b'Automotive | Engineer Innovationbe recirculated into the intake-portIntake Port Fuel during a back-flow phase right beforeMass Fraction (%)intake valve closure.While many of these effects are to beLiquid Fuel Residual qualitatively expected from first sight,Mass Fraction (%)the algorithm manages to find - otherwise hard to identify - optimum compromise solutions in this space of numerous competing objectives. Despite the strict requirements on valid Turbulent Kinetic solutions several feasible strategiesEnergy (J/kg)were found using the proposed method.A detailed analysis thanks to CFD allows for a deep insight into how the spray impacts the intake jet and fuel Equivalence Ratio distribution in dependence of the@ Spark Plug (-)respective injection timings. The bigInfeasibledata analysis reveals how outstandingFeasiblestrategies manage boosting the fuelBest Infeasibleuniformity and tumble with ideallyReferenceEquivalence Ratio timed early intake-phased pulses,Uniformity Index (-) Best Feasiblethereby improving the later turbulence level as the tumble breaks down, at the same time ensuring ignitability and a further boosting turbulence with aInfeasibleperfectly timed late pulse. All this while simultaneously mitigating Injection Rate (a.u.)fuel related constraint violations as much as possible.ReferenceBased on these insights from the automated design exploration the engineers were able to choose among aFeasibleseries of better performing strategies each of which offered unique benefits.Intake Valve LiftIn comparison with the four pulse- 350 400 450 500 550 600 650 700reference strategy, two furtherCrank Angle (degree)strategies stand out: a three pulseFigure 4: Performance metrics of all studied injection strategies (top) and selected interesting strategy, where the intake port fuel andcandidate strategies (bottom)liquid fuel present at spark timing are reduced by eighty percent and sixtythe engineers experience-based final percent respectively, at a slight cost ofassessment of better-rated options that reduced turbulent kinetic energy, andadds significant value to the engine another one consisting of two pulsesoptimization process.improving vaporized fuel present in the engine, levels of turbulent kineticWhile the study at hand has proven the energy and fuel homogeneity, allpotential of CFD-based rate shaping for simultaneously, at acceptable penalty ofgasoline direct injection engines, fuel back flow to the intake port.Siemens engineers only see it as a starting point. Thanks to a fully Which one might be the right choiceembedded automated workflow, remains an engineering challenge thatextensions to spray targeting, valve typically cannot be answered by anytiming, or piston shape optimization are algorithm. It is the synergy of efficientonly a few mouse-clicks away, offering a automated identification of high- toolset to not only shape future injection performing strategies in a highlyprofiles but the complete gasoline direct complex design space combined withinjection combustion system. n49'