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High cycle fatigue material properties are not uniformly distributed on cylinder heads due to the casting process. Virtual Aluminum Casting (VAC) tools have been developed within Ford Motor Company to simulate the effects of the manufacturing process on the mechanical properties of cast components. One of VAC features is the ability to predict the high cycle fatigue strength distribution. Residual stresses also play an important role in cylinder head high cycle fatigue, therefore they are also simulated and used in the head high cycle fatigue analysis. Cylinder head assembly, thermal and operating stresses are simulated with ABAQUS™. The operating stresses are combined with the residual stresses for high cycle fatigue calculations. FEMFAT™ is used for the high cycle fatigue analysis. A user-defined Haigh diagram is built based on the local material properties obtained from the VAC simulation.

A successful piston design requires eliminate the following failure modes: structure failure, skirt scuffing and piston unusual noise. It also needs to deliver least friction to improve engine fuel economy and performance. Traditional approach of using hardware tests to validate piston design is technically difficult, costly and time consuming. This paper presents an up-front CAE tool and an analytical process that can systematically address these issues in a timely and cost-effectively way. This paper first describes this newly developed CAE process, the 3D virtual modeling and simulation tools used in Ford Motor Company, as well as the piston design factors and boundary conditions. Furthermore, following the definition of the piston design assessment criteria, several piston design studies and applications are discussed, which were used to eliminate skirt scuffing, reduce piston structure dynamic stresses, minimize skirt friction and piston slapping noise.

A bridged valve train configuration exhibits complex dynamic behavior due to the uniqueness of the special elephant foot/bridge/valve structure. Consequently, this system arrangement presents significant design challenges in system stability at high speed, high load, wear, no-follow and valve seating velocity, etc. An efficient way to gain a thorough understanding of the behavior of this type of valve train system and to drive the valve train design improvement is through the use of an effective dynamic simulation tool. In this paper, an advanced CAE tool developed by Ford Motor Company for the bridged type valve train simulations has been described. This automated CAE tool provides a complete virtual ADAMS-based simulation environment for the pushrod bridged valve train system analysis. This paper also presents the correlation and validation between the simulations and the measurements. The design analysis for the bridged valve train has been discussed briefly in this paper.