Structural / Mechanical Simulation

The target of simulation in the Structural / Mechanical area is to predict component temperature levels, ensure mechanical integrity of the engine components and to predict structure borne as well as airborne noise of engines.
Temperature Prediction

The trend to increased power output gives rising importance to the reliable prediction of component temperatures, especially the parts forming the combustion chamber. AVL employs a combination of CFD and FEM analysis to predict temperature fields of pistons, cylinder heads, valves, pre-chambers and cylinder liners. In this process CFD analysis is used to calculate local heat transfer coefficients both on the combustion side and on the coolant side. These heat transfer coefficients are then applied to the FEM model of the structure to calculate the components temperature field.

Thermal and Mechanical Stresses

Engine components around the combustion chamber are loaded thermally as well as mechanically. Based on reliable prediction of component temperatures the thermal stress / strain field is analysed. Stress / strain fields for various engine operating conditions allow the evaluation of thermal cycling as well as low cycle fatigue. Superposition of thermal and mechanical stresses leads to evaluation of high cycle fatigue properties in HAIGH diagrams. Reliable prediction of thermal and mechanical stresses allows us to reduce the amount of necessary engine testing.

Engine Structural Vibration

Vibration behaviour of engines is of increasing importance. The AVL developed software EXCITE is applied to predict structural engine vibration as well as to optimise elastic mounting systems of engine frames. AVL is able to calculate the vibration behaviour of the entire engine - generator system thus finding critical torsional vibration modes as well as linear vibration along the co-ordinate axes. Countermeasures in shaft – (crank and cam) as well as in the mounting arrangement and the engine foundation can be pre-optimised in advance of engine build and construction.