Experimental Verification and Drivability Investigations of a Turbo Charged 2-Cylinder Motorcycle Engine 2014-32-0112

There are several reasons for equipping an internal combustion engine with a turbo-charger. The most important motivation for motorcycle use is to increase the power to weight ratio. Focusing on the special boundary conditions of motorcycles, like the wide engine speed range or the extraordinarily high demands on response behavior, automotive downsizing technologies cannot be transferred directly to this field of application. This led to the main question: Is it possible to design a turbo-charged motorcycle engine with satisfactory drivability and response behavior?

The layout of the charged motorcycle engine was derived by simulation and had to be verified by experimental investigations. Main components, like the turbo charger or the waste gate control as well as the influence of the increasing back pressure on the combustion, were verified by test bench measurements. Afterwards the operation strategy in general was investigated and applied to the prototype engine. The importance of the response behavior led to frequent transient measurements on the engine test bench to allow for changes. All these investigations were accompanied by a coupled 1D-CFD / MATLAB simulation so as to reduce the time effort for the boost control optimization. The test bench investigations were followed by on road measurements in order to analyze and improve the drivability of the prototype motorcycle.

The development work resulted in a prototype vehicle not only showing significantly higher low end torque than the basic motorcycle, but even displaying satisfactory drivability as well as extraordinary response behavior on a par with naturally aspirated engines.