This paper studies the problem of dynamic inflow below the rotor disk for skewed flow. With the information from the adjoint inflow equations plus the normal states, one can calculate the velocity in the hemisphere below the rotor disk plane without losing accuracy or convergence rate. The methodology enables one to calculate the velocity below the rotor disk with the finite-state method with the only cost of adding the uncoupled co-states. The three components of inflow are considered here and compared with the results from the convolution integrals. Numerical results in the frequency domain for simple harmonic motion show the effectiveness of the new method in three-dimensional inflow with big skew angle below the rotor disk.
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