Tank model for coffee filtering
\(\displaystyle {d H(t)\over dt} = - \alpha \, H(t) + P(t)\) with \(H(0)= H_0\)
\(H(t)\): water height
\(P\): inflow
\(Q(t) = \alpha \, H(t)\): outflow
Introduction to Data Assimilation for Scientists and Engineers
\(\displaystyle {d H(t)\over dt} = - \alpha \, H(t) + P(t)\) with \(H(0)= H_0\)
\(H(t)\): water height
\(P\): inflow
\(Q(t) = \alpha \, H(t)\): outflow