Integration of Cylinder Head and Intake Manifold for Powertrain Downsizing and Light Weighting Using Simulations Tools 2017-01-1723

As the commercial vehicle engine heads towards the next generation of stringent emissions and fuel economy targets, all aspects of the internal combustion engine are subject to close scrutiny. Inherently, ICE’s are very inefficient, with efficiency varying between 18 ~ 40%. This efficiency is a function of friction losses, pumping losses and wasted heat. Currently, automotive OEM’s globally are hard at work trying to attack these issues with various solutions to achieve incremental gains.

The leading trend is getting more power from less space, also known as downsizing. Due to the importance of downsizing, direct injection and other technologies, it is imperative to highlight another key area, where OEM’s are expanding their limits to gain those extra few kilometers per liter of fuel i.e. weight reduction. From an emissions perspective, it is estimated that every 50 kg of weight reduced from an average 1,500 kg vehicle cuts CO₂ emissions by 4 ~ 5 grams.

The key areas of the powertrain on which OEM’s will focus their weight reduction efforts will be engine, transmission, exhaust, fuel system, casing, batteries and motors. VECV powertrain team has studied to reduce of about 25 kg in the integration of aluminum cylinder head and intake manifold for light duty commercial vehicles, enabling savings of about 2g of CO₂.

To achieve same existing/proven cast iron cylinder head and intake manifold stiffness for new integral aluminum cylinder head with intake manifold stiffness with defined worst engine loading conditions. First, the existing cast iron 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 cast iron design.

Finite element structural simulation has been used to align the project time plan (design and development time of integration of cylinder head and intake manifold), considering all structural loads i.e. interferences, bolt pre-loads, temperatures, peak firing pressure and compare the stiffness’s with the current/proven cylinder head and intake manifold results. With this integral aluminum cylinder head with intake manifold design, it is estimated that cost savings of up to 30%, reduction in weight by 40% and better fatigue performance (25% - 30%) can be achieved. Hypermesh as a pre-processor and ANSYS as a FE solver are used in this study. The FE simulation tools have helped us in selecting the right parameters for the design and ensure first time right design at the development phase.