Development Process to Optimize Design and Performance of Small Gasoline Engines

Abstract

<div class="section abstract"><div class="htmlview paragraph">The further optimization of modern gasoline engines needs sophisticated development tools to meet future emission legislation and fuel consumption targets. The multi-dimensional optimization process has to take into account parameters like</div><div class="htmlview paragraph"> <ul class="list disc"> <li class="list-item"> <div class="htmlview paragraph">Cylinder head and port flow design</div> </li> <li class="list-item"> <div class="htmlview paragraph">Valve train variabilities (e.g. camphasers, variable valve lift systems)</div> </li> <li class="list-item"> <div class="htmlview paragraph">In-cylinder charge motion and interaction with mixture preparation</div> </li> <li class="list-item"> <div class="htmlview paragraph">Resulting combustion characteristics</div> </li> <li class="list-item"> <div class="htmlview paragraph">Naturally aspirated and boosted operating conditions</div> </li> </ul> </div><div class="htmlview paragraph">The paper presents an advanced development process, where a dedicated interaction between</div><div class="htmlview paragraph"> <ul class="list disc"> <li class="list-item"> <div class="htmlview paragraph">Gas dynamics and CFD simulation,</div> </li> <li class="list-item"> <div class="htmlview paragraph">Optical analysis tools (3D-PIV) and</div> </li> <li class="list-item"> <div class="htmlview paragraph">Engine test bench</div> </li> </ul> </div><div class="htmlview paragraph">is used.</div><div class="htmlview paragraph">Simulation approaches are typically used during the first concept and following design phase. Due to the complexity of simulation models and the need for a detailed validation, advanced optical analysis tools need to be integrated in the development process. Among others a 3D-PIV test bench is set-up to analyze the flow pattern inside the cylinder especially during the intake phase in all relevant details. The validated model is then used to improve quality of combustion simulation and a higher accuracy of process prediction is realized. The simulation prediction is finally checked by engine test bench investigations.</div><div class="htmlview paragraph">The methodology is exemplary shown for small displacement engine versions. Finally, a detailed assessment can be realized, which takes into account all relevant development targets.</div></div>