Cam Phaser Simulation in GT-Suite

Abstract

Cam phasers enable variable valve timing by changing the angular position of the camshaft relative to the crankshaft. In heavy-duty diesel engines, cam phasing can support functions such as thermal management, engine braking, and potential replacement of certain conventional engine components. Understanding the internal behaviour of a cam phaser is therefore important for further system development. However, existing supplier models provide limited access to the internal hydraulic and mechanical behaviour of the system. This thesis develops an in-house system-level model of a hydraulic Cam Torque Actuated vane phaser in GT-SUITE. The model combines the hydraulic, mechanical, and electrical domains of the system, with particular focus on the Oil Control Valve and the internal oil flow paths governing phaser operation. The model is calibrated against test-cell measurements. The results show that the model captures the actuator and cam phasing behaviour observed in the measure ments, although some deviation remain. Beyond reproducing measurable system responses, the physics-based model enables investigation of internal quantities and oil flow behaviour that cannot be directly measured in the test setup. The de veloped model therefore provides a basis for improved understanding and further development of the cam phaser system.