Thermal analysis of an off-road machine with a conjoint 3-D CFD and 1-D network simulation package

To gain insight into the ventilation needs of an enclosed engine compartment of an off-road machine, we performed analyses to predict underhood ventilation air flow and component temperatures in the test rig. The analytical work involved development, validation, and application of these methods to optimise ventilation air flow rate. A 1-D thermal-fluid network model was developed to account for overall energy balance and to simulate ventilation and hydraulic system response. This model was con-jointed with a 3-D computational fluid dynamics (CFD) model for the ventilation air circulation to determine the flow patterns and the distributed surface heat transfer. The tests provide an opportunity to understand the isolated effect of ventilation air cooling on underhood thermal control.