The main advantage of coupling to 1-dimensional codes at the time-step level is that there is a simultaneous interaction between the 1D and 3D solutions and this allows the complete system model with dynamic effects in the intake and exhaust systems, interactions between cylinders etc. to be accounted for accurately in the STAR-CD model.
Typical applications include: unsteady boundary conditionsfor intake calculations of 4-stroke engines; EGR mixing; scavenging of 2-stroke engines and other instances where combined detailed and system level models are needed to deliver the level of fidelity required.
Derivation of spatially-varying cycle-averaged heat transfer boundary conditions is a prerequisite for making accurate calculations of structural temperature. Here, the focus is not the fluctuation of surface temperature that occursduring the engine cycle but rather the steady-state or more slowly varying thermal transients that affect the entire structure.
Averaging of the instantaneous local heat-transfer coefficient and gas temperature determined by the STAR-CD solution is calculated as a post-processing operation and this can then be mapped to the structural model, thereby allowing for spatial variations within the cylinder, that occur during the entire engine cycle, to be represented correctly in the 3D solution of structural temperature.
CD-adapco has been actively involved with in-cylinder analysis from its inception and there are many engines in production around the world today that have benefitted from detailed analysis using the STAR-CD/es-ice suite of software. These range from the smallest motorcycle through car and truck engines to the largest stationary and marine engines.
To keep pace with developments in engine technology, CD-adapco is continually developing the software to add new capabilities, functionality and the speed and ease with which powertrain engineers can execute projects.