Finding the Optimum Design of Large Gas Engines Prechambers Using CFD
  and Bayesian Optimization
Stefan Posch Clemens Gößnitzer Franz Rohrhofer Bernhard C. Geiger Andreas Wimmer
The turbulent jet ignition concept using prechambers is a promising solution
to achieve stable combustion at lean conditions in large gas engines, leading
to high efficiency at low emission levels. Due to the wide range of design and
operating parameters for large gas engine prechambers, the preferred method for
evaluating different designs is computational fluid dynamics (CFD), as testing
in test bed measurement campaigns is time-consuming and expensive. However, the
significant computational time required for detailed CFD simulations due to the
complexity of solving the underlying physics also limits its applicability. In
optimization settings similar to the present case, i.e., where the evaluation
of the objective function(s) is computationally costly, Bayesian optimization
has largely replaced classical design-of-experiment. Thus, the present study
deals with the computationally efficient Bayesian optimization of large gas
engine prechambers design using CFD simulation. Reynolds-averaged-Navier-Stokes
simulations are used to determine the target values as a function of the
selected prechamber design parameters. The results indicate that the chosen
strategy is effective to find a prechamber design that achieves the desired
target values.