Intake Swirl Prediction of D.I. Diesel Engine and Its Matching with Fuel Spray

Air motion in combustion chamber has significant effect on combustion process. However, the air flow in the cylinder of running engine cannot be measured easily. Prediction model of intake swirl is established based on the experimental results of steady flow rig, which connects the steady testing with the practical intake process. Under the conditions of guaranteeing charge performance of the sample engine, the original inlet port is modified. The intake swirl generated by the improved inlet port matches well with fuel spray through the computer simulation of the prediction model. Performance tests of engine show a little decrease in fuel consumption and exhaust temperature with improved inlet port.