Fig. 8

The plots in a–d show that a sensor rate \(\rho ^{\text {basis}}< 30~\%\) for the construction of the gappy POD basis is insufficient and that the rebuilt reduced model cannot be recovered with the adaptation from incomplete sensor samples in this example. Even increasing the sensor rate \(\rho ^{\text {update}}\) to \(\rho ^{\text {update}}= 90~\%\) cannot compensate the poor approximation quality of the obtained gappy POD basis. Increasing the sensor rate to \(\rho ^{\text {basis}}= 30~\%\) leads to a gappy POD basis that approximates the complete sensor samples sufficiently well so that the dynamic data-driven adaptation recovers the rebuilt reduced model, see e and f. The dimension of the gappy POD basis is set to \(r= 30\)