A Modular Internal Combustion Engine Blow Rig and Cold-Flow Analysis Concept for Industrial Particle Image Velocimetry Measurements under Steady, Near-Reality Charge Air Conditions

A modular, stationary IC engine blow rig for differential and integral flow field measurements using particle image velocimetry (PIV) has been developed. Unlike conventional PIV blow rigs, the given design is capable of operating under near-reality charge air conditions, that is, highly pressurized, hot intake air supply at high flow rates. Its conceptual flexibility as well as peripheral infrastructure allow for comprehensive and wide-ranging flow field analysis. Because of a modular architecture, it is neither confined to a specific cylinder head design nor limited solely to the application of PIV for differential flow field analysis. It also already accounts for direct inlet flow determination through an additional PIV access point upstream of the cylinder head. The inlet and outlet ducts have been designed with regular shapes and smooth walls, such that a digital twin-type CFD model of the blow rig is conveniently feasible. A specifically developed pseudostereoscopic reconstruction method is applied to acquire fully 3D volumetric velocity fields from plain sequential 2D measurements using only a single PIV camera and laser sheet. The resulting volumetric flow field is used to, for instance, determine the locations of vortex cores, 3D streamlines as well as zonal swirl coefficients in the sense of a “virtual paddle wheel” measurement.