Treatments of Geometry Source Terms in Ce-se Method to Improve the Mass Conservation Property in Tapered Ducts of Internal Combustion Engines

In one dimensional codes, a cross section area variation versus the duct length can produce important mass conservation errors when the gas-dynamic through the ducts of an internal combustion engine (ICE) is modelled. The CE-SE scheme (Conservation Element-Solution Element) is a numerical method that combines accuracy and speed in constant section ducts, but it presents a lack in mass conservation when a conical duct is solved. Recently, a new version of this scheme has been developed . This new approach solves the source term with a semi-implicit process. It offers good results but does not achieve the accuracy offered by other high resolution schemes. The purpose of this work is to present new technics to evaluate the source term corresponding to the cross section area variation in the CE-SE scheme and to improve the mass conservation through the duct.