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In the design of aluminum (Al) cooling system components for heavy duty diesel engines, coolant flow velocities are critical to the durability of the parts. The geometries of the individual component parts used in the system must be designed to minimize turbulence which will affect the rate and type of corrosion. In addition, flow passages must be “sized” to maintain coolant velocities below a critical value. In high velocity flow, a combination of the mechanical damage produced by the impingement of a liquid on a metal surface and the inherent corrodibility of the metal may result in erosion-corrosion and impingement attack. Aluminum alloys are very prone to this type of corrosion damage because of the low inherent hardness of the material as compared to other alloy systems. The development of aluminum cooling system parts for a new 15 liter diesel engine was undertaken to lower weight and make a more compact design for the engine profile.

In this paper, two approaches are presented for steady state fluid flow calculations in complex diesel engine exhaust valve-port geometries. The first one simplifies the geometry and concentrates on the fine details in the valve seat region using two-dimensional axisymmetric Navier-Stokes equations. Various configurations are examined to show the usefulness of the approach for design purposes. The second approach is illustrated by a full 3-D simulation of the flow in a complex cylinder-valve-port geometry with two exhaust valves. Details are presented on the generation of the geometry and the mesh, and important flow features from the CFD solution are described. For both approaches, limited available experimental information is presented in support of the computational results.