A CFD Investigation Comparing the Performance of an Alternative Valvetrain Design Against a Traditional Poppet Valvetrain
2022-01-0760
03/29/2022
- Content
- The poppet valve is by far the most widely used cylinder head design in internal combustion engines; however, poppet valves themselves create significant flow restrictions during both the intake and exhaust strokes, thus causing a reduction in overall engine efficiency. By removing the restrictive poppet valve from the flow path of air into and out of the cylinder head and allowing air to flow unobstructed, any given ICE engine can achieve higher specific output and greater volumetric efficiency. A new alternative valvetrain design, the flow through barrel valve (FTBV) cylinder head, utilizes straight-cut flow passages that reduce such restrictions. The FTBV, designed by Vaztec, LLC., is a rotary valve system that is designed to be belt driven by the crankshaft, thereby replacing the camshaft and poppet valve system altogether. This paper will primarily explore the differences in flow characteristics between the FTBV and conventional poppet valve cylinder heads using both CFD and flow bench data. Both configurations will be evaluated on the same single cylinder 4-stroke internal combustion engine. CFD simulations were run at multiple valve opening positions on each cylinder head configuration for both intake and exhaust strokes in order to validate the CFD process against flow bench test data for both cylinder heads. The CFD was done in 3-D using overset meshing, as well as using both steady-state RANS and transient URANS turbulence models. Comparison between the two engine configurations will include both intake and exhaust airflow rates as well as overall flow field evaluation using numerous, scalar, vector, and spectral properties.
- Citation
- Robinson, A., Garrett, N., Vaseleniuck, D., and Uddin, M., "A CFD Investigation Comparing the Performance of an Alternative Valvetrain Design Against a Traditional Poppet Valvetrain ," SAE Technical Paper 2022-01-0760, 2022, .