness at different known locations. The idea was to come with new design with the same stiffness arrived at the same locations as existing CI design.
Instead of conventional approach, a new FE simulation approach has been adopted to align the project time plan (design and development time of cylinder head) i.e. structural strength of the cylinder head has been evaluated/analyzed, considering all structural loads i.e. Interferences, Bolt pre-loads, Temperatures, Peak firing pressure and compares it with the current/proven cylinder head results. Using the proposed cylinder head design, it is estimated that cost savings of up to 30%, reduction in weight and better fatigue performance (25% -30%) can be achieved. For this study, we have used Hypermesh as a Pre-processor and ANSYS as a FE Solver. The FE simulation tools have helped us in selecting the right parameters for the design and ensure first time right at the development phase.