Numerical databases established by large-eddy simulations of subsonic turbulent boundary layers and separated shear layers are utilized to simulate Malley probe measurements and investigate their accuracy and consistency with the data obtained from two-dimensional (2-D) wavefront sensors. It is found that the Malley probe data give a good approximation for the boundary layer and a reasonable approximation for the separated shear layer in terms of the root mean square of optical path difference (OPD rms ) and the streamwise correlations of OPD. The OPD rms from the Malley probe is slightly smaller than that from the 2-D wavefront sensor with the same streamwise aperture size for both flows. It is shown that the use of multiple Malley probes in the transverse direction of the flow can enhance the accuracy of measurements. The spatial correlations of OPD obtained from simulated multi-Malley-probe data are also examined and compared to those from 2-D wavefront sensors.