涡轮增压天然气发动机电控系统进气模型研究

Aiming at the problem of poor accuracy and portability of normal intake charge calibrating method used in natural gas engine and taking a Weicai WP10NG336 turbocharged single-point injection natural gas engine as the research object, an intake charge model suitable for natural gas engine was studied. Based on the mean model, the equivalent gas flow was used to describe the intake process. The gas flowing through the cylinders was divided into reversing flow exhaust gas, scavenging exhaust gas, backflow residual gas, consistently stayed residual gas and fresh equivalent gas. Synthetic modeling and analyses were conducted on the turbocharger, throttle valve, intake manifold, exhaust manifold and cylinders, and the model was verified in consideration of the influence of intake inertia. Experiments on the WP10NG336 turbocharged natural gas engine were conducted, and results showed that the error range of the intake model proposed in this paper is within 4% and the air charge model is able to accurately estimate the actual air charge under different working conditions while occupying little computing resources.