MATLAB® Modeling of an IC Engine as a Capstone Learning Experience in a Combustion Engines Course 2016-01-0173

There is insufficient time within a single technical elective to learn principles of internal combustion engine operation as well as specialized simulation tools such as GT Suite or Kiva. A number of authors have recognized this constraint, and they have structured their internal combustion engine text around use of programming languages such as FORTRAN, C++, and MATLAB®. This paper reports on how the capabilities of MATLAB® have been synergized with learning activities and homework assignments to set the stage for a successful final engine simulation project. The MATLAB® code involved in this effort can accept basic input parameters such as bore, stroke, compression ratio, spark advance, throttle position, RPM, air/fuel equivalence ratio, and volumetric efficiency. The code returns output power and torque using the Wiebe function and bulk temperature. The model uses a two-zone heat release model to predict power, torque, brake specific fuel consumption, and volumetric emissions. An engine-specific volumetric efficiency map is suggested to ensure accurate results at all throttle positions. Students are pleasantly surprised at how well their customized MATLAB® model is able to match published performance data from a diversity of applications: mopeds, racing motorcycles, sedans, and SUVs. Our most successful outcome to date has been the modeling of a Yamaha YZ250F engine that is used in our Formula Hybrid SAE competition vehicle. The simulation produced power and torque results very close to the actual outputs of the engine, and the predicted fuel map was validated in our small engine lab as well as in vehicle performance checks.