In contrast to that, qualitative load control takes full
advantage of the lean burn ability of hydrogen and avoids
the intake throttle losses [12]. The relative air–fuel ratio is
adjusted depending on engine load while the intake airflow
is unthrottled, similar to a diesel engine [13]. This can
either be done with using homogeneous (Fig. 3 center) or
inhomogeneousVBstratified[ (Fig. 3 right and Fig. 4)
mixture conditions. Both strategies show advantages due